Exploring strategies to decarbonize electricity | Hacker News Reader

Exploring strategies to decarbonize electricity

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174 pointsjanober135 comments

From the simulations website:

"A megawatt-hour of electricity is about the amount a household uses in a month."

That is the elephant in the room. Our household of three adults can comfortably live on about one sixth of that amount.

Who can tell me with a straight face that living comfortably on three times our electricity consumption is impossible, even in a harsher, less moderate climate? That alone would reduce US household consumption by 50%!

I applaud Google for coming up with this tool. I also hope it will open its eyes to the feasibility of changing people's consumption patterns.

The elephant in the next room however is the couple of billion people who are pining for a sliver of the middle class (read: high energy) lifestyle we've taken for granted for close to a century. It would be grossly immoral to deny this lifestyle to them (never mind geopolitically impossible).

Sure, they get to skip a few steps on the ladder, and start out with LED lights and cheap insulation materials etc, but an energy efficient dish washer is more expensive than a less efficient one, and a well-insulated house is more expensive than one less so.

Yes, we should keep demanding better and more efficient solutions, to make sure they get developed, but the only responsible thing to do is to prepare for a future where global energy consumption is going up by quite a bit.

And the elephant in the third room is electromobility.

1MWh charges a Tesla Model S with a 100kWh battery 10 times, giving you 5400km of range.

If two people in a household are commuting 135km/day each for 20 days/month in a Tesla Model S, electrical energy consumption of the household doubles.

That elephant is not in the room yet. It's waiting at the Supercharger station a couple hours out on the highway, and won't be here for a quite some time. While that's changing with the Model 3 and the responses of other auto manufacturers, few people own or can afford a Tesla Model S. The elephant that's currently in the room is gasoline-based mobility.

5400 km in a gasoline-powered vehicle at 20 mpg or 14 liters per 100 km is 756 liters or 167.8 gallons of gasoline, and at 33.7 kWh per gallon, that's 5.655 MWh.

The commutes multiply the energy consumption by more than a factor of 5. You shouldn't feel good about turning off an LED bulb and using a lamp instead if you also enjoy driving to work in your pickup truck.

"If two people in a household are commuting 135km/day each for 20 days/month in a Tesla Model S, electrical energy consumption of the household doubles."

This is a big problem if everybody wants to charge at peak times. But most people charge overnight. Smart chargers and smart grids will ensure that loads get balanced and there isn't a huge spike in demand at 7PM when everyone plugs in as they get home from work.

In a future where grids are supplied largely by renewables and nuclear, EVs will benefit the grid by soaking up excess supply at off-peak times. When they're plugged in, they're effectively storage batteries on wheels.

absolutely this! IMO the energy conservation and carbon cost of electricity philosophy focuses attention on the wrong problem. The right problem to solve is how to generate more energy cheaper and with less harm to climate.

When I was growing up, we had neither heating, nor cooling. Summer temperatures would hit 40 deg Celcius. Winter temperatures would hit 1 deg celcius. It was supremely uncomfortable for much of the year and an active distraction against achievement.

Now I am well off and lead a comfortable life with climate control at my fingertips should I desire it. I would not willingly go back and definitely not have my child grow up that way.

There's one relatively simple method: if electricity cost more, it would be easy to justify investments in energy saving.

On the other hand, if the cost of things currently roughly depicts the environmental impact the things have, then it might not make sense to invest in energy saving with current technologies as that could have a very long payback time in environmental impact too.

I believe this is already the case in California. The most expensive energy by kWh but the lowest energy bills because of a statewide commitment to energy efficiency.

A carbon fee/tax/floor would be required to make things reflect their true cost in terms of climate change, this can be simulated in the app. Note that this isn't spending more money (at least up to the estimated social cost of carbon), since due to the externalities that cost is already being borne by sociery

Many Californians live in parts of the state where there is not much need for heating and cooling much of the year, which also helps keep consumption down.

A megawatt-hour is 1.38kW continuous consumption.

It's not hard to imagine how a household could use that. Two long how showers per day per person, air conditioning / heating, a pool heater, a fridge, another fridge in the garage, a deep freezer in the back room. Some people have multiple always-on PCs and screens.

And now we're expecting everyone to recharge their car at home too.

It's not difficult to imagine how a US household could use a MWh of electricity per month indeed. We know these are the facts.

Point is, it is possible to change those consumption patterns. Quoting from your example:

* heating: 67°F should be fine in winter. replace by natural gas where possible. invest in appropriate insulation and ventilation. Look at how much of northern Europe does it.

* air conditioning: use less and more recent airco. 76-77°F should be fine in summer.

* pool heater? just switch it off, or at the very least switch to a more efficient source of heating

* cut the second fridge in the garage, or at the very least, replace it with something efficient

* use an efficient freezer

* Check what machines have to be always on. Use something efficient for the things that really have to be always on.

I'm quite sure something along these lines would have cut more than 2/3 of the electricity consumption of this average American household.

It is physically possible to make these changes. I concede that it would not be easy to convince the people to actually make changes in this direction, but it can be done!

"heating: 67°F should be fine in winter. replace by natural gas where possible."

Replacing electric heating with natural gas isn't really valid as a long-term carbon solution. Certainly it's more efficient than using electricity produced from fossil sources, but it won't benefit from future grid improvements/decarbonisation. Heat pumps can deliver efficiency/cost comparable to gas in many countries.

Natural Gas heating is very common in the UK, but we're going to have to get rid of it eventually to meet climate goals.

