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Comment by moh_maya | Hacker News Reader

I don't know if fossil fuels, especially natural gas, will be substantially replaced from the energy mix till we figure out massive high density power storage mechanisms at scale.

Fossil fuels provide base load power that, without storage, we simply cannot rely on most renewables to directly substitute. The only alternative has been, and likely will continue to be, nuclear power, which has its own set of challenges.

If you accept this contention, then the big driver / trigger / marker for the "end of fossil fuels as bulk power sources" is the development and at scale deployment of power storage. And I don't see compelling evidence that is happening anytime soon.

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A way to reduce base load power requirements is to raise the rates for it. A lot of power requirements can be time shifted, as a residence is inherently a large battery.

For example, the electric hot water heater. It can run when power is cheap, and not when it is expensive. The water will stay hot for a couple days (I know this from experience with power failures).

The same goes for heating/cooling the house. When power is cheap, heat/cool to the edge of the comfort zone. When power is expensive (i.e. base rate) let it drift to the other extreme. Houses have a great deal of thermal mass (again I know this from power outages) and this can be increased by using a pile of rocks as a thermal "battery".

In order to motivate people to use this method, raise the cost of the night rate.

Edit: of course, the more water in the hot water tank, and the more rocks in the hot/cold pile, the better this works. Fortunately, water and rocks are cheap.

> A way to reduce base load power requirements is to raise the rates for it.

You are heading straight to a civil war.

> A lot of power requirements can be time shifted, as a residence is inherently a large battery.

Go tell this to people living through Canadian winter with sub-zero temperature...

> You are heading straight to a civil war.

Just reduce the daytime rates. Besides, it doesn't make sense to have fixed electric rates 24/7 when the cost to supply it varies dramatically. Look at gasoline pump prices, they very all the time due to supply+demand and nobody is fighting a war over that.

> Go tell this to people living through Canadian winter with sub-zero temperature.

I agree that any solution that doesn't cover 100% of use cases is quite useless and inapplicable for the 98% of the population where it would work.

Besides, I live in Seattle which is next to Canada, and this solution would work fine in the PNW climate, which includes Vancouver B.C.

> it doesn't make sense to have fixed electric rates 24/7

Electricity is the least popular form of heating in Canada, by far, dwelling are heated with gas furnace. This, and my supply prices are contractually locked for the next 5 years regardless of the actual market price.

> Besides, I live in Seattle which is next to Canada, and this solution would work fine in the PNW climate, which includes Vancouver B.C.

Come on, Seattle/lower mainland look like the tropics compared to the rest of Canada.

Most of the Canadian population is within 30 miles of the US border or something like that.

Because the weather in Seattle is just like the weather in Calgary... or even Toronto !

Average temp in Toronto is 46.6 degrees Farenheit. It's 52 degrees in Seattle.

Source: google

... and there is a 2deg C average global temperature between the last ice age and now. Averages are irrelevant. Seattle has more constant temperature, whereas Toronto tends to min-max, and on top of that, you took the southernest Canadian city.

But sure, continue thinking Canadian weather is the same as Seattle...

If Canadian houses are any good, they are well enough insulated that they work fine with the heat-battery mental model.

Where I live, our local electricity distributor (Orion, Christchurch NZ) controls hot water heating using a short pulse-train signal transmitted over power lines. At home, a relay device colocated with our electricity meter picks up the signal, and energizes our hot water cylinder's circuit at 9pm, when our night-rate tariff kicks in. Another pulse is sent at 7am instructing the cylinder's circuit to turn off. The distributor also shuts off the hot water for one hour during the night, spreading this out over ten or so load blocks in their network. Not only does this result in load shifted to night when it is cheaper, it also means the load profile across the whole South Island is beautifully flat. This technology is comparatively ancient, and we call it simply "ripple control". My wife and I shower at night and we find we have all the hot water we could possibly need.

That's good. A more modern solution would be to simply hook the heater up to the internet.

> load shifted to night when it is cheaper

Interesting how I never see these solutions when cheap grid solar power is available :-/

This is already being done in some places. Where I live the electric company offers a plan that charges different rates based on time. 7pm to 7am is super cheap and 3pm to 7pm is super expensive. 7am to 3pm is just kind of expensive. The plan assumes you have a smart thermostat that, during hot summer days, the company can use to turn off your air conditioning temporarily, which they reimburse you for. I signed up and try to do the laundry and dish washer at the off times.

> 7pm to 7am is super cheap

This is kinda backwards if the idea is cheap solar power and expensive nighttime base load.

But anyhow, even minute-by-minute pricing can do a lot to adapt the demand to the shifting price of providing it. I never see this mentioned in a discussion on the problems of grid storage, so I bring it up all the time.

I'm in Michigan, a manufacturing state. The reason for the timing is all the factories at full capacity from 7am to 7pm.

The challenge of the storage issue has imho been massively overblown.

Years ago it was common to say "renewables can never work, they're too expensive and can at best power something like 4% of the grid". That argument clearly no longer works. Now it's turned to "but storage is too expensive".

I think the reason we haven't seen storage at scale is that we haven't needed it that much. There are very few countries with high enough shares of fluctiating renewables to need storage at scale. The ones that exist can still balance it out by exchanging electricity with their neighbors.

I'm very confident once renewables hit > 50% in a larger number of countries we'll see a development with storage similar to that of solar and wind before: Once there's sufficient demand prices for the tech will go down rapidly.

