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This is a great list, I’m glad to see someone promoting insulation, it’s not a sexy technology, like roof top solar or EVs, but it’s super necessary. I would add three things.

7. Set up virtual power plant policies, give property owners incentives to install storage for grid stabilization, this will enable demand shifting and reduce the need for distribution grid upgrades and enable more distributed energy sources to be installed at the neighborhood level.

8. Inter-regional transmission line upgrades. Build out transmission lines between regions. The sun may not always be shining, and the wind may not always blow. But the sun will always be shining somewhere and the wind will be blowing somewhere. This will let regions support each other.

9. Pass enabling legislation/regulation for community choice aggregation in all states. This will speed up adoption of renewables by leveraging climate action plans at the municipal level to procure more renewables and lead to the early retirement of fossil generation facilities.

To your 7. While I like it personally, it'd be more efficient if power companies put batteries at substations to absorb excess customer production. That'd have all the benefits of a virtual power plant plus the ability for the power company to schedule disconnects that don't impact customers. They also don't have to deal with lost capacity because a customer decides to disconnect before a storm (or whatever reason). It makes capacity planning easier.

>energy already stored in the car's battery can power home electronics at night.

Will those extra charging cycles shorten the lifetime of my EV? It's one thing to have household batteries, which can be replaced on their own and which are still pretty useful at 40% of their original capacity. But I can't economically replace just the battery on my EV (it'll cost more than the car is worth) and diminished range would really reduce the utility I get from the vehicle it powers.

(But thanks for getting me thinking with that list, regardless.)

Not realistically.

EV batteries are anywhere from 40->120kWh in capacity. The average home consumed consumes around 20 to 30kWh a day. Assuming you pair your EV with a solar you aren't likely using a significant portion of the battery throughout the night.

This does depend on the chemistry. If your EV is using LFPs, you have about 10k cycles to play with. NMC has about 1000.

So, for an LFP vehicle it's practically a no brainer.

> it's replacing coal not because of subsidies or policy, but just because it's cheaper.

Well, it's also being heavily subsidized, but not by the US. China has been leading the way there, and for a clear geostrategic reason: they have no access to natural gas or oil, and have to trade for it. If you want a "fortress economy" that can endure sanctions like the Russians have done, this is a weakness that must be addressed, and solar isn't a bad option.

Of course, that only works if you can physically defend them (China probably can). Humanitarian groups in Palestine tried solar, and Israel bombed the solar fields. Fossil fuel generators and their fuel stores are much easier to hide.

This post shows a good and economical path towards short term storage, on the order of hours to days. The cost of storage based on a daily charge/discharge cycle is about $100/MWh ($0.10 per kWh), which is fine if power is essentially during day time.

However, seasonal storage is a completely different beast. In the winter there are months without a lot of solar. For my solar panels, total energy generated in December is are about 15% of that in June.

Seasonal storage is a lot more expensive than daily storage, because you can use your battery for only 30 cycles (30 years) rather than 1000-5000, depending on the technology used. That means that storing power generated in June and using it in December costs somewhere around 1$\kWh, simply to expensive. Do you have any ideas on how to solve that problem?

- Move as much load out of the low-solar areas as possible. Don't put steel mills and other industrial stuff there. Do that industry in the desert where possible. Society will have to change, at least a little, to switch to renewable energy sources and off of carbon for good.

- Use 100 hour battery tech, which is almost (years not decades) at commercialization. This can bridge pretty big gaps.

- Dam and fill some big valleys in the low-solar areas with water and put generation and pumps on them, to store water all summer for winter use in generation.

- Wind works most of the year. Offshore is great for that.

- HVDC lines streching from sea to shining sea.

- The BIG one: You can save 30% or more on HVAC and other specific loads, if you let software control them better. The problem is retrofitting shitty old buildings with electronics to do it, and getting building managers to repair their HVAC systems instead of letting them languish.

The seasonal problem is all about transmission lines and counterseasonal generation sources like (pumped?) hydro. There's no way you can store up a winter's worth of energy needs in batteries. Energy storage is the integral over time of power consumption, so time-shifting demand from January to July is about 750x more expensive than time-shifting it from 6 PM to noon.

Instead, we need to rely on the fact that it's not winter everywhere, at least to the same degree. My house has a similar seasonal profile to yours, but an industrial plant in the Mojave desert does not get shaded by hillsides, does not have atmospheric rivers come in, can move the panels to follow the sun's angle, is at a far more southern latitude, etc. And several generation technologies like hydro and wind actually produce more in the winter than the summer, because rainy and windy days benefit them.

This is probably the biggest argument I've seen for the continued existence of the grid. My home can run indefinitely on self-supplied energy during the summer, but I still need the grid to get through the winter.

>Subsidize...Subsidize...Subsidize...

There's a lot to be said for market pricing and letting smart startups find an optimum solution rather than politicians picking things to subsidise which is how you end up with corn subsidies and the like.