The very low cost of gas also encourages people to burn more of it and overheat their homes (not uncommon to see flats with the boiler running and the windows simultaneously open for ventilation!). If we were thinking long-term, as you said, we're better off investing in better insulation and ventilation (MVHR).

> * pool heater?

This has to be the biggest offender of all the mentioned items.

The lower bound of heat required to raise the temperature of a 10mx6mx2m pool by 5 degrees Celsius is 700kWh, that's over 200kWh in electricity using a heat pump.

Yeah, my Dad has an outdoor pool with a heat pump, and the electricity bills are eye-watering. Thankfully he's now seriously looking at installing solar PV.

>solar PV

Fyi solar pool heating is a much cheaper option. They sell inexpensive unglazed plastic collectors specifically for this purpose. Reducing or eliminating that pool heating load should dramatically cut the PV system cost.

http://www.builditsolar.com/Projects/PoolHeating/pool_heatin...

Yeah, the pool actually did have this type of solar thermal heating originally, when they first bought the house around 15 years ago. But it wasn't very effective at heating outside of the peak summer months. Installing the heat pump meant they could swim around 5-6 months of the year instead of 2-3.

But to be fair, the collectors probably weren't big enough for the size of the pool. And the technology has probably also improved a lot since then - it was a pretty ancient set up.

PV is certainly more expensive but it has other utility besides just reducing the pool heating costs, as it will be able to generate reasonable energy year round for them (at ~45 deg latitude). If they didn't already have the heat pump then thermal might make more sense!

Or don't use AC altogether. Continuous AC always all-the-time is a very American thing.

I'd rather give up meat than AC, and I'm a meat lover. But I'm in the deep south, sure I'd give up AC in CO.

Makes sense for the South in summer months, sure. But in the USA as a whole, AC is used and abused even though there are solutions that involve building materials, behaviour and good habits that could make life livable. Temperatures get crazy high in Europe as well (40C or 105F is not uncommon in summer months in Spain or Italy and they do without AC). Using terra cotta, washing your floors, good use of shade, plants and trees, all that goes towards managing heat. Though the humidity in the southern US states does make it way more complicated, I'll give you that.

Not keeping shopping malls at freezing temps would help, too!

I used to think this until I spent some time in the tropics.

I folded u my temperate-climate clothes and put them away. They all went mouldy.

Although, I suppose that's just a knowledge / behavioural issue.

I propose a new type of economic system powered by crypto computing. A system where those that pay out the least in expenses get paid the most basic income. You could then normalize the distribution to avoid an inequality problem and overly harsh punishments.

You turn each BI account into a bank. So I can pay with my BI as a debt using an escrow account. The payee could then redeem the value for cold hard cash, or if they hold it and use it as money they get interest based on the value I continue to add to the account.

An expense is a payment using BI that is redeemed for value instead of held as currency.

This would encourage good savings patterns and also encourage lowering the potential debts that might become redeemed. This empowers the service providers to punish overusage of resources by redeeming values instead of holding them. You could also build into the contract an enforcement to just punish those that use the most resources by auto redeeming there values.

In the end these punishments don't kill people, but they should incentivise more humans to lower the amount of resources they use with that slight gamification.

The point is not that it's hard to imagine; it's that it can be considered normal. Why would people take two long showers every day?! Or leave screens turned on all night at home?

I gave up asking my partner to close the bathroom and bedroom doors when she is at home during the day with the heat pump set to 25 degrees C. It causes the heat pump to run flat out because it can't deal with that much hear loss.

And she's one of these save the whales type. And she wasn't working (receiving welfare) and I was paying the utility bills.

So I asked her to move out. Which doesn't solve the problem, just relocates it.

Point being, people don't know. And that's ok, there's plenty of stuff I don't know. We just need to engineer solutions to these problems. And maybe some of that is social engineering. But in the mean time: I give up.

spot on. But now, how do you make people accept the new normal in the (idealistic) time frame required by COP 21 goals ?

Pool heater? 3 fridges? The world wouldn't support this.

Does that include heating and hot water?

I consume ~8MWh/year in the UK. 1.5MWh of that is electricity, but the other 6.5MWh is gas mostly used in the winter months to keep warm. I set the temperature in my house to 17C (63F). I did go through a previous winter at 15C, but it just became too uncomfortable.

Another aspect of this is the fact many of those devices release a significant amount of radio frequency interference. Although mostly amateur radio operators and shortwave radio listeners are mostly affected that RFI does affect other electronics such as lights and TVs. Frankly, I wish the US govt would enforce its laws on energy efficiency and RFI more because they're not really that mutually exclusive barring switching power supplies (but even that to my knowledge is becoming less true as the regulator components are becoming even better at not producing as much RFI across the HF spectrum now).

People on youtube use fresnel lens as solar concentrator, you can get a lot of heat from this apparently (enough to melt just about everything).

What does your household do differently that allows your consumption to stay so low?

I'll guess : hang up clothes rather than put them in the dryer?

Not even close. An electric clothes dryer on an eco-friendly cycle typically uses about 1 kW. Older models on higher-heat cycles use up to a staggering...4 kW. And that's just for the few hours a month that it runs, it will be off for the other 720 hours.

The real difference is that OP probably lives in a well-insulated house in a moderate climate. In the hot, humid parts of the southern US, it's common to use 50 kWh/day just to keep the house liveable.

For clothes, we both hang up and use an efficient condensating drier.

We live in a (renovated) townhouse/terraced house in a moderate climate indeed, with good insulation and ventilation.

