The largest offshore wind farm is nearly complete, can power 1M homes | Hacker News Reader

The largest offshore wind farm is nearly complete, can power 1M homes

edition.cnn.com

143 pointsneverminder156 comments

My local constituency was going to achieve this honour but unfortunately the local MP Robert Syms (known to be somewhat corrupt) killed the project on utterly bullshit grounds (it would barely have affected the view): https://en.wikipedia.org/wiki/Navitus_Bay_wind_farm

As a contrast, it was also reported today that Hinkley point will be £2.9 billion over budget: https://www.bbc.com/news/business-49823305 luckily for them, they get to charge £92.50 per megawatt hour upon completion - locked in for 10 years. While wind power is costing us £40 per megawatt hour, not guaranteed, and likely to decrease.

The "World Nuclear Industry Status Report 2019" says that:

> even the extended operation of existing reactors is not climate effective as operating costs exceed the costs of competing energy efficiency and new renewable energy options and therefore durably block their implementation. Mycle Schneider concludes: “You can spend a dollar, a euro, a forint or a ruble only once: the climate emergency requires that investment decisions must favor the cheapest and fastest response strategies. The nuclear power option has consistently turned out the most expensive and the slowest.”

https://www.worldnuclearreport.org/WNISR2019-Assesses-Climat...

>The World Nuclear Industry Status Report is a yearly report that explores the global challenges facing the nuclear power industry. It is produced by Mycle Schneider, a professional anti-nuclear activist, and gives a detailed overview of the global nuclear industry and special analysis on key events and trends.

https://en.wikipedia.org/wiki/World_Nuclear_Industry_Status_...

Hardly an unbiased source it seems.

Regardless, the issues facing nuclear power could be quite easily solved with simple political will. Unlike those of renewable energy, which still do not have economical or technologically feasible solutions to the storage and base load problem.

We need only look to France to see the path forward. After the 1973 oil crisis, they resolved never again to be beholden to foreign oil for their grid needs. So they undertook the Messmer Plan, which mass produced a single standardized reactor design in bulk. France converted itself almost entirely over to nuclear power for its base load requirements in just 15 years, with the project coming in under budget and ahead of schedule. Now France has so much electricity it sells excess to Germany for profit.

Taking advantage of economy of scale, slicing through red tape and NIMBY-ism with political willpower, using a standardized design to expedite the engineering and approval processes of every individual plant - none of these require some amazing new technology or some new economic system be developed. We could literally start tomorrow, and have the entire first world swapped over to nuclear by the 2030s.

The recent Netflix documentary "Inside Bill's Brain" has an episode on Gates' attempts to build a safe nuclear reactor. It's been blocked by political opposition, not anything technical.

> We need only look to France to see the path forward.

I hope nobody does that. France is running several overdue reactors, has a history of under-reporting issues, the main electricity generation and distribution company EDF (owned by the state) runs with a net debt of €70 billion and is responsible for the disastrous over budget numbers for Hinkley OP mentioned above.

> Now France has so much electricity it sells excess to Germany for profit.

Germany sells excess electricity also...It's a flowing market depending on daily prices. The overall price development however showed that it rose in France while it fell in Germany: https://ec.europa.eu/eurostat/statistics-explained/images/4/...

With the continued rise of renewable energy in Germany this development won't stop while France will at some point have to start moving some of their overdue reactors off the grid while new ones are being dropped because of the market situation outlined in the Status Report above: https://www.reuters.com/article/us-france-nuclearpower-astri... while the only other new reactor they build Flamanville 3 came up in the news with messed up welding seams...

"slicing through red tape and NIMBY-ism with political willpower"

Red tape is there for a reason. Red tape is the rule of law, it's emissions standards, and fines for polluters, employment rights, and safe drinking water.

Red tape isn't something to be cast aside to get your own personal pet thing done.

I mean, what's the difference between your 'political willpower' and dictatorship?

The French approach gets them TGV, Ariane, nuclear power. Surrounding nations rush to add high speed rail after TGV.

Meanwhile... The British approach makes it illegal to give government funding for the Channel Tunnel rail link. 12 or 15 years later, another Act is needed and we start bothering with HS1. HS2 and HS3 were allegedly "coming soon" while the Chunnel was being built. Hmm.

Ariane is European. According to Wikipedia "it was officially agreed upon at the end of 1973 after discussions between France, Germany and the UK" [1]

Plus the British approach has just built the biggest offshore wind farm. Why is that inferior to Frances nuclear power?

Plus France also signed up to the Channel Tunnel treaties, so its also illegal for them to fund it, but yet it still got built...

And which approach gets to claim credit for Concorde?

I'm not even sure what the French approach is. They still have to follow EU red tape, I could just as easily roll out a stereotype about long lunches, etc, etc.

[1] https://en.m.wikipedia.org/wiki/Ariane_(rocket_family)

To add to this:

> The TGV was the world's fourth commercial and third standard gauge high-speed train service,[15] after Japan's Shinkansen, which connected Tokyo and Osaka from 1 October 1964, the Russian ER200 around 1974 (full service in 1984), and Britain's InterCity 125 on main lines such as the East Coast Main Line, which entered service in 1976.

https://en.wikipedia.org/wiki/TGV#Milestones

The post-war British approach, late 60s, early 70s on has been much more piecemeal eschewing big national projects we used to do well. The French retained the ability to use the state for good much longer than us. Or push vanity projects through, come what may, if you prefer... We did joined up thinking much better until the 1950s.

The French were the driving force behind Ariane. Britain would most likely have walked away after the failure of Europa (Blue Streak). We did after all walk away from our space programme right after achieving orbit. Still we became a much smaller participant in ESA than we had been in ELDO. Germany took our place as the other key player with the French.

The point about the Tunnel was the British Tunnel Act specifically ruled out state aid - Thatcher's government expected the private sector to stump up the whole cost. Which it pointedly failed to do. France happily took the SNCF proposal and built a national network from it using the power and purse of the state. Britain took the BR APT prototype, pushed for far too early demo, cancelled it, sold it to Fiat then bought them later as Pendelinos. We chugged along with HST.

Concorde is a brilliant pick, thanks for the perfect example! I'm going to say 95% "The French" (politically. We contributed much more fairly technically): The British really, really wanted to partner with the US who weren't interested feeling they would be giving "their" lead to the UK. We were most surprised to find the French were the most serious about SST too, and Thorneycroft (destroyer of Supersonic Harrier) found himself with only France as realistic option. The treaty was written with very heavy cancellation penalties. Roy Jenkins tried to cancel it with TSR2 in 64. He went to France to tell them. The French responded by breaking diplomatic contact[1]. :)

Actually, scrub that, it wouldn't have progressed nearly as far as British project. Treasury were against, cabinet was against, but, we were trying our first attempt to get in the EU and de Gaulle wasn't keen (he felt we were too close to the Americans to be good Europeans. 2019 hindsight thinks he may have had a damn good point). Concorde was an EU/EEC bargaining chip. Yet still we tried to cancel it.