Germany had 46% renewables on average in 2019. Storage becomes only a large concern, if the renewables can achieve more than 100% of the grid load at significant times. Until then, it is more important, that the conventional power plants can be regulated quickly enough - that means gas is much better than coal as complementing renewables.

There's a massive chicken/egg problem with storage: without storage nobody will build more renewables than can be routinely absorbed by the grid and without that oversupply there's no economical incentive to build storage.

I think it might be best to feign defeat on finding a clever integrated solution and stubbornly make all the building blocks of power-to-gas profitable independently (through regulation, obviously).

The article says:

"Closer to home, Los Angeles’ utility commission recently approved a new solar plant that will deliver 300 megawatts of energy at 3.962¢/kWh (by comparison, electric power from natural gas usually costs about 8¢/kWh in the US). Importantly, that price tag includes energy storage as well, meaning the plant will be able to deliver energy to LA residents day and night."

An LA Times article [1] on the solar power plant suggests it can supply 6-7% of LA's annual electricity needs and deliver upto 4 hours of power each night.

I don't read that as 100% of LA's night time power requirements each night for 4 hours though; rather, that it can continue supplying at a steady rate 4 hours after Sun down. It's not nearly a replacement for base load power.

[1] https://www.latimes.com/environment/story/2019-09-10/ladwp-v...

Deployment is accelerating:

https://www.eia.gov/todayinenergy/detail.php?id=40072

It's likely that those deployments are matched to the better opportunities, but there are other signals out there, like investment in large fossil fuel generation plants starting to decrease.

If faced with the choice of reducing energy usage or driving global warming to the worst case scenario, are you sure we'll choose the worse option?

What does “high density power storage mechanisms at scale” look like?

The overnight storage requirements work out as adding a few cm thickness of LiIon batteries to every solar panel. Production of batteries is growing fast — eyeballing the images I’d even say exponentially, which is fast enough soon enough even if it isn’t a big enough number now.

Solar production is pretty much nil in northern latitude due to the snow pack. On top of that, my dwelling is constantly in the shade for 3 months, so panels ain't gonna help.

That’s an irrelevant point, for the same reason it’s irrelevant that a nuclear reactor doesn’t fit in your basement: electricity can be transmitted over large distances by high voltage wires. Conveniently, many of these wires already exist. Rooftop solar helps where it works, but it’s not required in any case.

Utility scale solar is typically installed on the ground where snow can easily be shoveled off. Also you can buy snow removal tools that attach to long poles for rooftop removal.

Not actually the case, as much as you'd think. Have a look at this map that covers Canada: https://energyhub.org/efficiency/

A mix of things.

There are storage options which fit different criteria. Some are very responsive to changes in demand (supercapacitors, inertial flywheel storage), but have high costs, bad wear characteristics, and low total capacity.

Some are responsive and immensely efficient (high energy-in:energy-out ratios), such as pumped hydro, but suffer from siting and environmental restrictions.

Some are slow and inefficient but scale wonderfully. Thermal energy storage, either for direct heating or for generation, is a case in point. District thermal energy storage has been used for residential & commercial space. Molten salt thermal storage can bank heat for weeks, but suffers Carnot efficiency losses of about 70%. It's cheap, simple, and non-toxic (though will sting if it gets out).

Compressed air energy storage is a lot like pumped-hydro, though it might possibly scale better and be suited to use in exhausted natural gas reservoirs. Here a problem is physics and Boyle's Law: compressed gasses heat, expanding gasses cool. This means either that you're losing a lot of energy to the environent and freezing your regeneration equipment, having to deal with high temperatures in storage (the possibility of triggering explosions in spent-gas reservoirs might be a risk), or have to re-heat expanding gas to prevent freezing in turbines.

Fuel synthesis -- hydrogen, natural gas, or liquid hydrocarbon analogues -- is an option which provides very-long-term storage capacity (proven to 100s of millions of years), but is inefficient (about 15% round-trip), and has proved uneconomic or impractable to date, despite over 50 years of research. I hold out some hopes for this.

Load shifting, and moving to a model of dispatchable demand rather than dispatchable supply might also apply.

Battery storage is another option, and will likely see some use. It's expensive, is limited by chemistry, and most of the options suffer from considerable side effects or risks. Some of the more interesting alternatives I've seen, liquid metal and molten salt batteries, both reasonably well-suited for large, static, grid-scale infrasturcture, have proved highly problematic. See Donald Sadoway's start-up, Ambri, pursuing a liqud-metal design touted loudly a few years earlier: https://www.greentechmedia.com/articles/read/ambri-is-still-...

LiON is proven, but its light weight makes it favourable for mobile and transport applications. There's a limited amount of lithium that's readily available, and reserving that preferentially for where it's best suited is probably wise.

Among the problematic aspects of batteries: electrolyte scarcity, toxicity (lead-acid, etc.), high-temperature designs (liquid metal / molten salt), reactivity, fire/explosion hazards, and fundamental energy-density limitations, are all constraints.

My read is that all sides of the power equation will change markedly over coming decades: supply, demand, transmission, storage. We've been spoilt in ways we don't yet appreciate.

Sodium ion batteries working out is probably more likely than not.

Just look to Europe for that. A lot of investments into hydrogen for storage and as a fuel.

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