Limited always-on electric components here: fridge/freezer, internet modem, phone base station and ventilation system. No big screens. Cooking is electric though.

"Few hours a month" !! Ours runs for many hours every day.

How do we make renewables more competitive so that we can get our local utilities to invest in them?

A carbon fee and dividend. Price carbon at its true cost and let the market decide! There is important work being done by Citizen's Climate Lobby. CCL is incredibly effective, but we need the help of the creative minds and energies of HN. Check out citizensclimatelobby.org to get involved in your local chapter.

Can you buy clean energy from your utility? If you're in California PG&E has a program called Solar Choice where it attempts to offset your electrical consumption by building additional renewable capacity. So far it's only added about $2 or $3 to my bill. Many other utilities have similar programs.

At the risk of stating the obvious, if it's only added $2-3 to your bill, then it's only given the energy company $2-3 to build renewable capacity. That's not nearly enough to make any kind of meaningful impact in your carbon footprint (assuming you have somewhat average consumption).

I spend about $20-30/month on electricity, so it's about a 10% change. My electrical consumption is about as low as I think one can get it without going without things like refrigerators.

This might be controversial but I'm genuinely ignorant on the matter. How and why would you do this? Obviously I get that the "why" is because it benefits the planet. But, every nation has a stake in the planet so this seems like it would imply that it's more strategic to hold out until economically persuasive reasons are given to adopt change. Otherwise, we're putting pressure on our own organizations for free when we could instead wait for external forces to offer incentives which would be more beneficial overall. I realize that this is an unapologetically cutthroat strategy but, when most of the high confidence predictions for global warming based disaster are as far as a century out, it seems like there's a lot to lose by doing things voluntarily.

The predictions for global warming are not a century out. They are simulated up to a century out because there is no point to going further. If we are still emitting carbon in 2100, the planet will become uninhabitable.

The predictions for global warming are generally based around emissions peaking within the next five years and then declining (RCP 2.6). A peak around 2040 (RCP 4.5) results in a 3-4 C rise over the next 30-40 years causing widespread deaths[1]. The 2003 European heat wave was a +5-10 C anomaly that killed over 70,000 people; every heat wave would become that severe. Summers and winters would kill tens of thousands of people. Postponing will only lead to a weaker economy and higher death toll.

And regardless, the US is already behind almost every major country on renewable energy, including china and india. We're already playing catch-up.

[1]: https://www.greenfacts.org/en/impacts-global-warming/l-2/1.h...

Unless there's a major part I'm overlooking, your link doesn't mean that the entire planet will become uninhabitable by 2100. Nor does it imply that infrastructure accommodations couldn't mitigate the effects of global warming for nations with strong enough economies to construct them. For poor countries that can't adapt to climate change this is obviously a major loss. For nations that are wealthy enough to adapt or, at the least, soak up any losses in order to achieve an advantageous position the implication is still that they would be better of mitigating carbon emissions only when given a financial incentive. Further, while the U.S. is behind in terms of raw production, that doesn't immediately equate to a bad thing. China and India have pollution clouds. This isn't something that the U.S. has really seen at large since L.A. between the 70s and 80s. It's simply less of an issue. Catching up is only good if there's an actual benefit. Otherwise, it seems like the math would dictate that it's better to wait until other countries start offering either money or deals to incentivize reciprocation.

What? You want the US to be paid to be a decent world citizen? China and India might have pollution clouds, but if you compare their pollution per head of population to that of the US, how does the equation look? Ignoring the problem or running a protection racket is not how this gets fixed.

I've presented this from the perspective of the U.S. but I think the same position could be argued for a lot of countries. Further, India and China are doing better in terms of pollution per capita as you've pointed out. However, the counterargument would be that both natiuons' populations are the result of their own domestic policies. There's no reason for other countries that have successfully managed to restrain their own potentially explosive population growth via domestic policy to give China and India a pass because of raw numbers. If China and India are concerned about the difficulty of regulating their nations' pollution in lieu of their massive populations that shouldn't be everyone else's problem. If they want to make trade agreements based on their pollution output that's one thing. But arguing that looking at raw output is unfair because of their per capita output ignores decades of irresponsible population management on their part.

The US and Europe have not "restrained" explosive population growth; they just had it in the 19th and early 20th centuries instead of in the late 20th and early 21st centuries. The European population as a percentage of the world's population, for example, peaked around the first third of the 20th century. The UK population multiplied by 7 to 10 from 1800 to today; the German population in more or less its 1914 borders multiplied by 3 between 1834 and 1914 (I don't have a comparable census going earlier); and US population from 1790 (first census) to 1830 (when immigration became more of a factor and confuses the picture) tripled. Note that for Germany and the US I'm restricting myself to subsets of the demographic transition period; in most modern developing countries this process has been compressed into about 50 years.

See [https://en.wikipedia.org/wiki/Demographic_transition] for more on this (damned near universal) phenomenon.

That doesn't really address the core of my argument though, which was that poor policy for mitigating explosive population growth led to China and India have such wildly population sizes compared to other nations. To put this in perspective, the world has 7.5 billion people roughly, China and India account for 2.6 billion of that figure. I don't see a hard reason for why other nations should seriously consider per capita emissions a fair metric for designating responsibility when China and India gain such a strong advantage from that metric compared to similarly developed nations. It seems like there's very little reason why any nation besides China and India would consider that economically fair.

I appreciate your point that other nations have also experienced explosive population growth. However, it's hard to find that persuasive when the end result is two countries having over a third of the world's total population. Especially when neither of those countries are ones that you cited as having had their explosive growth before the rest of the world. It's difficult for to see that as something that happens with responsible domestic policy.