[1] https://history.blog.gov.uk/2019/04/09/concordes-first-briti...

Offshore wind also has guaranteed strike prices, although as you say much cheaper than HPC. One of the reason HPC strike price is so high is to pay for the guarantee that budget over-runs like this will not have a bill impact. If EDF goes belly-up trying to build it, that's no skin off our noses as bill payers.

The guarantee is only for 15 years as well, whereas it’s 35 years for nuclear.

Contractors look at funded reserves like lions look at red meat.

"known to be somewhat corrupt"

Based on the expenses scandal??

Local property developments. The expenses scandal was a good litmus test of who in parliament was honest and who wasn't though.

I asked because I googled, and the only thing I could see is a wikipedia reference to the expenses scandal. I've just searched again and cant find anything, so have you got any references?

Affected the view of a world heritage site it seems, to be specific. I looked into it expecting it to be a bullshit reason, but apparently 22 million people visit annually. Perhaps it's a valid reason after all.

22 million people do indeed visit Jurassic coast but the wind farm would have been invisible from there. Note the weasel wording in the wikipedia article.

It was far enough that it would have been faintly visible from Bournemouth beach. I strongly doubt that a few dots on the horizon would have bothered any tourists.

This project wasn't killed because of the view. There were other financial (probably carbon based) interests involved.

I'm no expert on the area however, it's not wilderness area, this is the channel coast, the navy has a firing range next to Lulworth Cove and there is a stack of rusting wrecks just off the coastal path... people just don't like the aesthetics for less than rational reasons but each to their own.

It's also adjacent to one of the world's busiest shipping lanes, and several of the UK's busiest ports. I visit the area often, and while the area is beautiful, the horizon is always full of ships. Some wind turbines will make no difference.

Wind farm protests about aesthetics mystify me.

Driving through central Kansas, the towers are just this stark reminder of how far we've come, and how little we are. You see nothing, nothing, nothing... then BAM! These massive towers generating energy from the winds on the plains, in a state named for the people of the south wind. All of them impossibly tall, the field going on for miles, your mind doesn't even really process how big an individual one is, let alone the scale of the whole farm.

They always hit me like a monument. Like that feeling you might get walking into a cathedral with a slow whistle up at the ceiling. It's more than that, though, it's bundled up with a bit of futurism from the new tech, a bit like finishing a piece of utopian sci fi at the same time.

There's no accounting for taste, for sure. So maybe some people are just accustomed to the way certain views used to look and don't want any change. Maybe they grew up there and have strong attachments.

It's just hard hearing people dismissing beauty as blight, something that could be sublime if they just looked at it a slightly different way.

We see them dotted across the hills when driving through parts of Northern California - they're beautiful!

I think they also give a beautiful perspective to size and distance in Wyoming and Eastern Montana.

Well said.

I worked in wind energy visualisation and attended many community presentations - I've been up-close to these protests. It's not just about aesthetics, concerns range from fear of lowered real-estate value, low frequency health scares, wildlife concerns, shadow flicker and so on. Like you, I think they are beautiful - however at least here in Holland, that is generally not the case. I've seen a Vestas V164 in the flesh at a testing facility in Denmark and it was quite possibly the most incredibly man made object I've ever seen. With a 164 meter rotor diameter, your eyes almost can't work out how to focus on the blades - especially if you're standing directly under it. One moment the blade tip is close to you, and moments later it's 160 meters away. Amazing stuff.

Sounds incredible! When I worked for Vandebron we had a visit to a farmer in North Holland who had 2 wind turbines. They weren't the newer models so not the biggest, but I indeed remember the crazy feeling of perspective changing too fast when you looked up at the blades turning from directly underneath. It was a windy day, too....

I wish I'd been able to go up to the top. Must be amazing!

Beauty is one of the most subjective concepts a human can reason about. Who are you to tell anyone what is beautiful? Just because a bunch of techies here on HN find beauty in the engineering of a windmill, it doesn't mean everyone has to like them.

I don't dislike the design of wind farms, but sure as hell I'd prefer landscape unspoiled by a forest of big white rotating blades. Given the choice, I'd prefer a concentrated energy generator (whatever that might be), that can be hidden away. So in some sense, I do believe they are a blight on the landscape.

I'm super pro-renewables. The fact is that northern Europe is going to need nuclear to completely decarbonize (which is what is required to meet our goals).

Because of the long winters, to do the same with wind/solar will require about 3-5 times as much cost as you might think at first. You need to provide extra capacity to artificially increase effective capacity factor, and then you need about 48 hours of storage. Also possible, but about the same price, is hydrogen for seasonal storage for winter.

...and generally speaking, effectively any carbonfree project being built now needs to be supported. We need everything. Including a lot more off-shore wind.

> and then you need about 48 hours of storage

I think it's even longer than that, unfortunately... of course, it depends how much over capacity you have, but those cold fronts in N Europe can kill wind speed for weeks on end sometimes IIRC. It is a huge problem for us to solve.

If everyone has an electric car then, in principle, that battery can be used to keep your house alive for quite a long time. And of course once the battery capacity has declined so that you are no longer satisfied with the car's range you can repurpose the battery for home use to store the output of solar panels on your roof.

It's a huge problem in terms of time and finance but not a difficult technological one.

That's great, but large portions of the population live in apartments in those areas of Europe.

I hope very few people will own electric cars in the future (or any car whatsoever). We don't need more cars on the road - we barely can squeeze them on our roads now. We need good, fast, ubiquitous public transport system.

I don't think the need for nuclear is much of a fact. It's more wishful thinking. Norway gets by without it and uses wind and hydro (mostly) for most of their electricity needs. They have no need for nuclear whatsoever and they export energy. Iceland is famous for using geothermal. Scotland exports wind power and generates more power than they need that way. Also, places like Denmark, the Netherlands, and Sweden are relying on lots of wind (on and offshore).

The energy markets in Europe are connected and the fastest growing source of energy is basically wind. Coal is shrinking at this point and the enthusiasm for building new gas plants is likewise melting away rapidly as their cost seems to be on the high side compared to clean energy solutions. It will take decades to get rid of both of course.

Sweden and Finland actually both have nuclear plants. Finland even built a new one recently. But in general, nuclear is on the way out in Europe as there is no political will to commit to building new plants across the continent. Older plants are shutting down one by one. France has a lot of aging nuclear plants and they don't seem to be building new ones and are actively considering shutting a few down (https://www.france24.com/en/20170710-france-hulot-could-clos...). Apparently keeping their existing capacity online would take tens/hundreds of billions and the political appetite for those investments is pretty low.

