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Comment by nostrademons | Hacker News Reader

It's interesting how renewables have suddenly made time-of-day critical in energy consumption.

IMHO, not enough attention has been paid to how important better insulation + workplace EV charging are to the energy transition. If homes were insulated like they are in Northern Europe (where you can go a week without heat and your home will still be tolerable when you get home) rather than Northern California (where your furnace cycles on after an hour despite it being 55F out), you could run basically all residential HVAC during daylight hours, when solar is producing abundantly, and turn the housing stock into a giant thermal battery. And similarly, if everybody charged at work rather than at night, you power transportation on solar rather than on natural gas.

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If consumers paid close to wholesale rates for their home energy they would be highly incentivized to do these sorts of things: they'd pay almost nothing (or maybe even less than nothing) in the day and big bucks from 5 PM to 8 PM. There would be whole industries helping people shift consumption to daylight hours. Unfortunately legislatures have consistently been acting to shield consumers from variable time of day costs, preventing behavior adjustment.

Well yeah because most people are away from home during those hours so there's little you can do. And workplaces, schools like that working hours are when electricity is cheap.

Workers might start demanding WFH or that their leisure hours be during the day and we can't have that.

The point is to enable markets for the technologies (many existing today!) that would let you time-shift effectively. Smart lights and smart thermostats are nifty gimmicks today; if electricity cost 100x more at primetime, they'd become critical investments. Insulating and air-sealing your home is known technology, but often not cost-effective when you can just burn a little more natural gas. Workplace charging is a perk, not a deciding factor for where people choose to accept a job. If the consequences of people's decisions were priced into the cost of them, people might make different decisions.

I'm not sure smart things and sealing would be the go-to solution when we're talking 100x the cost. Even 10x the cost starts to make the electricity bill close to rent. Whole house batteries, gas/pellet heaters, and gas stoves would suddenly get a lot more popular.

I'm not sure "throw out your major appliances that run on electricity and don't even look at plug-in EVs" is the direction we want to go when being able to cheaply meet evening demand at the grid level with renewables is the eventual goal.

The 100x comes from it being way cheaper during off-peak, not way more expensive during peak. You see the wholesale rates on this site; they're negative or a few cents/kwh at most. If that price differential were translated to retail we'd see rates of ~1c/kwh off-peak and ~$1/kwh peak, which is a pretty strong reason to charge your EV off-peak.

Yeah this is all a thing in the UK where there’s a lot of highly variable Solar & Wind electricity generation, see https://octopus.energy/smart/intelligent-octopus-go/

Disclaimer: I work for Octopus Energy Group.

I don't understand why the government don't do more to support these kind of tariffs that incentive demand shifting.. it seems such a powerful way to make the grid greener without huge infrastructure projects

They're very unpopular with consumers, who are allergic to price increases and particularly to variable price increases. Look at the blowback to Wendy's surge pricing on burgers, or to Uber surge pricing, or to toilet paper scalpers in COVID, or to any notion that you might lose your job and need to retrain in a different one in response to changes in the economy.

The last thing a politician wants to do is lose an election, and losing an election is usually what happens when you suggest that the electorate bear the consequences of their behavior. As a result, we usually drive straight off a cliff, have a war or societal collapse, and then whoever survives it can go build a new system out of the rubble.

Make it optional and give a small subsidy to encourage people to switch to variable pricing

The most common rate plan in California (at least with PGE) is a time of use plan.

While the daytime rates are less expensive than the evening peak rates, both are very expensive compared to just about anywhere else.

It's nowhere near the price differential that wholesale is, though. Last I checked, PG&E charged 62c/kwh at peak, and 52c/kwh off-peak. Back in 2020 it was 29c/kwh peak and 22c/kwh off-peak. That's roughly a 25% difference, but the actual wholesale price is off by several factors.

In comparison, Ontario Canada has a 3c off-peak / 29c peak plan.

Holy shit. Here in Maryland we’re at $0.17 fixed and I thought that was crazy high.

There are gobs of fascinating battery ideas like this! Pumping water uphill, heating up enormous piles of insulated carbon, spinning monstrous flywheels, etc. Their plausibility is highly dependent on the environment. So I hope that we'll eventually have a constellation of these wild batteries supplying the world's storage needs. I suspect that we'll see the idea you described gain more adoption. The result: fleets of "air battery" homes climate controlled by municipalities via opt-in smart thermostats (and credit incentives) to ease grid loads.

At a previous job I helped build a hyper local method of computing spot prices to enable lots of cool ideas. We could compute unbalanced prices on the distribution grid and had a pilot project where DERs were priced based on how the influenced the local distribution grid.

For example, placing solar downstream of a transformer nearly at capacity could allow for deferral of capital upgrades that would only be needed for a few hours a day.

> It's interesting how renewables have suddenly made time-of-day critical in energy consumption.

I remember people being upset about potential time of use meters around 2000. Of course then we wanted to move consumption away from daytime when peak loads were higher than supply. Now we want to move consumption towards daytime when peak supply is higher than demand.

Nuclear had similar impacts decades ago, with "excess" energy at night.

Similar responses happened then, including night storage heaters, variable tariffs and pumped hydro storage.

This is the way...

I have solar, a powerwall battery, a high efficiency heat pump, and... a poorly insulated 70-year old home in Silicon Valley.

It can be wildly expensive to properly mitigate poor insulation: you need good air sealing, insulation around the entire building envelope, double or triple paned windows, and a different HVAC setup with dedicated fresh air ventilation. In other words, it requires a major remodel in some cases. Homes need to be built with energy efficiency as a top concern, and I wonder sometimes if that is going to require re-training and incentivizing the entire construction industry. Fewer than 1 in 10 contractors I talked to even knew what I was talking about when I asked for how they would do my project. "What's an ERV?" is a common question I heard. Many still think that gaps are good because "a house needs to breathe."

I have a 60 year old home and have made a huge dent in my winter therms and summer AC usage by simply adding some roof insulation and double-layer windows/sliding doors a few years ago.

Perfect is the enemy of good enough. You are not going to eliminate all gaps.

It currently shows that renewables are generating 145% of the total load. So what happens to the excess that isn't being used? Does it charge batteries to be used when the sun isn't shining and the wind isn't blowing? Is it exported to other states in real time? What happens to the excess energy that's generated by renewables during the day?

Batteries and interconnect exports.

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