Yes it does. You think China having 1/6 of the world's population is just a factor of modern policy? That's probably (estimates are fairly fuzzy) lower than its proportion of the world population in 1600. See e.g. [1] which estimates world population in 1600 in a band centered at 550m, with estimated populations of late-Ming-dynasty China around 160m.

You seem to view the mid-19th to early-20th centuries, when Europe temporarily had about 1/3 of the world's population because it went into its demographic transition so early, as a good baseline. It is not.

The reason I mentioned Europe having gone into its explosive growth so early is that it was so early that it affects your assumptions, such as that Britain "should" have a quarter instead of a twentieth of the population of China.

[1] https://www.census.gov/population/international/data/worldpo...

>>If we are still emitting carbon in 2100, the planet will become uninhabitable.

Do you have any sources for this claim? From what I understand, the science does not support this claim. I've seen models predicting 200ft sea level rises, a drastic increase in deserts, and a possible failure of our current agricultural system, among other things. These are undoubtedly bad, but are far from rendering Earth "uninhabitable".

An echo from a previous comment: https://news.ycombinator.com/item?id=14710571

+1 to CCL, they are a well-respected organization.

(disclosure, I work at Google, but not in any way related to this project)

How would world trade view interpret carbon taxation. Say the US or Russia think taxing the carbon impact of products and services would lead to better climatic outcomes.

Let's say the US and Russia have assessed the costs for all gods and services and want to levy them on all products foreign and domestic. Would those taxes/levies amount to "trade barriers" or is there a loophole around that?

It isn't a trade barrier if levied evenly across all imports and doesn't discriminate against foreign producers.

There is an important omission here: battery technology. I'm not talking about tesla power walls - although they would go some way to smoothing the troughs for solar.

I'm talking about the 7.2 megawatt-hour sodium-sulfur battery systems that islands like Reunion adopt, or Japan's 34-MW, 245-MWh wind energy stabiliser.

Installing local generation systems and removing the burden on the national grid systems which lose so much energy to transmission will also have an impact that I think is not calculated here in the visualisation graph.... it can make up to 6-9% of a difference! This figure can be up to 20% in undeveloped countries.

...but I have not read the paper - maybe those effects are mentioned there

Energy storage is part of the model by default.

If you play with it here:

https://google.github.io/energystrategies

Click "Explore Future Assumptions" and you can toggle storage on and off. As expected, you can't rely solely on solar and wind when the storage toggle is off.

> Energy storage is part of the model by default.

Not quite. You can end up with a model where there's excessive power during some parts of the day and not enough power during other parts; energy storage would allow using the peaks to fill in the troughs.

If you go to the advanced page, it includes storage as a part of the calculations when optimizing for cost.

It usually doesn't play a very large part (I was only able to get it up to ~$2/mWh) but it certainly counts.

> I'm not talking about tesla power walls - although they would go some way to smoothing the troughs for solar.

Tesla has some of the largest utility scale battery storage systems in the world deployed:

http://www.businessinsider.com/tesla-powerpack-uses-2017-7/#...

I'm starting to think it's a waste of time even pursuing battery storage on a large scale. Sometimes going low-tech is the better and cheaper way.

This tech looks _way_ more promising and it's already in use now:

Molten salt storage https://www.scientificamerican.com/article/new-concentrating...

I have no idea the costs, but I'm sure if ramped up it could be cheaper.

Heliostat molten salt looks to be so promising for so many different applications. There is a looming water crisis that I think heliostat molten salt could help alleviate by using it for desalination.

I never had any faith in national grid scale batteries powering everything over night. If this is good as it sounds it looks like the future to me, being so much less limited by rare resources.

We'll probably always need electricity, so we need some solutions, but nothing compares with reducing consumption -- principally each person using less and having fewer people to use it. As in business, you don't only increase revenues to increase profitability. Often lowering costs is more effective.

Starting points include getting past the belief that happiness or society depends on electrical power as much as it does. We need some, but nowhere near what we're using.

Also accounting for costs that are currently externalized.

Any plan that depends on individual consumers making choices in the aggregate to solve the problem is simply doomed.

Hacker News seems to have interesting collective beliefs such as that it's easier to go to Mars than to turn off the lights when no one is in the room.

Smelting aluminum requires between 12,500 kWh and 15,000 kWh of electricity per ton of yield.

My lights use 8.5 Wh apiece.

The notion that consumer savings will make a dent in our problem has a few problems with decimal places. This is, by-and-large, a capital-driven problem. It's probably true that a reduction of individual consumption of stuff would be more beneficial than our energy use, too...but then that creates a new problem for that capital, too. So not only is avoiding the collective-action problem probably easier, but it's more effective, too.

1. Working on the different problems you described is not mutually exclusive.

2. How many aluminum smelting plants are there? How many light bulbs? The decimal places seem to go the other way.

This Wikipedia page -- https://en.wikipedia.org/wiki/List_of_aluminium_smelters -- lists a bunch of aluminum smelters. While it says it's incomplete, its existence implies it has most of them. I doubt there is a page listing all the light bulbs. Once habitualized, turning them off takes negligible extra time or effort.

3. I don't mean to be flippant, but are you arguing against conservation?

I do think there is something of a point there in that combined industrial and commercial use account for a larger portion of overall consumption. But, residential use is still significant.

This chart is old, but has a nice quick visualization of where you might want to focus.

https://www.epa.gov/sites/production/files/styles/large/publ...

