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Comment by mrfusion | Hacker News Reader

I hate the argument that we’re just waiting for batteries now.

I think if we had variable pricing that matched the availability of renewables, consumers would shift quickly.

Say something like power costs .02/kWh while the sun is shining and .30 when it’s not.

I’d charge my car at work. I’d put a timer on my dryer to turn on at 10am. They probably come out with a hot water heater that goes really hot during the day and coasts through the night. Same idea for your freezer.

Heck I’d even blast my AC to ten degrees below where I want it during the day and then ride out the night.

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In certain parts of the US with retail choice this is already a reality, check out Griddy[0] in Texas. They'll give you wholesale electricity prices which is all sweet and dandy until there's a shortage of supply (generally on the hottest days of the summer) and the price shoots up to $9000 per MWh. Honestly it's a great deal if you're willing to accept the risk associated with it (or work from home and can quickly race to your circuit breaker and shut off the power when the price spikes).

[0] https://www.griddy.com

In the UK, Octopus Energy[0] have a tariff like this. They have a 35p / kWh price cap to limit that risk. With the average price of electricity around 15p / kWh here, it means the risk isn't too great as long as the shortages don't go on too long.

[0] https://octopus.energy/agile/

Sounds like something easily automated. If the electricity price goes above x, cut off power to a, b, c, leaving on d.

and switch d to battery

> I think if we had variable pricing that matched the availability of renewables, consumers would shift quickly.

If you dig around enough, you'll find plenty of stories of variable electricity costs. From what I understand, it's more common for business customers instead of residential. (Apparently chillers that freeze water overnight with cheap electricity to run daytime air conditioning is a thing.)

But anyway, I have a fancy powerwall and solar, but I only use it for backup. Why? There's no incentive to use the battery. It's 95% efficient, so if I use the battery at night, I get less net metering credits than if I just use it as backup.

A coworker recently showed me that they have a non commercial power plan/contract where they get hourly prices based on market rate. In South Australia where the sun is pretty intense, his power prices literally go negative for a few hours.

Now if you had variable loads or a battery you could schedule them to buy and sell power based on the market rate. Since very few people have the ability to do this, you can constantly beat the market on an almost daily basis. Tesla in fact already does this. Not only do they profit from this buying and selling, the grid becomes stabilized because the high and low demand periods become smoothed.

>Since very few people have the ability to do this, you can constantly beat the market on an almost daily basis.

That's incorrect usage of terminology because energy is not an investment. Nobody buys a kWh of energy expecting it to net a return year over year. It's used as a consumable like food or water. If you buy low and sell high you are engaging in trading, not investment.

Trading is about providing liquidity and the maximum liquidity a market needs depends on its size, not the number of traders. Those traders basically have to share a market and if there are too many traders then the profit per trader will go down. This is the biggest reason why trading (not investment) is zero sum. At some point enough is enough but this isn't necessarily as bad as many people portray.

A lot of industries are like this. Once everyone got a smartphone or PC the only way to grow faster is to displace a competitor. Trading in the stock market is usually a poor choice because there are plenty of professional businesses that are already providing enough liquidity.

Trading in the energy market can be a good choice precisely because the market isn't crowded as you said.

The scale of the required liquidity of the energy market is growing constantly. Every time a solar panel or wind turbine is installed, the need for variable power sources goes up. If we're going to go anywhere near the net zero target that many western nations have set, we're going to need _a lot_ of liquidity.

I believe that Tesla could hook my power wall into such a system if my local utilities offered it. Hopefully they do soon, because there's going to be major offshore windmills near my house soon.

It's going to be both. Tesla is working hard on mass-producing more affordable batteries. At the level of individuals it's already worthwhile. For 20K you can have enough Powerwall batteries to power your home when the sun isn't shining. 20K isn't that much on a 300-500K house. Competition will come and the price will come down more.

Couple that with automated buying/selling of renewable power at different times of the day, more efficient home insulation and... I'd say we're nearly there.

> For 20K you can have enough Powerwall batteries to power your home when the sun isn't shining

Huge amount of money to get off the grid - how many years of bills is that?

I have a 4kW system up here at 56 degrees north, and there's no way I could go off grid with it because the seasonality is huge; I can't store power all the way through the winter. I get it from the big offshore windfarms instead.

Renewable power and everyone being off-grid are not the same. I think we'd all like to be off-grid, but it won't be possible for everyone (eg: people living in apartments).

Curious to know, how much power do you get during the winter vs summer?

CATL, BYD, LG Chem , Panasonic and numerous new entrants stepping up their game due to Tesla competition. Hope there is cooperation too.

India without any Li ion manufacturer is trying very hard to get at least 1 or 2 off the ground with production linked incentives and a few business houses have entered.