Many EU countries are on a path to completely clean energy and it does not seem to involve building new nuclear plants.

I think increased interconnects are the way to go, but don't mind adding nuclear capacity. It's worth noting though, that Norway is quite an exception in their hydro capacity, as there is so much height differences in their terrain. Increasing hydro capacity is also pretty hard these days due to enormous environmental cost and the fact that most of the viable sites are already built.

> "I think increased interconnects are the way to go..."

What do you mean by this?

Power sharing across national borders was how I interpreted it. Common in Europe.

Yes. So there's smaller difference in wind power generation total output when you sum across larger area. The same is true for solar generation to some extent, but of course it's dark in the night across the whole Europe.

> Finland even built a new one recently.

They are still in the process of building it, and it is set to become the second most expensive building built in modern times. [0]

[0] https://metropolitan.fi/entry/olkiluoto-ol3-second-most-expe...

So, do you care about the environment or not?

It should be reduce carbon no matter the dollar cost, right?

It's utterly delusional to think that low density generation such as solar or wind can meet the growing energy needs without covering vast areas.

And electric vehicles will just increase the need.

> It should be reduce carbon no matter the dollar cost, right?

The point is that nuclear is expensive. You get more energy per dollar by building renewables.

That's only true at low penetration of renewables. When you approach 100% clean energy, even current new nuclear actually looks just as cheap or cheaper as the combination of curtailment (i.e. over-building nameplate capacity and throwing away much of the energy), storage, and transmission you need to produce reliable power with wind and solar alone.

(and for the same reason, we should be looking at expanding hydro and geothermal)

So while I definitely think we should build solar and wind, it's ridiculous to just dismiss nuclear out of hand for cost reasons if the goal is 100% clean energy (unless you have, say, massive amounts of hydro power).

Given the climate emergency, it's silly to pit one clean energy project against another when in fact we need all we can get. Particularly in the case of variable renewables, as they benefit tremendously from being in a source-diverse power grid.

And then there are countries like Estonia, Latvia, Lithuania, where hydro will never be enough, solar and wind will require ridiculous levels of storage and even nuclear is difficult to justify.

It's important not just to look at current electricity usage but total energy needs. To truly decarbonise you need to stop burning gas for heating, stop burning fuel for transportation (or convert to Hydrogen) and so on. So the existence of countries that can supply their current electricity needs via renewables doesn't immediately imply that for a zero carbon future renewables is all that is needed.

David MacKay covers this in his excellent book: https://www.withouthotair.com/c18/page_103.shtml

As for political will I feel we should first start with the numbers and works out what adds up. If people don't want nuclear but nuclear is the only path to zero carbon then we'll need to choose one or the other.

Right now we can make great progress by ignoring nuclear because there's lots of things to be done. So go all in on renewables and ditch nuclear is a politically easy choice. Does great things for the stats and many people don't like nuclear. Will it take us all the way though?

>As for political will I feel we should first start with the numbers and works out what adds up. If people don't want nuclear but nuclear is the only path to zero carbon then we'll need to choose one or the other.

I've not seen any figures which don't add up except ones which make some rather outrageous assumptions (e.g. no demand side management, no overproduction, intermittency stats based upon smaller, shittier turbines, etc.).

David Mackay's book is good but it's rather outdated - the figures are from 2006/2007 and renewables have plummeted so far in price since then that it rather changes the picture of what's achievable.

>So go all in on renewables and ditch nuclear is a politically easy choice.

I don't believe that's necessarily true. The nuclear lobby has spent a lot of money trying to make their choice politically easier.

The nascent renewables lobby, by contrast, doesnt' spend nearly as much on lobbying.

Renewables are happening very quickly and have put several countries on a path to a zero carbon energy economy. Some of these countries are ahead of their own schedules. Most of these plans are based on current efficiencies and costs for renewables and do not take into account improvements that are coming. That makes these plans overly conservative.

IMHO clean energy will take us a lot further than just our current base line needs because of these improvements. For example, right now people are reluctant to install air conditioning because of the cost of energy and concerns about global warming. Cheap, plentiful, clean energy changes that. If house owners can generate all the energy they need for a one time cost of installing batteries and solar, this concern goes away.

Hydrogen will be popular for things like heavy industry, shipping and other places where delivering large amounts of electricity cheaply is needed and batteries won't be good enough. These use cases are far fewer than most hydrogen fans hope/expect and IMHO excludes most forms of four wheel traffic on the road I don't see a business case for installing massive solar infrastructure when EV ranges are hitting 400+ miles already with rapidly improving recharge rates.

Most of that hydrogen will be generated using excess wind or solar and the business case for that will be that that energy is so cheap that the relative inefficiencies don't matter. It will have to compete with other synthetic fuels because at that point fossil fuels will be no longer be cost competitive with that either. Why buy barrels of oil at 50-100$ each when you can just convert kwh + water + air into carbohydrates?

Nuclear is on a slow but steady way out. At this point there are only a handful of countries investing in nuclear and quite a few have non technical reasons for this (i.e. military ones). R&d progress has been glacial and cost is an order of magnitudes from being competitive in the current market already. In most places that still have nuclear, it's one of the most expensive options in the market and there are a lot of nuclear plants at risk of shutting down early because of it.

IMHO fusion might still happen in half a century or so. By then most countries will have shut down all remaining coal, gas, and nuclear plants. At that point it will have to be super cheap to be off interest.

Being a net exporter of electricity does not imply that a country does not need nuclear.

Yes, some tiny European countries can rely on hydro or geothermal for baseline generation. Most countries can’t, and even if they’re a net exporter, they’re heavily dependent on fossil fuels (or nuclear) for filling in gaps.

Battery technology is nowhere near sufficient for the need, things like pumped storage are space intensive, and exotic stuff like hydrogen and molten sodium and whatnot are decades off. Something has to fill the gap. Nuclear is a good choice.

Nuclear is not a good choice because it would take decades to even agree that they need to be build and then decades more to actually build them. That makes it a pretty horrible option to fill any gaps. We can fix most of the issues you mention during that timespan. Honestly, it just requires applying economies of scale to what we have right now to drop the cost and make it even more cheaper than it already is.

I expect more nuclear to be shut down than being delivered during that time. It's not a growth market.

20-30 years from now, several countries are planning to be 100% on renewables and most of those are not planning to build any new nuclear plants. Most of the remaining countries will be making similar plans in the next ten years.

And there's mysteriously still no wind farm offshore that might ruin the Kennedy beach house view.

https://en.wikipedia.org/wiki/Cape_Wind

Would have been ~500MW as originally envisioned so still not this big =)

Edit: Missed the 137x in the wikipedia article so had the wrong power rating.