At least showing that for residential use, upgrading your AC, refrigerator, etc is probably higher impact than focusing on lighting.

1. Agreed, but whataboutism--and you may not mean it that way but your post sure sounded like it--is basically never helpful.

2. OK. Aluminum smelters and oil refineries and frigging box factories and everything else. Start summing up. Those numbers don't show what you want them to show, I'd wager.

3. I'm arguing that it is a hell of a lot better to go after the people who actively benefit from disproportionate use because they are causing the deepest externalities.

I don't know if this adds or detracts from what your saying but here in NZ 13% of power usage is aluminium smelting. 44% is industry, 32% commercial and 24% residential. Transmission loses 6% (not sure why the above totals add up to 100%, so it must exclude the losses).

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

I did some back of the envelope calculations and if everyone on the planet runs 1.4 20W lightbulbs (100W equivalent CFL) half the time, that comes to the amount of energy expended on smelting Aluminium.

Aluminium per year: 720000GWh

20W (100W equivalent CFL) Lightbulb on half the year: 87.6KWh

Aluminium = 8.21917808 × 10e9 lightbulbs

Probably wrong in many ways, but I'll post it here anyway.

> My lights use 8.5 Wh apiece.

Then again your lights used 40-60w apiece just few years back.

Neither Mars travel nor reducing energy consumption is going to happen by the individual people magically choosing to do the right thing required for that goal. In general, our societies don't work like that, achieving such things requires coordination to create/enforce appropriate incentives for each individual.

Going to Mars requires a large organization (or a bunch of them) creating significant incentives for people to work on that goal, i.e., paying $bignum to many employees and suppliers - or it's not going to happen.

In the exact same manner, practically reducing energy consumption would require a large organization (or a bunch of them) creating significant incentives for people to reduce consumption, e.g. governments enforcing a significant carbon tax that raises the cost of electricity so much (or some other policy that brings visible, practical impact on each particular individual depending on their actions) that untold millions of people will be strongly motivated to change their habits - or it's not going happen.

What percentage of electricity consumption do you think is consumed by things like unattended lightbulbs? I'd be surprised if the numbers were at all significant in the grand scheme of things.

We have successfully sent robots to Mars, but... I don't really need that light on in the living room.

That's not true if carbon fees are used to price in the damage done by carbon. At that point the free market fairy kicks in and lets simple decisions to buy the cheaper thing do a lot of the work without the consumer needing to think too much about it

It might reduce consumption some (though not without problems of its own) but electricity is already not free.

How about encouraging each community worldwide to plant more trees, thereby offsetting their carbon usage? I know the carbon gets released when the trees die or are burned but the tree biomass overall is what matters.

Cut down the trees and use their timber for building. Then repeat (trees grow to maturity in 15-25 years in my neck of the woods).

Concrete-based construction is popular because it is easy, fast and cheap, but the hidden costs are the massive associated emissions.

Timber by contrast is harder to work with, but locks the carbon into the building, which hopefully will remain standing for many decades.

I like this idea! I mean, buildings can catch fire as well, but you can fireproof them. http://m.firefree.com/

Also if your goal is just to reduce carbon in the atmosphere you literally DO chop down trees and make sure they don't rot (timber into lumber and plywood) and the you can bury them under a sarcophagus or something.

In short, if your utility is building vs removing carbon from the atmosphere, you choose what to do.

Why don't people do this on a planet wide scale?????? What is the downside? Seems it would be an amazing natural carbon sink. What are the downsides and obstacles?

If private companies planted trees they could monetize all that timber also!!

I once did napkin math on how much forest should match carbon emissions. The number was large but it seemed very doable by a large land mass wealthy (who could that be?) state with sufficient commitment. Seriously feel like mass reforestation is under-discussed from my armchair studies.

It's not enough to plant trees, you have to trap the carbon they gather somehow. Otherwise when the tree dies, the decomposition process throws all that carbon back in the atmosphere.

The early plants (billions of years ago) went through a few generations before other organisms evolved to feed on their carcasses, so they just ended up buried deep underground, trapping their carbon (and lowering the carbon concentration in the atmosphere) until we came along and decided to dig them up and burn them, throwing all that carbon in the air again.

>...went through a few generations before other organisms evolved to feed on their carcasses,

You might be understating the time frame here a little bit. Most estimates I have read said it took about 60 million years before evolved the ability to break down lignin.

https://www.scientificamerican.com/article/mushroom-evolutio...

They do that here. The DNR sells very cheap seedlings in spring.

But where to plant them? Around here(rural Wisconsin) anything that isnt roads, houses, or farmland is trees. Trees require the same soil as food.

They could plant more in the city, which would lower air conditioning costs by providing shade. But mature trees are a safety hazard, as they can fall during storms.

I think you forgot that while Americans can and should save (a megawatthour ISN'T, or at least shouldn't be the average per month per house, vide the article), the rest of the world is way, way behind.

Are you telling Indians or Africans that they cannot even have electric cooking? Coal stoves kill thousands each year. Remember, you guys only have like 5% of the population.

You can limit your consumption -- it is grotesque -- but much of the rest of the world don't even have one lightbulb.

Interestingly, shifting off-grid users from kerosene loghting to solar powered led lamps with built in batteries is helpful for climate change too.

It's actually cheaper too, though there's an up front investment needed. Some charities are selling the devices in exchange for the weekly kerosene outlay, so that the project is self funding.