In this case for economic efficiency you need really a carbon tax, rather than subsidise this that or the other which may well be out of date by the time the politicians are done arguing.

At least if you actually want to reduce global co2 emissions that's the kind of stuff to do though you need global buy in. At the moment a lot of the actions are more feel good greenwashing and as a result global co2 emissions continue merrily upwards.

> Subsidize workplace EV charging, and create a standard that lets workplaces pass along energy costs from it to employees.

I've never even managed to get my workplaces to provide a parking spot, you can absolutely forget about workplaces paying for EV charging for everyone. It'll never happen even with heavy subsidy.

It only took a few months to get an employer to have them installed. Financial services, a few billion in annual revenue. ChargePoint chargers. Total spend was under $50k and employee time for procurement and integration with HR information system in order to onboard employees (as they’re private and can only be used to charge by employees in a private parking facility). I provided one of my EVs for commissioning and testing.

Can totally be done. Asking is free, and if you don’t ask, the answer is always no.

Of course not -all- businesses will provide EV charging to -all- employees. Tests not a realistic goal.

But lots of businesses do provide parking spaces. If your space is reserved for you, and you drive an EV, it becomes an obvious feature to add though at minimal cost.

Clearly some will do this, its likely many already do, and if you becomes a trend then it will move the needle. Not enough by itself, but a fair bit.

This works, but it requires a lot of complexity, consumer buy-in, the willingness to add extra charge cycles (and degradation) to vehicle batteries, etc.

It’s easier to add a bunch of grid-scale storage, but more expensive.

I think both solutions will scale alongside solar/wind adoption.

My biggest problem with solar and storage is not day/week energy management we can solve that easy, add more batteries, pumped hydro, use car batteries, incentivize customers to use electricity when sun is up... All easy problem compared to seasonal storage.

Where do we get enough renewable electricity on cloudy week in December? Synthetic gas/oil produced in summer? Anything more promising?

For one thing, we could overbuild (cheap) solar. A big portion of summer solar production might be curtailed... and that might be okay.

There are a few technologies on the horizon. Using excess energy during the summer to produce a fuel, like you said, is one option. Hydrogen has been considered, but storing it long term is difficult. Another option is ammonia, although it’s toxic and corrosive, and although it produces no CO2 when burned, it still produces NOx, a potent greenhouse gas.

There are technologies on the horizon that could fill the long term storage needs for winter power. Lithium Ion, although great for mobile technologies, is not ideal for grid scale storage. It can’t store power for long. But other chemistries such as vanadium flow batteries and iron air batteries can discharge longer, and they can store power for far longer.

Use energy with atmospheric 3(C02) + 8(H20) -> C3H8 + 7(O2)

> Subsidize heat pumps, to make all heating/cooling electric.

Are there ways to try to ensure much of these subsidies end up reducing the price (and associated hurdle) of consumers rather than 80+% ending up as increased profits for HVAC companies?

Yes, competition.

That’s the general answer, and I agree with it.

I think it doesn’t work well in practice for a regulated/licensed trade (with enforced minimum apprenticeship times) when trying to do a temporary lump of conversion work (retiring working fuel boilers and replacing with heat pumps faster than would otherwise happen naturally).

As a mechanical engineer and hard-core DIYer, I can’t legally do it myself, nor get the local rebates if I do a pirate install, nor start a company to compete against the HVAC incumbents without hiring from the same limited pool of licensed HVAC techs those companies have.

Competition might work as an answer over a long period of time (with stable incentive programs).

Competition

> Invest in smart grid-aware EV & home battery charging technologies. Instead of charging whenever you first plug them in (which is usually ~6 PM), load from EV charging should be distributed to whenever the grid has excess power available, with a random factor so that not all EVs charge at once.

Within a handful of years, major home electricity-consuming appliances will come with built-in batteries used for both backup purposes but also for shifting load to the cleanest/cheapest electricity available. By this time commercial/industrial will have already transitioned to this.

I doubt that. Putting batteries into appliances sounds extremely awkward.

Apparently it has already happened https://www.washingtonpost.com/climate-environment/2023/03/2... TL/DR: batteries are cheaper than paying an electrical to upgrade a 120 line to 240.

That's a very different motivation, though. Any other reason lets you centralize your backup power. And even then, "no major manufacturers".

The simple and realistic answer is obviously nuclear + renewables. Nuclear isn’t generally easy to ramp up and down but newer models are more flexible and night time drop off in solar is predictable.

It seems to me that that depends on which problem you're solving.

(1) No power from renewables overnight? Sure, nuclear works

(2) (Planning for the eventuality where) Entire grid's demand is available from renewables during parts of the day? Either don't use the renewables, and keep the nuclear running, OR battery storage.

A decade ago I think (1) was the primary topic of armchair discussion, but (2) has become increasingly more common. It really doesn't feel like nuclear is demonstrating the ability to keep up (maybe in China though...); it's not getting built fast enough, and I don't recall the more modern designs that are in the permitting process/starting to build (in the US) toting highly variable power generation as a added capability.