> Just a single rotation of one of the turbines can power the average home for an entire day

That is incredible!

By my power-wasting standards, I use about 8 KWh a day. A max 7 MW(h?) turbine generates at most 1.94 KWh of electricity a second. It seems to take 3-4 seconds for a single turn. The math checks out and this is, as you say, incredible.

This math checks out but the way you present the units is deeply confusing. It's not your fault though, I blame watt-hours.

You use 8kwh==28.8MJ of energy per day. 28.8MJ/7MW turbine is about 4 seconds, as a watt is a joule per second.

I found his units to be significantly more clarifying than yours. There's nothing wrong with having units of time (or distance) in both the numerator and the denominator, depending on the context. For instance, the Hubble constant is commonly expressed in km/s/Mpc, and astronomers purposefully don't cancel the units of distance.

In this case, there are two distinct timescales involved: the scale on which the energy is used (an hour or day) and on which it's generated (a second). It's ok to keep track of those separately.

There's nothing "wrong" with the units, besides that it is easy to get confused, evidenced by GP calling the turbine "7MW(h?)".

If you want to compare, however, you will have to convert to common units, and I at least find it easier to use watts and joules than watt-hours/second and watt-hours. By all means convert to stationary-bike-hours and big macs or whatever unit at the end but calculations are easier in the SI units.

Hubble's constant is expressed like that because it is a nice unit for the math.

> In this case, there are two distinct timescales involved

Three really: seconds, hours and days.

8 kWh per day = 8 Joules per second ⋅ hours per day ~= 330 Watts

Sometimes you even get four time units in one go. e.g. "I averaged 8 kWh per day last year"

It's madness.

My home uses 72 kWh/day (16-20 of that is charging a Chevy Volt), so even at my extreme usage, it's less than two minutes to provide my daily power needs. These are amazing:

https://www.siemensgamesa.com/en-int/products-and-services/o...

Why are you using so much power? Do you use electric for everything including heat and cooking?

Over 4000 sq feet, three stories, mid-atlantic. I need to have an energy audit done though; it's still a lot.

Yeah, that seems entirely crazy to me.

I was like "That seems high" so I checked my usage meter and it say 112kWh. OK then. Then I notice it's set to monthly.

So that's about 4kWh per day. It will be a bunch more in winter, and your place is much bigger than mine, but still - that number seems kinda crazy huge to me.

That is awful.

That’s a _lot_. That would cost you 5k euro a year here! Do you have a good sense where it’s going? Unless there’s something obvious, you might want to get the meter checked.

It's the kind of figure that suggests someone has tapped the supply and has a cannabis farm next door.

8-9 tons of A/C split across three units. High ceilings. All windows, some of them quite large, are on the east and west side of the house. They are double-paned, but still. We have shutters but they are mostly open because we like the light. I work from home, and we home school our kids, so the house is always occupied.

We don't keep the house exceptionally cool. 78° during the day, 74° on the second floor at night just before bed.

I really need to try and track things down a bit better. I've got two sub-panels and it's a lot of circuits to track it down. I can start by monitoring the obvious things though: A/C units, refrigerators, dryer. I recently replaced two of the A/C units, but around the same time switch from natural gas dryer to electric and that seems to have been a wash.

Power comes from a nuclear plant less than 10 miles away, so at least it's clean? :-(

If I've done my math right on the A/C units, they pull a combined 8500 watts. It would only take them each running on average 15 minutes per hour to eat up 52 kWh per day.

Two 14 SEER units, one 3.5 ton, one 3 ton, and a 10 SEER 2 ton unit.

1 ton = 12,000 BTU.

(6.5 x 12000) / 14 + 2 x 12000 / 10 = 7971 watts.

The air handlers have 1/5 HP motors, call that another 150 watts per air handler, so we're up to 8500 watts at least.

52 kWh / 8.5 kW is a little over 6 hours, or 1/4 of the day.

To use less power and still have a comfortable home, I'd have to insulate it better and switch to smaller and more efficient A/C units. The units are sized properly according to:

https://asm-air.com/airconditioning/what-size-central-air-co...

That's....huge.

For reference, I use 30kWh/day but I live in an 80 year old all-electric house (heating, water, cooking, ...) where temperatures go down to -30 degrees celsius and winters last for 6 months. Plus both my wife and I work from home so the heating and lights etc. are on all the time. And I still think it's way too much !

For comparison, that's a bit more than the electric consumption of all fourteen 90 years old houses on our street combined. Would cost roughly 650 USD a month over here.

Unless you are running an extremely energy intensive commercial operation at home, there's a lot of low hanging fruit to be picked. Get an energy audit yesterday. That could hugely benefit all of your comfort, your wallet and the environment.

8 KWh/day is very impressive. How did you get it that low?

I guess it's all relative! I'm not home much of the day, live in a newish condo with LED lights, and heat and cooking use natural gas. 8 KWh feels like a lot to me as it's enough electricity to power an oven for several hours each day.

The common advice (in Denmark) is to buy energy efficient electrical appliances. Fridges, washing machines, dishwashers, and led lights are labelled[1] so consumers can decide for themselves.

School kids are taught (well, at least I was) small habits such as boiling just the amount of water that you need, cooking with the lid on, turning off the oven 5 minutes before the meal is done, etc.

These energy saving habits are motivated by taxes on energy consumption.

The average household in Denmark use 4.4kWh/day per person (1600kWh a year) and the current recommendation is to be aiming at 1000kWh/year[2].

[1] https://en.wikipedia.org/wiki/European_Union_energy_label

[2] https://sparenergi.dk/forbruger/el/dit-elforbrug (in Danish)

Is it low? My last bill said I averaged 5kwh/day last month, my February bill averaged 7kwh/day. That's gas heating and hot water though.

I have a smart meter in my apartment.

A few weeks ago I was on holiday. Usage was 2.5kWh per day, about 100W, which is the fridge and a low power PC (NUC).

Otherwise, it's 3-6kWh per day, and depends whether I did laundry and cooked or not.

District heating and water.

Mine is 7kW a day; smallish house, LED lighting, gas heat and stove (though electric oven). I believe a good bit of that is the drier, tho.

Have you looked into heat pump-powered dryers? They cost a little more up front, but seem to be much more energy-efficient.

Due to space/kitchen layout constraints, I've got an integrated combo washer-dryer; I don't think anyone currently makes a heat pump one.

Something many people are not aware of is that the UK is a lucky country in terms of natural resources, with these resources playing a critical role in the development of the country over thousands of years. Wind power is just the latest example, and there's still plenty of resources left underground for the future, should the economics turn positive.

Somewhat ironically, one factor that has greatly facilitated the development of offshore wind in the UK is the world leading expertise in offshore construction gained through decades of exploitation of North Sea oil and gas.