If we've built a Dyson sphere around the sun and have no more spare energy sources available in the solar system, then we can start thinking about reducing energy usage. If you cut back energy use by 50% for 1 million years and it delays this point by even 1 second, you've probably already lost out.

Until then, the energy your aunt Sally uses to run her AC pales in comparison to the amount of wasted energy being sent into space every second and so it's always worth doing research to capture that excess. There are plenty of rungs on the energy ladder before then, too:

https://en.wikipedia.org/wiki/Orders_of_magnitude_(energy)

In particular, capturing 100% of the solar energy hitting just the Earth would get you 10000x the US' electricity consumption in 2009. At those ratios, saving energy is just a bad idea compared to capturing more: If a key scientist has to spend even 1 day sorting his recycling or hunting for a more efficient AC, you may have already lost out.

If we captured 100% of solar energy wouldn't everything on Earth be dark?

You'd allocate some of it to heat and light. But the fact that solar panels are useful implies that mankind would prefer to allocate a portion of that energy differently.

"100% of Earth's inefficiently-allocated incoming solar energy" is too subjective to earn a Wikipedia entry, but I assume it's a substantial fraction of the entire "100% of Earth's incoming solar energy".

Adding more nuclear makes energy cheaper and cleaner. Add more nuclear.

Cleaner, yes (arguably). But not cheaper - nuclear is very expensive!

The Google model suggests $2200/kW is the build price point at which all carbon emissions will be displaced.

To give an idea of the cost of nuclear, the UK is currently building it's first new nuclear station since the 1990s (Hinkley Point C), at an expected cost of £20.3b ($26.3b) for 3200 MWe capacity. That's $8230/kW - almost 4x more expensive than what's needed!

Construction cost is not the real criteria that should be used to evaluate power.

>...The levelized cost of electricity (LCOE) is a measure of a power source which attempts to compare different methods of electricity generation on a consistent basis. It is an economic assessment of the average total cost to build and operate a power-generating asset over its lifetime divided by the total energy output of the asset over that lifetime. The LCOE can also be regarded as the average minimum cost at which electricity must be sold in order to break-even over the lifetime of the project.

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

According to the chart in the wikipedia article, Hinkley Point C will have a strike price of about £93 per MWH. In comparison, ground solar is 80 onshore wind is 62 and offshore wind is 102.

According to the chart in the wikipedia article, Hinkley Point C will have a strike price of about £93 per MWH. In comparison, ground solar is 80 onshore wind is 62 and offshore wind is 102.

Note that the Hinkley C strike price is set in 2012 currency and will be adjusted for inflation, so will actually be significantly higher when it goes into operation.

It can't be directly compared to wind strike prices for current projects which are priced in the year they go into operation.

Offshore wind prices are falling rapidly due to intense competition, new technology, and economies of scale. Nuclear, not so much!

http://www.telegraph.co.uk/business/2016/10/02/cut-throat-co...

To make comparisons harder, you can get usage out of a wind farm that is partially constructed. If 1 of the 500 is turning it could be generating electricity. It's hard to use a partly constructed reactor, or even coal plant.

What makes this difficult to compare is that a nuclear plant will likely have a capacity factor > 90% and wind will be < 40% and solar < 10& (in UK). The low capacity factors will add in lots of additional cost if wind or solar is expected to some day be a significant source of power.

Strike prices are in terms of the energy actually produced, so they can be compared directly.

You can, of course, argue that baseload is more valuable than intermittent sources, but also remember that nuclear doesn't scale well - that strike price will still be paid in the middle of the night when there is low/no demand for the energy its producing. (For that reason, storage will help us make more efficient use of nuclear as well as renewables)

Wind is already a very significant energy source in the UK, supplying up to 50% of all demand on the windiest days, and 11.5% of all overall demand in 2016.

>Strike prices are in terms of the energy actually produced, so they can be compared directly.

In a sense. But as I said, the low capacity factors will add in lots of additional cost if wind or solar is expected to some day be a significant source of power. For example:

>... In June 2011 several energy companies including Centrica told the government that 17 gas-fired plants costing £10 billion would be needed by 2020 to act as back-up generation for wind. However, as they would be standing idle for much of the time they would require "capacity payments" to make the investment economic, on top of the subsidies already paid for wind.

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

If by ramping up wind power the country must spend huge amounts of money for capacity payments because the plants will (hopefully) sit idle, then that cost should be added to the cost of wind. Anything is better than using coal, but people should be honest about the real costs of their choices.

>...You can, of course, argue that baseload is more valuable than intermittent sources,

Is this actually a point that anyone disagrees with? As Bill Gates said in an interview "…They have this statement that the cost of solar photovoltaic is the same as hydrocarbon’s. And that’s one of those misleadingly meaningless statements. What they mean is that at noon in Arizona, the cost of that kilowatt-hour is the same as a hydrocarbon kilowatt-hour. But it doesn’t come at night, it doesn’t come after the sun hasn’t shone, so the fact that in that one moment you reach parity, so what? The reading public, when they see things like that, they underestimate how hard this thing is. So false solutions like divestment or “Oh, it’s easy to do” hurt our ability to fix the problems. Distinguishing a real solution from a false solution is actually very complicated."

https://www.theatlantic.com/magazine/archive/2015/11/we-need...

>...but also remember that nuclear doesn't scale well - that strike price will still be paid in the middle of the night when there is low/no demand for the energy its producing.

"low/no demand"? What developed country on this planet has no demand for electricity at night? For example, in the New England area, on an average day the demand for electricity varies from about 11 to 17 GW. With the coming electrification of the vehicle fleet, I don't think electricity usage will decrease at night. In terms of grid stability, nuclear doesn't have a problem with load following, but since the fuel cost is so minimal, it is more economic to not do that.

