Solar and wind can meet world energy demand 100 times over | Hacker News Reader

Solar and wind can meet world energy demand 100 times over

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69 pointsbillyharris43 comments

There are a lot of ways to generate lots of power, what we're generally lacking is ways to _store_ power to handle things like peaks.

We know a lot of ways to store power. The trick is storing it efficiently. If we have enough surplus power (which may be the case in a few years), efficiency becomes less important.

Just as an alternative to prioritizing storage (we should still do it, but it's not the only constructive use), we could use a lot of excess electricity to create hydrogen, desalinate sea water and pump it inland, create biochar without kickstarting the heating process via combustion, etc.

The hydrogen could be used for hydrogen vehicles and other purposes. Seawater desalination (very partially) addresses sealevel rise while also getting water to dry areas. Biochar sequesters carbon while helping more plants to grow with less water and less chemical fertilizer.

So from a certain point of view, the above pursuits are like investing most of your "excess money" in the stock market rather than putting most of it in a savings account. And since we're starting to address climate change so late we need something better than just a savings account or battery.

Imagine a san Joaquin valley that feeds everyone/doesn’t lie fallow, and yet the rivers run free, and the delta smelt can live. Oh and California’s native salmon runs come back.

The difficult part is storing it on the kind of massive scale required full stop. Sacrificing efficiency can only do so much to help solve this, especially since the wasted energy has to go somewhere and dealing with that has its own costs...

A lot of these problems solve themselves with proper pricing. For example if power is nearly free during daylight hours and expensive in the evening, businesses will shift some percentage of energy intensive operations to daylight hours. EV charging stations will charge more during evening hours.

Charging EVs during daylight hours while they are parked at work places instead of overnight at employees homes is another way we can shift use. Some of these things might be done via pricing, others perhaps government incentives.

Storing power doesn't seem like an intractable problem. With the huge incentives with the coming electric car market, technology, renewables storage and god knows what else, I imagine there will be a lot of investment pouring into solving this. It's only a matter of time.

Well if you generate enough excess power, you hardly need to store any.

This makes no sense.

Without storage excess power is useless at best, dangerous at worst.

Now you shifted the problem to power transmission, because there's no way to generate an excess of power at all times in all locations using just wind and solar.

So while in my region at the time of posting this, 100% of electricity is generated by wind, there'd be 100% less if there was no wind (which happens from time to time).

Solar wouldn't help either, because right now it's dark outside and it will stay dark for another 6 hours.

So right now, even if there's an abundance of power generated elsewhere, it would have to get transmitted efficiently to here (and from here to where it's needed if applicable).

Local storage and massive interconnected power transmission capacity is what's required. And that ain't cheap.

My point is that if you have enough of something, it stops mattering as much how efficient you are with it.

Unfortunately no. Whatever power you generate you have to send somewhere. Excess generation will push the grid frequency high and destabilize the grid in much the same way that insufficient generation will pull the frequency down and destabilize the grid. Storage doesn't just provide power during low generation, it provides somewhere for power to go when generation outpaces demand.

This doesn't sound right.

With solar a small solidstate relay can disconnect individual panels as required, or a larger relay can disconnect strings of panels.

I was replying specifically to the "It doesn't matter if we just make enough" idea. For solar panels on a site scale you can use variable pitch panels focused on a solar collector to control your output power if you are peaking to high. Wind can use variable pitch turbine blades. Both of these configurations add a lot of cost but are worth it when talking grid scale generation and aren't uncommon in practice. The actual power you put onto the grid does need to be matched to how much is being used. Storage (hydro is the most popular it doesn't have to be batteries) allows for cheaper generation because you have a lot more options for burning off overshoots and peaks with the benefit of smoothing out dips. Without storage all of this together gives rise to weird things in practice like California selling power at a loss to Arizona and then buying it back because of the combination of subsidies and grid stability.

If generation outpaces demand enough and there's nowhere to put it, can you not just send some to ground? Or reduce your generation?

Consistency is the reason to store, not amount. The sun doesn’t shine at night and the turbines don’t spin without wind (which also is more likely at night). Modern society is built on always available electricity, and some things absolutely require them (eg a data center).

The world can theoretically meet it, in practice, it is the same situation as the "food" shortage.

Solar and food have a distribution problem, not only a generation problem, but since the world decided nationalism, protectionism and populism is more important than cooperation it is not going to get solved and we'll have to generate our needs and store it many times over in order for the biggest consumers of energy to be satisfied.

Just in time production and energy sharing will remain a dream and we'll keep wasting resources and the planet again and again just for our petty grievances.

I worked to help develop and deploy geothermal for a few years. Like most alt energy, it is was never intended to be the single replacement for fossil fuels.

But deployed to it's strengths - geothermal is yet another valuable component, that can advance the honest goal of marginalizing fossil fuel use.

It feels like within the next 20 years we are going to have a good handle on “green” power to fixed locations. The tricky piece we have left is how do we move people and freight over long distances.

EVs can do a decent job of transporting a few people a short distance, but aircraft and long distance freight has a whole other set of issues.

Look at container ships, one of the biggest polluters and sources of carbon on the planet. How do you remove the need for massive amounts of diesel on those?

How about passenger and air freight? How do we eliminate all the CO2 from jet fuel? In the US we are terrible at infrastructure, but do we invest in a super-train system?

This is likely the next big challenge.