Wind particularly. There are nine licences agreed for farms as large or larger than Hornsea One, including Hornsea 2 and 3. Another licence round due in a couple of years, and a lot of coastline to go...

Yep! I remember being amazed at how long Scotland's Cruachan hydro plant has been in operation.

It certainly helps that the North Sea is very shallow. Lots of it is only 25 or 30 metres deep.

Wow, a seven-megawatt wind turbine is ~9300 max horsepower.

Looks like the capacity factor is around 38% so the turbines are making ~3500hp avg.

http://energynumbers.info/uk-offshore-wind-capacity-factors

This commentary is a bit humorous. Is there some purpose for which the alternative to using a wind turbine is using a herd of 3500 horses?

"Horsepower" as a unit made sense when it was being used to market steam engines as an alternative to horses, because it made the tradeoffs obvious: it's clearly cheaper and easier to maintain steam engine than the 20 horses needed to do the same work. It might still be relevant for something like tractors where horses would be a reasonable alternative, but something like "carbon tons" (the tons of carbon produced by fossil fuel production of the same electricity) might be a more useful comparison for wind power.

horsepower was always just marketing bunk, with no actual work equivalence

It was a decent approximation of a the level of continuous work output you could expect out of a horse without taxing it too much.

A 3500hp diesel engine will burn around 197gal (745L) of fuel per hour.

One gallon of diesel when burned makes around 10.336kg of co2. So each turbine is preventing around 2 tons per hour of co2 emissions. Could be as much as 5 tons if it is replacing coal.

Apologies for use of freedom units; habits are hard to break.

https://barringtondieselclub.co.za/technical/fuel/diesel-fue...

Capacity factors for new, 7MW offshore in the UK is north of 55%.

"On the other hand for offshore wind farms in Denmark the normalised load factor falls from 39% at age 0 to 15% at age 10."

https://www.ref.org.uk/attachments/article/280/ref.hughes.19...

The title should say has the capacity to power 1M homes. No wind farm ever generates to capacity. And they age very quickly.

This tech maybe better and last longer than in the quoted, but it will still degrade over time. So in 10 years maybe it will be 20%?

Wind is not reliable – so where does the power come from when the wind is not blowing? If you say batteries, then you need excess generation (a lot) and a lot of batteries.

Wait, they lose 60% of their energy production potential within 10 years?

This number seems unbelievable.

Are the rotors falling off the towers and not getting replaced?

Are you sure that number is correct ?

I suspect that these numbers simply reflect the fact that

recent installations have higher capacity factors than installations 10 years ago.

These numbers seem to show the progress in wind power technology over the past 10 years and not a degradation of existing installs

"There are two plausible explanations for the observed decline in average load factors as wind farms age. The first is that the turbines become less efficient over time as a result of mechanical wear and tear, erosion of the turbine blades and related factors. The second is that the turbines experience more frequent breakdowns and their operators take more time to bring them back into service because they are less concerned about the performance of older plants. Both reasons may be relevant in different circumstances and it is not possible to identify a primary explanation from the data. "

> Where does the power come from when the wind is not blowing?

* Gas peakers

* More interconnects, particularly to places with pumped hydro resources

* Batteries (yes, it needs a heck of a lot. But battery tech & economics are still improving)

* Solar PV (we can build interconnects to the larger installations being built closer to the equator in places like N Africa)

Also worth noting the citation you posted is from 2012. Wind turbines have changed significantly just in the last 5 years. I wonder what the numbers look like today, in particular load factor decay?

Last year Denmarks weather was amazing, which meant no wind at all. What was the solution? Coal from germany who despite having great weather too and based on sun couldnt do anything else. This is the reality. The two countries with the supposedly most agressive use of alternatives cant even support each other without the use of coal.

Goes to show the climate change we're facing can only be properly countered while (mostly) maintaining nowadays' lifestyle if we, as societies, take caring of being less "every man for himself" and work more toward a solidarity-based world-view. Basically, we need to stop pretending and start acting the Human Rigths we created about 70 years ago. Individualism has failed, animosity culture has too. A simple solution would be to have the global power grid more connected: when it's winter on the north, it's summer on the south, so the winter countries could easily get energy from say, Sahara's Desert's solar plants. It's just an example.

An interconnected sustainable grid would foster the necessity of developed countries properly paying back to the atrocities committed to to underdeveloped countries, with things such as:

1) Investing in development, education in such countries

2) Investing in sustainable energy generation there

3) Subsidizing the costs of much 1st world technology in order for those countries to rise out of extreme poverty

Again, just simple examples; used African continent but could be extended to many other places. We need a "Green New Deal" because extreme capitalism has failed to a point we're now facing our own extinction if things continue like they are. Sure, sounds like wishful thinking, or something that would require some kind of ultimate class-based warfare, but I do believe this path can be achieve without a bloodstained revolution. The alternative is to be enslaved by the plutocracy and eventually to die off as a species, in the far future. Or bear arms and get your hards dirty, but I'm not an advocate for that.

What Greta has said in the UN, I agree with her: the current way dominant classes are acting upon the world's most damning issue seems to be a simple act of looking with a blasé face and not caring. If the wealthy believes all those billions are just going to watch as life becomes utterly difficulty on this planet, they may find not everyone is as peaceful as I am.

In short, there's no sustainable future with the way capitalism operates currently.

We are already doing the things you want us to do.

The only way to solve this is through capitalism not through the currently politically motivated energy capitalism where they pick the winners.

Capitalism certainly ain't perfect but it beats all other structures hands down. It does so because it recognizes human nature which is part selfishness and part altruism and existing in a gradient depending on the relationship of the partners it's in.

Keep in mind that most of our success as rich nations is because of our use of energy especially fossil fuels.

There is no current sustainable energy generation that can solve the increasing need for energy without the use of more fossil fuel and there is no curren green energy supply that can deliver as stable as Nuclear.

The chances of Greta being alive today without the use of fossil fuel and our energy consumption would be much lover. We don't owe anything especially not to a little girl who is being misused by cynical politicians and environmental organizations to make unscientific claims and to blame the very generations that have made sure she is able to grow up in the most safe environment of all times.

Capitalism is the only way we can move forward, the idea that a few politicians know what to is exactly the kind of dangerous thinking that is leading us towards a less safe, less prosperous world.

> a little girl who is being misused by cynical politicians and environmental organizations to make unscientific claims

Ridiculous right wing smears. Is this what the pro-nuclear lobby has sunk to?

As far as i am concerned she is the one smearing and the organization around her largely guilty of that. And talk about smearing. And I'm not right wing. So pot calling the kettle

False. At least provide some kind of citation for such an exceptional claim.

Source: https://windeurope.org/wp-content/uploads/files/about-wind/s...