>... (For that reason, storage will help us make more efficient use of nuclear as well as renewables)

I don't think anyone disagrees with that. (Gates is investing in 4th gen nuclear and energy storage companies so he is putting his money where his mouth is.)

>...Wind is already a very significant energy source in the UK, supplying up to 50% of all demand on the windiest days, and 11.5% of all overall demand in 2016.

50% of all demand on windy days? Do you have a citation for that? I would think that might be true for Scotland, but kind of surprising to me if it is true for the entire UK.

> In June 2011 several energy companies including Centrica told the government that 17 gas-fired plants costing £10 billion would be needed by 2020 to act as back-up generation for wind.

That was highly wishful thinking on behalf of gas plant operators. In fact, I believe only one new CCGT plant (Carrington) has been commissioned in the UK since 2010, and during this time several older plants were closed. No further gas plants are currently under construction in the UK or seem likely to be built in the near future, despite very low gas prices.

Storage technology and interconnects (including reversible interconnects such as the North Sea Link to Norway) are likely to be the better solution to intermittentcy.

> Is this actually a point that anyone disagrees with?

Baseload is an important part of the grid infrastructure, but it doesn't make sense to over-build it...

> In terms of grid stability, nuclear doesn't have a problem with load following, but since the fuel cost is so minimal, it is more economic to not do that.

Nuclear can not follow load like a gas turbine can! Sure, a few plants in France are built with the ability to scale down to 50% power or so (essential because of their high percentage of nuclear) but the vast majority around the world operate only at their full rated power.

Even when designed to ramp, it takes time to reduce and increase power in a reactor (hours rather than minutes, like in a gas turbine) and these ramps are performed to a schedule rather than in real-time response to grid demands.

> "low/no demand"? What developed country on this planet has no demand for electricity at night?

Supply can easily exceed demand at off-peak times if you have too much inflexible baseload power. Thus there would be no demand for the power produced from additional nuclear power plants at night.

It doesn't make sense to build expensive baseload just to satisfy demand peaks. There are cheaper options.

> 50% of all demand on windy days? Do you have a citation for that?

Sorry, it was 50% renewables, including solar and biomass. Source: http://www.bbc.com/news/business-40198567

We are now regularly over 50% for combined low-carbon sources, including nuclear, however.

You're looking at capital cost. The plants last a very long time and have low operating costs, so the kWh cost is fairly low.

Playing around with Google's tool without changing any defaults, I'm able to get lower carbon emissions at the same cost by setting the nuclear level to the minimum demand, compared to using lots of wind/solar and filling up all the rest with gas.

"You're looking at capital cost"

Yes, as is the Google model. They suggest that if a 24/7 carbon-free energy source could be built at a capital cost of $2200/kW, then it would displace all carbon emissions within 27 years.

My point is that capital cost of nuclear is currently far above that level, which is why little nuclear is getting built (in most of the world) today.

Also, the operating cost of nuclear is high compared to most renewables! Particularly when you account for substantial end-of-life decommissioning costs, and the cost of secure waste storage far into the future.

(The decommissioning costs for the UK's MOX reactors is close to $100 billion)

Actually it's not, the model optimizes for the minimum overall LCOE (i.e. kWh cost).

Their paper's abstract does say: "DOSCOE shows that to cost-effectively remove the last 10-20% of fossil fuels requires a moderate price on carbon and either low-cost nuclear power or carbon capture and sequestration. Alternatively, a hypothetical zero-carbon source needs to have a net present cost less than $2200/kW (with a 100% capacity factor) to displace existing fossil-fuel plants."

Actually it's not, the model optimizes for the minimum overall LCOE (i.e. kWh cost).

You're right. I meant that the Google abstract: the $2200/kW figure referring to capital cost.

Interestingly, the UK has enormous potential for tidal lagoon energy. These developers claim that it would be the cheapest energy of all new UK power projects:

http://www.tidallagoonpower.com/projects/swansea-bay/

What counts is LCOE not just build cost.

But you're right that somehow we lost ability to build nuclear power stations without going over budget several times.

Regulations: http://www.realclearenergy.org/articles/2017/08/10/the_nucle...

Comparative costs: http://www.world-nuclear.org/information-library/economic-as...

I wouldn't be surprised if nuclear is expensive solely because it's ostracized.

The moment it becomes unfashionable to bash it is the moment R&D can drive the cost down, as in every other area of technology.

A lot of nuclear power plant costs is manual construction labor. Construction costs are continuing to rise, because the fields efficiency improvements are far below the general economy.

And the moment that insane regulations are lifted.

http://www.realclearenergy.org/articles/2017/08/10/the_nucle...

What's the lifetime of the plant?

The cost to build the plant must be amortized over it's lifetime, plus the operating expenses required to operate.

I'd love to see a tool like this for comparing Internal Combustion Engines to Battery Electric Vehicles.

By some previous calculations of mine, it looked like BEVs had 10k miles worth of CO2 baked into the batteries, but I honestly have no idea if that is correct or not.

That isn't improbable - half the emissions associated with an IC-engine car stem from its manufacture[1]. Of course, the battery should be recycled, so you'd hope that in the long run those numbers will come down.

1: https://www.theguardian.com/environment/green-living-blog/20...

Lithium based rechargeables are unlikely to be recycled in the near-term. Doing so is hard, and there are a variety of chemistries used, so you don't have the economies of scale like with lead-acid, where recycling one lead-acid battery is much liker recycling another.