If you talk to Airbus, the current plan is hydrogen, which is emission free, besides water. Since you can extract it from water by electrolysis, there is an essentially endless supply, assuming you have endless clean electricity.

Hydrogen power is fundamentally a power storage technology. It makes sense to use H2 for that. I've seen some technology that transforms CO2 into jet fuel which is another somewhat carbon neutral technology.

Container ships are massive emitters of some pollutants like SO2, but not CO2.

Sources usually put the carbon number at around 3%.[1] this number has been rising in part because the denominator, global carbon emissions, has been falling as power has been emitting less.

[1] https://www.transportenvironment.org/what-we-do/shipping-and...

"100 times over" is a lot less than I'd have thought or hoped.

We have to cover 1% of the world's surface with solar and wind farms to pay for our current energy use? That won't be easy.

Anyone breaking even usage-wise with rooftop solar is already much of the way there, and that's excluding utility generated power and big savings from improved home design (e.g. passive solar heating) and other technologies not yet well deployed like ground source heat pumps and air source heat pumps. Once people realize that these technologies are cheaper than the current go-to options, things will happen quickly.

I'm not very optimistic that we have enough time, nor individuals have enough financial resources, for the market to realize how cheap / efficient these technologies are. We really need this progress implemented as part of large scale systemic programs. The market is simply too slow.

I don't understand rooftop solar as a large scale solution. We don't propose that every household grows its own food or mines its own ore.

Let us build solar panels on the least valuable rural land, and benefit from the economies of scale and the ease of installation and maintenance - better to look after one acre of solar panels and inverters than the same number spread over a hundred houses. Transmission losses are negligible, easily single digit percent for 100km.

For individuals, it may make sense if they value grid independence or if they can benefit from tax breaks imposed by a government that doesn't agree with my take.

> I don't understand rooftop solar as a large scale solution. We don't propose that every household grows its own food or mines its own ore.

We do, OTOH, demand that every housing unit have, say, flush toilets, because the waste problems without them cause a negative externality we don’t want to deal with.

Solar panels can be viewed as the same thing with regard to electricity use.

> Let us build solar panels on the least valuable rural land, and benefit from the economies of scale and the ease of installation and maintenance

Shading rural land with solar panels makes it less valuable for the one thing rural land is most likely to be valued for.

Putting solar panels on rooftops doesn’t compete with other uses of the space.

For me the power of rooftop solar is that I don't need to wait for political consensus that something needs to be done.

I can do it myself. Now.

> I don't understand rooftop solar as a large scale solution.

Here's something that might help, then. I have rooftop solar and its lifetime cost (labor + parts) is lower than the price of electricity, meaning it's cheaper to have solar than to not have solar. Secondly, the book Drawdown lists solar farms as the #8 solution and rooftop solar as #10. So rooftop solar is more than financially feasible, and necessary from a climate perspective.

I see your point about economy of scale. I’d rather that rural land be re-wilded so other life can flourish on it, towards resilience as climate changes. The US used to be home to millions of beavers (per book “Eager”), the real heroes of the Yellowstone recovery story (where wolves were reintroduced). The Lewis and Clark expedition noted a hundred miles of continuous wetland in the Midwest. Beavers help prevent flooding, too.

Decreasing demand for energy feels like an important step on the path to a healthier ecosystem, and withdrawal will be tough for many. I also propose that more people do grow their own food, or at least be much closer to the farm and garden.

The next problem to solve is how to continue servicing demand for electricity when the sun goes down (an everyday occurrence) and when the wind stops blowing for extended periods of time. Demand for problem is constant, however the electricity generated from solar and wind is not always so.

Serious question. How do we make enough solar panels and wind turbines that will be capable of producing all of this energy without destroying all of our natural resources/habitats?

Reminds me of a joke: This machine does the work of 10 men. Unfortunately it takes 15 men to operate it.

It's a funny joke, don't get me wrong. But I'll take the 15 men sitting behind a computer operating remotely a digger inside a mine instead of 10 men breaking their backs and probably risking their lives with a shovel.

Not to mention what do we do with old solar panels after they've lived their life. There's going to be a lot since a lot is needed to generate the amount of power needed. There's a good chance it will just get shoved onto some 3rd world country for them to deal with.

Could they be renovated to serve lower power items like street lamps?

And where do we build them? Because where I live, in order to have them installed, whole chunks of forests are being wiped.

Where is that?

Germany, region of National Park Eifel. These things stand even in the park. They’re taller than trees around.

That problem doesn't seem any more significant for wind and solar than other powers sources: mountain top removal for coal, transporting tons of coal in diesel trains, building (and eventually disposing of) giant power plants, etc.

I can't help but wonder, "what's the point?", if this is all going to result in the destruction of our natural habitats in the end anyway.

Wind and solar results in much much less destruction of natural habitat than fossil fuels.

I'm not up to date on current industrial-scale solar cell manufacturing processes, but doesn't the manufacturing proccess still require massive amounts of coal? And what is the lifespan of the cells before they have to be replaced with new cells that also require coal to be produced?

On the battery side, I'm pretty sure that industrial-scale production still requires mining and mountain top removal. And what are wind turbines made out of? Where are we getting those resources from?

Like I said, I'm not up to date on the state-of-the-art industrial manufacturing processes required to make solar cells / turbines. But I'm pretty sure it will still require massive habitat destruction and the release of unimaginable amounts of greenhouse gasses to get us where we need to be.

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