1.5 WIND POWER GENERATION

Denmark had the highest share (Percentage of the average annual electricity demand covered by wind) (41%) in Europe in 2018.

The figures represent the average of the share of wind in final electricity demand, captured hourly from ENTSO-E and corrected thanks to national TSOs and BEIS data.

Electricity no energy yes. It's 17% of the danish energy usage. Not sure what you want proof of.

Wind and solar are intermittent sources which makes them seasonally irregular and requires backup energy from other more stable sources such as coal, oil, gas and nuclear.

https://www.windpowermonthly.com/article/1490548/danish-wind...

http://cphpost.dk/news/scorching-summer-causes-electricity-p...

You claimed “Last year Denmarks weather was amazing, which meant no wind at all.“ then went on to talk about coal, this was explicitly about electricity generation. Your claim was absurd and provably false. We can have a civil and normal discussion about the downsides of renewable intermittency if you want, or you can make absurd claims like that and I think most people will take you for some kind of crank.

What are you talking about? Last years weather were amazing and Denmark did get electricity from coal in germany. If you want ti have a civil discussion perhaps start with yourself. This is not something i am making up.

The solution seems to be diversity in supply. In 2017 Denmark had 45% wind with a total of renewable being 66%. The imports are mainly from Sweden and Germany, (possibly Norway) where renewables (hydro and wind) and nuclear dominate. Denmark has a significant portion of coal in district heating, but the portion is also shrinking.

https://en.m.wikipedia.org/wiki/Electricity_sector_in_Denmar...

Be careful here. Thats electricity not energy. Electricity is only around 20% of the energy needs.

The person I replied to talked about electricity. Yes, the energy supply is different. Electricity seems to supply about 17% of energy consumption in Denmark. I was trying to be brief. https://en.m.wikipedia.org/wiki/Energy_in_Denmark

Ok. It's just that people seem to always confuse energy with electricity (not saying you are but people in general) and just want to make sure it's clear otherwise it would give the impression that Denmark (or Germany) somehow found a way to solve their energy needs through alternative energy. They haven't not even by a longshot and it's made it more expensive which might be fine in rich countries but definitely isn't a recipe for the poor countries.

Indeed. We do have to solve the issue for everyone though, or we are hosed.

The problem is scientific not just technology optimization though. Wind and solar just can't deliver, they are linear solutions to exponential problems. They do around 1% today only expected to be 3-4% in 2040 and that's with the current energy need which will increase significantly in as more people become middle class.

So we need something groundbreaking with high energy density and scalability and which is cheap.

There is a tradeoff between how many batteries and power-to-gas plants you need and how large your excess production and how well connected you grid it.

So... average household (in America, anyway, don't know about UK) uses a little more than 10,000 kwh of electricity per year... one kilowatt-hour of electricity creates 1.1 - 1.2 pounds of carbon dioxide... so each household emits maybe 6 tons of CO2 per year from electricity usage.

So if this is 1 million homes, that's 6 megatons of CO2 saved per year. The world emits 37 gigatons per year. So this saves 6/37,000, or ... I just got depressed.

Every (very little) bit helps, right?

Yes, we just need to build about 5000 more of them. Or 2500 wind and 2500 solar. It's possible -- there are lots of facilities we have 5000 of in the world. For example, there are more than 5000 airports with passenger service, all built in the last 110 years.

If you go by number of turbines (which you shouldn't since these are probably way bigger than average), the US currently has about 325 of these farms.

According to the google summary of this paywalled article (https://www.washingtonpost.com/news/wonk/wp/2012/12/08/all-o...) there are 62,500 plant in the world, so 5000 more of these seems pretty doable. And most of the world uses less energy than an average American, so it would be less on average.

Your calculation is a bit pessimistic because electricity is a much higher quality energy than what you get from burning fossil fuels. For example, electric cars, from wind turbine to movement, are maybe 70-80% efficient. ICE cars from gas station to movement are maybe 30% efficient (now add in the cost of extraction and refining). Similarly, heating your home by burning oil you get a little less than 1J of heat per Joule-equivalent oil burned. But with a heatpump you get 2-4J of heat for every Joule of electricity.

The economist had an article about this too: https://www.economist.com/britain/2019/09/21/lessons-from-br...

The engineer in me wishes there were more hard numbers, like "what is the operational cost of the wind farm?"

One of the fun exercises to run would be a win farm that was powering a submerged data center (so that it could dissipate heat into the ocean).

The Google data center in Hamina, Finland makes use of seawater for cooling, I believe. https://www.google.com/about/datacenters/locations/hamina/

Google also had experimental sea cooled servers in the bay for a while. I'm not sure if they're still running that program.

1M homes, or three bitcoin mining ops.

Incidentally this wind farm was the largest contributing factor to the blackout in London a few weeks ago when it decided to shutdown during a transient cause by a lightning strike, subsequent transmission line trip, and 200 MW of generation tripping. Then Hornsea wound down 700 MW. Some software change performed the next day apparently fixed the problem.no details on what it was though yet, or why the 200MW steam turbine also tripped.

It's clear now that we'll be able to power much more of our power needs by using wind and solar. More 'exotic' schemes today like using the tides might not even be needed, but we'll see.

Great spell checking CNN Business. "is located farther out to see than any other wind farm"

I’m curious what’s the effect of interfering with the wind patterns?

Possibly localised ground level temperture increase of a fraction of a °C due to air turbulence relocating warm air.

Fair question. Some rough maths incoming..

There are 174 turbines in an area of about 300 sq km. If they were laid out on a grid the grid size would be about 1.3 km. The blades have a diameter of about 24 m.

Feels to me like that's far enough apart to not massively affect the wind.

I have never felt the wind reduce around a wind farm before. Each wind turbine is like needle in a haystack of wind, I can’t imagine anything actually measurable.

They said in the article that this wind farm is the size of Malta.

Malta itself is pretty small - smaller than many European cities.

How much does Malta slow down the wind?

I'm curious.

Have you actually done some formal measurement in front of and behind the wind farm?

Because the way you're writing suggests not.

Btw turbines do slow down the wind and it is measurable, turbines at the back produce less energy than those at the front, wind farms are laid out specifically to try and avoid this.

https://www.researchgate.net/publication/242580464_The_Wind_...

Sure, if the turbines are spaced too closely they will lose efficiency. But as far as the surrounding environment is considered, existing wind farms don’t have any noticeable effects on the wind. Perhaps when we start building bigger more consequential wind farms we will notice something.

At our current level of technological know how, we could never hope to capture that much wind.

Just a wild guess, but probably no where near as much as large buildings or large power plants with cooling towers.

I find it very strange that this comes up from time to time with windmills, but not say, New York City. I'm sure it does something but it feels like "an extremely fluid material being redirected in a relatively small way in an extremely localized area" isn't really super important?