I always see comparisons for gas consumption vs construction of electric vehicles but they never include the CO2 emissions related to producing ICEs and transmissions.

Seems about right:

"Over the vehicle’s lifetime, however, the global warming emissions benefits of driving on electricity far outweigh the emissions costs of vehicle manufacturing; most EVs “pay back” their production emissions within one or two years of driving, a period that will shorten as electricity grids get cleaner.

Read more about manufacturing emissions in our in-depth analysis of life cycle EV emissions, "Cleaner from Cradle to Grave" (2015)."

http://www.ucsusa.org/clean-vehicles/electric-vehicles/ev-em...

(They also have an interactive tool, but it only does mileage based on your local grid and vehicle, not manufacturing)

That was always my argument. I think that to look at it holistically, you also have to consider people who are adding an EV instead of replacing a normal car with one. Rich people love tax breaks, and they're happy to drive a Tesla with $7k paid for by taxpayers. If you do replace a car, factoring in not just the EV but the effects of that otherwise-serviceable car being scrapped or whatever. Consider also that EVs becoming popular creates more demand in general for cars, so someone is likely to purchase a new EV when they could have just kept using their normal car.

The study is interesting but actual deployment of any strategy is still out of Google's control, so I fear this tool will live as little more than an academic exercise, same as similar tools coming from academia, supernational organizations and biased lobbies. That said, Google is also actively investing in electricity generation and that kind of effort may come more useful, if pursued with determination, so we will see where they actually put their money, other than their mouth.

These tools are really compelling to me. I was dubious that a carbon tax would be sufficient to motivate substantial change, but it looks to me like a $40/ton carbon tax would drastically improve carbon emissions, and a $100/ton tax would virtually eliminate it.

I think as a way of exploring regulatory goals they're fascinating - very few situations does someone set up a simulation of the impact of a law and give laypeople knobs and buttons to play with to see how it would work.

It's something I thought about creating too, but it seems to miss a lot of variables, solar and wind is not constant during a year so it should be yearly not weekly, it seems USA specific it should be able to take solar or wind data per country there is massive variation of rate depending on the region, also consumption is geographic dependant.

And it crashes on my iPad after few seconds.

Fundamental problem : Electricity is not sufficiently costly to induce people to figure out how to consume less.

(Oh Googleers and your vast screens. I can't get both the controls and the readout in the same screen. :-( )

One thing that people should look at is MOF or other solutions to do carbon capture at existing fossil fuel/coal plants. MOFs can be highly efficient at removing carbon output from these older plants.

Then the flue gases we currently emit can be re-used as reagents in algae bioreactors to produce biodiesel.

Google could invest a bit more money in R&D. They sit on awesome pile of money and yet aren't a significant player in energy. Why? Not smart enough? Don't think so.

Oh, i forgot. Google is here to make money. They might write some blog posts about CO2, but will not use their leverage to change things. That would damage the bottom line.

Why is it that all the big companies are 100% driven by short term profits? Maybe our understanding of capitalism isn't so great after all. We need more responsibility.

Google has no competitive advantage in energy. No way to evaluate world class expertise. If I plowed a billion dollars into energy, I'd waste most of it, and they wouldn't do much better.

You'd waste it only in comparison with some hypothetical others spending a billion dollars in a hypothetical zero sum game where either they or you spend that, but not compared to not spending it at all or on stuff that makes the problem worse.

Now if we could only find a solution to the difficult problem of massively powerful tech companies prying into our lives and selling what they discover for profit..

Oh, Hi Google!

Does nuclear power also add heat to the Earth?

All forms of obtaining energy for use in machines have heat as a byproduct.

How long can we sustain that?

Earth's heat is in an equilibrium with the Sun and Space. If you add a heat generator, you will see that more heat is emitted out into space and the temperature does not increase much (and stays constant after a short increase). But if you change the equilibrium point (like by adding greenhouse gases), you'll see the temperature changing quite quickly.

How do the greenhouse gases change the equilibrium point while other mechanisms of increasing heat don't?

Greenhouse gases don't simply increase heat. They change the composition of the atmosphere. It's similar to the way adding salt or alcohol to water will change the freezing temperature of the water.

Greenhouse gases don't add heat, they reduce the amount radiated to space, thus making the planet warmer.

Technically both change the equilibrium point. But one acts by adding heat, and the other by directly influencing the equilibrium.

Yes, but it's an extremely low amount compared to the heat we trap by emitting greenhouse gases.

Solar panels also add heat to the Earth, since they are black and absorb more solar radiation than a lighter-colored surface. This is also extremely minor compared to fossil emissions.

Setting the carbon tax level to the EPA's social cost of carbon seems to work out.

The carbon tax especially works out for the political class & bankers who would be entrusted to manage the funds & transfer the wealth. It also benefits the wealthy Tesla buying consumers at the expense of the poorer gasoline buying public. In the meantime, Al Gore has multiple houses & uses 34x more electricity than the average US household...

http://dailycaller.com/2017/08/02/exclusive-al-gores-home-de...

Also, don't plants breathe carbon? Wouldn't this imply that there would be a biological feedback loop (more carbon means more plant growth)?

Not to be confused with decarbonating electricity.

edit aw https://news.ycombinator.com/item?id=14986447

Electricity doesn't usually have carbon in it. It's more convenient to push electrons back and forth in a wire than it is to push carbon atoms back and forth.

Reply on news.ycombinator.com