I do pay less attention to the nuclear news since I finished my masters a decade ago and never worked nuclear after, so I could be unaware of some things.

One of the key stories for ev adoption though is that you can charge overnight at lower electric rates to save on gas, so we still need a clean baseload power supply for overnight.

With continued solar adoption, "off-peak" will shift from "overnight" to "midday", at least if the utilities are properly passing along their costs. I think it might already have in California - I saw someone in r/electricvehicles saying that they get a cheaper rate for daytime charging. The idea that overnight has the cheapest electricity rates is an artifact of the fossil-fuel-dominated electric grid economics, and (physically speaking) there's no reason for it to hold true with renewables.

Yeah this. Several countries in Europe have seen negative electricity prices during the day this past spring and summer because of abundant solar and wind production: Netherlands, Denmark, Finland, Portugal to name just a few.

If you had a variable electric contract (rare but possible), you were paid to use electricity during those hours. Got a battery at home? You can be paid to charge it during the day, and paid again to discharge it at night.

The idea of a decentralized storage grid sounds really cool. Instead of only relying on large centralized batteries, power companies would effectively rent capacity from their customers.

Imagine software that could run on EVs, Powerwall-type batteries, computers/tablets/smartphones, and so on, which would automatically charge and discharge for passive income. Essentially algorithmic trading, but with power instead of stock. You'd just have to configure any necessary time ranges and charge percentages, e.g. maybe your EV needs to be at 25% by 8am and again by 5pm on weekdays in order to make your daily commute.

Maybe some EVs will start to come with built-in crypto miners to burn negatively priced power when the battery is at capacity. Maybe Lyft/Uber and Waymo/Cruise will take advantage of it by increasing and lowering rates based on the price of power (if they don't already).

I think we’re likely a few years away from a tipping point beyond which adoption of powerwall style home batteries takes off in a big way. Assuming that dynamically priced electricity becomes more common, which seems inevitable.

Tesla has implemented a virtual power plant in California using people's Tesla PowerWall batteries: https://www.tesla.com/support/energy/virtual-power-plant/pge

In San Jose for me (as of last year) off-peak was midnight - 3pm.

My plan (in California) already has a super-off-peak from 8am to 4pm. Those do tend to be hours people aren't home though.

Or update price signals, to disincentive overnight charging. ...Assuming people have easy access to daytime charging.

How about using excess peak solar time to produce hydrogen?

Whenever I read about hydrogen power, there’s this sort of elephant in the room that producing it burns power, which is usually assumed to mean burning fossil fuels.

If we have excess solar during the daytime, couldn’t that be spent refining water to hydrogen and sticking that in a battery of sorts?

I feel like that would be especially useful for renewable flight and ocean travel, where the weight of actual batteries makes electric unviable.

Electrolysis is about 20% effective. That's why you don't really see hydrogen being seriously considered for grid backup.

Mass produced hydrogen comes from fossil fuels.

That said, I agree hydrogen might have a role in shipping and flight. Just not grid storage. LFPs and sodium chemistry are both cheap with a long life. That's what will more commonly be deployed.

I’m on a TOU plan that makes energy from 5-9 4 times as expensive. Which means I charge my car, heat my water, and even heat/cool my house outside of 5-9. All you need to do is offer incentives and it’ll happen.

It should be noted that the US grid spans 3 time zones. Thus significant solar power can still be generated at 10pm EST. In summer.

4. Eastern, Central, Mountain and Pacific (and some odd areas).

Ok, forgive my incorrect wording. I meant it spans 3 hours coast to coast. You are correct, there ate more than 3 time zones in that.

Details matter. Thanks for the correction.

Smartgrid has been in the works for decades. I saw it the subject of debate at conferences in 2004. There are fundimental issues, cultural issues. All those batteries in EVs are not an option. People with EVs simply do not want to discharge them back onto the grid. Firstly, they want to have their car fully charged if they need it unexpectedly. Secondly, they will not accept the diminished battery life associated with extra chrage/discharge cycles.

If we need distributed batteries, dont look to the lightweight and highly specialized batteries of EVs. Oldschool lead acid batteries are far cheaper, last longer, and are easily recycled. That is the way to build out a distributed battery grid.

Surely existing methods of energy storage methods e.g. pumping water to higher altitude reservoirs to be used for hydro at peak hours will be more useful than millions of lead acid batteries

Pumped hydro cannot be done locally. Not everyone lives on a hillside and owns a lake. For something to be distributed, placed close to end users, it has to fit in a typical garage or basement.

Much of the country is too flat for pumped hydroelectric storage to be practical. How could that work in a place like Miami or Chicago?

> Secondly, they will not accept the diminished battery life associated with extra [charge]/discharge cycles.

For the correct price, a great many would. Once the batteries are too degraded for mobility use, they’re still often usable for fixed storage.