I could be entirely wrong and maybe changing the wind pattern will be the "pulling hydrocarbon liquids out of the ground and burning them" of 2119.

I thought of this too.

One way to approach it, is what % of the total wind in the world would it take to power 100% of our energy needs? If it is something like 50%, it seems like it would be very possible for large scale wind to eventually do something to our wind patterns. If it is something like 1% or .01%, it seems pretty unlikely to do much. (part of this assumes you would never power 100% of your energy needs with wind due to variability).

I agree that if we were to supply significant portions of our energy need with wind power, we would be taking that amount of energy out of the global climate system and therefore alter temperature/air pressure/wind in some combination (that is, alter currents). We could also look at it as a percentage of available energy in global wind (see http://www.wse.ie/how-much-wind-energy-is-there for a take on this).

That said, I don't think we can necessarily assume that 1% or 0.01% would have a small effect. Small perturbations can have large impacts in complex systems. It is possible impacts could be significant in localized ways as well (for instance low change in global average temperature but greater incidence of hurricanes).

Gosh, there are currently 5 responses to your question and every one is pure speculation.

Folks, if you don't know the answer, don't answer.

And now there's one scolding people for commenting...and one pointing out that scolding. Helpful!

Saying something true is more helpful than speculating without any data whatsoever.

It's an attack on clean energy... I'm sure there's got to be a way to discredit it... it doesn't matter if I make it up!

I don't know man?

In this case, giving the numbers of how much we'd need to harness to have an effect is pointless. We aren't really in any kind of a place to grasp the enormity of the numbers. Numbers that big really do become meaningless.

Wind is just second order solar energy. Massive amounts of solar energy make it to Earth in a given year. I suppose if you must have a number, we can work in either kWh or BTUs. Won't really make a difference to the enormity of the outcome though.

For instance, in BTUs, about 80 million british quads of the energy that the sun gives earth will make it to the surface in a year. (I know the sun delivers more than 80 million british quads, but I'm not counting the 30% that gets reflected). Now I'll be nice, and say an additional 10-20% of that is absorbed by biomass. (It's not, it's way closer to 10%, but I'm being nice.) And an average American home uses what? say 50 million BTUs a year, (About 12 - 15 thousand kWh), if they're being profligate?

So the wind is coming from the interplay of the solar energy absorbed by different areas of the ocean and different areas on land. (Another caveat, our atmosphere can trap some of the energy, which will add to new energy sent by the sun, and kind of spiral in that fashion. This is what happened to Venus, which is why they have like 500 mile an hour winds there.) In any case, ignoring the climate warming, we'd have to find some way to harness enough wind to make an impact against, say, 20 million british quads of BTUs.

Yeah. That's not gonna happen.

This is what I mean by incomprehensibly massive numbers. Basically, we'd have to harness enough wind to power roughly 5 billion groups of US homes, where each group would contain about 1 trillion US homes each. That would be just to have a 1 percent impact on the energy in the winds on this planet in a year. And the required number goes up with global warming, because more wind.

At this point we're talking monopoly money man. It's meaningless. Again, we don't have the smarts or technological know how to do anything even close to that, and don't really have any kind of frame of reference as a species to meaningfully ponder the implications of such enormous numbers and amounts of energy. Even thinking about it only makes you consider the smallness of mankind.

> We aren't really in any kind of a place to grasp the enormity of the numbers. Numbers that big really do become meaningless.

If that's true, that's all the more reason not to comment.

You're saying we can't grasp the numbers, but apparently you think you can grasp them well enough to conclude that humans won't have a significant effect.

If we really can't grasp the numbers, then the only conclusion we can come to is that we don't know. I think "I don't know" is something that we need to say more often if we're being honest with ourselves.

> For instance, in BTUs, about 80 million british quads of the energy that the sun gives earth will make it to the surface in a year. (I know the sun delivers more than 80 million british quads, but I'm not counting the 30% that gets reflected). Now I'll be nice, and say an additional 10-20% of that is absorbed by biomass. (It's not, it's way closer to 10%, but I'm being nice.) And an average American home uses what? say 50 million BTUs a year, (About 12 - 15 thousand kWh), if they're being profligate?

> So the wind is coming from the interplay of the solar energy absorbed by different areas of the ocean and different areas on land. (Another caveat, our atmosphere can trap some of the energy, which will add to new energy sent by the sun, and kind of spiral in that fashion. This is what happened to Venus, which is why they have like 500 mile an hour winds there.) In any case, ignoring the climate warming, we'd have to find some way to harness enough wind to make an impact against, say, 20 million british quads of BTUs.

Back-of-napkin math is pretty unconvincing. For example, you made no mathematical connection whatsoever between the energy from the sun numbers you were throwing around, and the amount of that that gets converted into wind energy. You said that 80 million quads of energy hit's the earth from the sun, so your "20 million British quads of BTUs" is arbitrarily choosing to say that 1/4 of the sun's energy is converted to wind?

So let's sanity check that. quads is a unit of energy E, and E = 1/2 x m x v^2

Now let's convert our numbers into reasonable units and plug them into the equation. 20 million quads = 2 x 10^7 quads. 1 quad = 1.055 x 10^18 joules[1], so that's 2.11 x 10^25 joules. The mass of the earth's atmosphere is 5.15 x 10^18 kg[2]. Plugging these numbers into E and m in the equation, we get:

    E = 1/2 x m x v^2
    2.11 x 10^25 = 1 / 2 x 5.15 x 10^18 x v^2
    2.11 x 10^7 = 1 / 2 x 5.15 x v^2
    4.22 x 10^7 = 5.15 x v^2
    2.1733 x 10^8 = v^2
    14700 = v

Just to be clear, joules is kg x m^2 / s^2 and our mass was in kg, so this velocity is 14700 m/s. You guessed that 20 million quads of the sun's energy was being converted into wind, but if that were true, the average velocity of the earth's atmosphere would be 14700 m/s. To be clear, that's the average velocity, and we know that wind isn't uniform throughout the atmosphere, so some parts would be faster. For comparison, the speed of sound in air is 343 m/s.

So yeah, the numbers you are using are incomprehensibly large because they are wrong, wrong, wrong by a few orders of magnitude.

To be clear, this isn't a criticism of wind power. It's obvious that the clear and present danger of global warming is a much more pressing concern than unknown effects of wind power. It's a criticism of people answering questions they don't know anything about.

[1] https://en.wikipedia.org/wiki/Quad_(unit)

[2] https://en.wikipedia.org/wiki/Atmosphere_of_Earth

While I was calling you out for essentially making up numbers, I noticed that my [1] link above contains the global energy consumed in 2004. I decided to look for more recent numbers, and on this page[1] found that estimated world energy consumption was 5.67 x 10^20 joules.

Let's convert that to wind speed:

    E = 1/2 m x v^2
    5.67 x 10^20 = 1 / 2 x 5.15 x 10^18 x v^2
    5.67 x 10^2 = 1/ 2 x 5.15 x v^2
    1.134 x 10^3 = 5.15 x v^2
    2.2 x 10 ^ 2 = v^2
    14.8 = v

So we'd expect that if all the world's energy came from wind, it would reduce wind speed in the world by an average of 14.8 m/s.

For comparison, average wind speed in Chicago, the windy city, from 2010 to present was 9.9 miles/hour[2] = 4.43 m/s.

Before you lose your calm, and conclude that wind power is evil, let me reiterate, back of napkin math STILL shouldn't convince anyone of anything. I'm merely posting this to show that back of napkin math can be used to calculate much different results.

[1] https://en.wikipedia.org/wiki/World_energy_consumption

[2] https://wind.willyweather.com/il/cook-county/chicago.html

I think that you missed a time term somewhere. You're looking at global energy use for an entire year. Don't you want to normalize that to joules used per time period (i.e. power) before determining how it affects instantaneous-average wind speeds?

The lowest published estimate I have seen for extractable global wind power [1] is as little as 18 terawatts in the paper by Miller, Gans, and Kleidon:

"Estimating maximum global land surface wind power extractability and associated climatic consequences"

https://www.earth-syst-dynam.net/2/1/2011/esd-2-1-2011.html

18 terawatts happens to be exactly equivalent to an annual energy output of 5.67 x 10^20 joules.

18 terawatts is the low end of the estimated range in this paper; the upper end is 68 terawatts.

[1] The authors only considered wind farms placed on land, perhaps because offshore wind was so much more expensive in 2011. Their lowest estimate is too low, even if you stick with the rest of their methodology, after adding offshore wind.

> I think that you missed a time term somewhere. You're looking at global energy use for an entire year. Don't you want to normalize that to joules used per time period (i.e. power) before determining how it affects instantaneous-average wind speeds?

Nope. I may have messed up my calculations somewhere, but I'm quite confident in my equation (kinetic energy E = 1/2 x m x v^2).

That paper looks pretty interesting, but I'm going to follow my own advice and admit I don't know: I don't have the background to evaluate the validity of their atmospheric model. The conclusion[1] is pretty important if it's true.

[1] "Furthermore, we show with the general circulation model simulations that some climatic effects at maximum wind power extraction are similar in magnitude to those associated with a doubling of atmospheric CO2. "

Parent is correct. You've calculated that a year of energy consumption is equivalent to the kinetic energy of the atmosphere moving at 14m/s.

This says nothing about how energy flows through the system, which is what will determine the impact on wind speeds.

> You've calculated that a year of energy consumption is equivalent to the kinetic energy of the atmosphere moving at 14m/s.

> This says nothing about how energy flows through the system, which is what will determine the impact on wind speeds.

shrug

I'm not gonna teach you guys high school physics. You can look up E = (1/2)mv^2 in any Physics textbook or your favorite search engine.

Before you disagree further, try calculating this yourself. Look up how to calculate the final speed of an object from kinetic energy. Make sure you plug energy units (i.e. joules) into E and power units (i.e. watts) into P. This isn't hard math, and the necessary equations are all over the internet.

The value you plugged in was a year of energy consumption. Why not a day, or a century?

If you used the former, it would tell you that wind speed would be reduced by 0.04m/s. If you used the latter, 1.4km/s.

You're not using the equations incorrectly, but they're not telling you what you think they are.

They are telling you - if we store up all the power use of humanity for this length of time, then use it to blow the air, how fast will it go.

> The value you plugged in was a year of energy consumption. Why not a day, or a century?

...because when I pulled the number from wikipedia it said it was the energy consumption for a year, not for a day or a century.

> You're not using the equations incorrectly, but they're not telling you what you think they are.

> They are telling you - if we store up all the power use of humanity for this length of time, then use it to blow the air, how fast will it go.

...no, it's telling me if we collect the energy used by humanity during this length of time, then use it to blow the air, how fast will it go. You cannot use "energy" and "power" as if they were interchangeable, they are not.

What you may be missing is that these physics equations go both directions. If we take the blowing of the air and use it to produce the energy used by humanity during this length of time, we'd expect to see the same decrease in speed.

There's nothing wrong with my sentence. It might be a bit informal, but "power use for a length of time" is a quantity of energy.

The decrease in speed you're describing is one time, not continuous. This is the issue both parent and I are pointing out. It's a shame to me that you aren't willing to see your error and instead resort to nitpicking, but I'm not going to try to explain a third time.

IIRC, there's a theoretical limit to how much energy even the most efficient windmill can take from the wind. It's close to 50% - maybe 53%? That's one turbine taking energy from the cross-section of the wind that intersects the area of the turbine's blades. You'd have to look at what fraction of the air you care about intersects the turbines, and multiply that by that 50% (or whatever the real value is for the actual turbines in question).

That's if you care about energy. If you care about vortexes and disturbed flow... I have no information.

Betz's Law, and the figure is 59.3%.

It has ~zero impact on wind patterns. They have a tiny reduction in wind speed, but the moving column of air is generally 10 to 100+x as tall and very wide. https://www.aviationweather.gov/windtemp

More critically they have zero impact on the forces that actually generate wind in the first place.

How many birds is this going to kill? I've read somewhere it's not that nice to them.

If that's the metric, we need to outlaw letting cats outside.

True, wind farms kill birds. But other things do too. (Apparently birds have a lot of things out to kill them.)

https://science.howstuffworks.com/environmental/green-scienc...

Don’t believe everything you read. Bird death from turbines is essentially nothing next to bird death from hitting buildings, or, worse, cats.

It’s a persistent myth, and recently back in vogue due to the tweeting of a certain orange personage, but wind farms as bird-destroyers are not worth worrying about.

Agree that the wind turbine thing is overblown.

However, according to the Royal Society for the Protection of Birds, there's no evidence cats are causing problems for bird populations in the UK at least.

https://www.rspb.org.uk/birds-and-wildlife/advice/gardening-...

This might be different elsewhere though.

Not a myth. Look at the birds being killed, not the numbers. Not the same bird species being killed by wind farms and buildings (or house cats)

And the bats are at risk too https://www.oregonlive.com/environment/2019/09/oregon-state-...

I don't like Trump, he is mostly wrong, but pretending absolutely everything he says is wrong, is a dangerous proposition.

I still think these wind farms are vastly positive, but we should recognize the problem with bird populations, and find clever ways to mitigate it, instead of putting the question aside just because "the bad orange men" said this was happening.

https://link.springer.com/article/10.1007/s10344-018-1192-z

Reply on news.ycombinator.com