I think the best thing we could do if we went to pricing like that is to have a meter next to your thermostat that tells you have much you're paying for electricity right now. That would make the mental equation much less abstract and immediate, further push people towards the behaviors you mention. But on those specifics:

1) Unfortunately most workplaces don't have a place to charge your car. That should change

2) Laundry is problematic for households with 2 adults & a few kids. Multiple loads can't be automated that way, so not running laundry after 5:00 pm isn't an option many days.

3) You can can have a high-efficiency on-demand hot water heater with an external tank to hold X amount of hot water for use throughout the day. Heating your home is more problematic: the hot water loses about 5-10 degrees per cycle through the house & back to the boiler, so you'd still need to run the unit on cold nights.

4) Fridge/Freezer: I like the idea, but it could be a food safety risk... I'd rather see units designed with that particular use case & required insulation in mind to ensure food was always kept at safe temperatures, even if it meant paying the .30 for short spurts over night.

5) AC: I wish everyone would do this sort of thing already with thermostat timers. If you have a small apartment with window units, timers at outlets should automatically shutoff living/dining units. Bedroom should have a high temp (though comfortable enough to sleep through) set for the cutoff since you're sleeping anyway. If your home needs more than 3 window units, it's generally more energy efficient to get central air (though upfront costs are high) and you can get multi-zones to only cool the areas needed, further improving efficiency.

Basically, I think a lot of the things we'd do to deal with variable pricing could already be done to reduce usage.

There are two big issues with just having residential consumers pay the spot market price.

1: not all if the costs are energy related. In fact, the cost to build and maintain the transmission and distribution systems is quite substantial. But that cost is for an average amount of energy over a number of years so it’s hard to turn that into a floating market value

2: There are socioeconomic factors that need to be resolved. Someone who works nights can’t avoid using power during high price times as it may be the only time to do chores. Or someone who works two jobs who can’t afford any fancy equipment to time shift use.

> 1) Unfortunately most workplaces don't have a place to charge your car. That should change

I think this correlates with EV sales. In the places that have lots of EVs you will find employers that have chargers.

Elon Musk said it in one of his presentations, something like "we sell cars whereever we put in superchargers".

The water heater thing has existed in the UK for years, it's called a storage heater.

The current market operate by people bidding to supply demand in the future. The market say "I want to buy power a certain amount between specific hours at a specific date" and the power operation can say "I will obligate to supply that energy at that time and date at this price". Batteries could at any time jump in and bid below that of any current bidders.

In that aspect we already have variable pricing. Individual customers usually don't see this, but I suspect the primary reason has more to do with averaging out the cost over time and not exposing individuals to the internal details of the energy market.

If you install your own panels, you can of course simply sell back to the electricity company.

In South Australia, a few roof panels, gets you enough credits to essentially run the AC without needing to consider the power cost.

That depends, full AC draws 5kw for me, so you'd need probably a 10kw system to get coverage for most of the day, and that's a big one, I think requiring a 3 phase connection. I dare say unless you have a fortunate roof shape (all flat or pointing all the right way) you wont be able to fit that on either..

Ah yes, I was being too loose in my language. I should have said: "gets my father enough credits, so HE does not worry about the costs of running the AC", which upon reflection might only be during and and the evenings"

> I hate the argument that we’re just waiting for batteries now.

Hopefully it’s not that simple. If the existing renewables output of an area is high, is it a good idea for me to build more capacity? I could just saturate the market and be stuck with low margins.

But if storage is coming, that could tilt the playing field a bit. I’d I do decide to gamble on it, now there’s even more reason to build storage, whether I build it or someone else does. In fact if I do both, I may be able to buy someone else’s surplus at a discount to resell and as a hedge against outages in my farm.

In theory that's nice, but in practice, you need power when you need it, and the energy companies / pricing will adapt. My parents had variable rates for a while, so electricity was cheaper at night, so they'd do things like the laundry at night. But in practice, the difference was negligible, especially as we started to add more and more daytime technology (like PC's) to the house.

There are a lot of creative implementations of demand response and time of use rates, but the price curve is crazy (see slide 7 [1]). To achieve a 10% reduction in electricity usage in the evening, you have to give people a 80-90% discount on their electricity at other times. BUT, "smart" water heaters, thermostats, etc. improve these numbers dramatically.

Designing these programs/prices/policies is a huge industry, and I happen to know a good bit about it because we work on helping utilities design these programs at Kevala (shameless plug: we are hiring [2])

[1] http://files.brattle.com/files/7390_price-enabled_demand_res... [2] https://kevalaanalytics.com/positions/

Octopus energy in the UK has something like this https://twitter.com/energystatsuk would be great if you could push energy back to the grid and get paid for it too

This already exist in some places (for example Amber and Powerclub in Australia).

The issue is it's more effort than most people are happy to exert. They are used to flicking a switch having the appliance on whenever they want it. To change that will either involve much higher prices, a substantial shift in the way we think about energy, or an improvement in technology to allow the load shifting to happen in the background without the user noticing.

We turn to batteries instead because it's easier to build something than it is to change behaviour.

For low level residential use batteries might be cheaper. For industrial and commercial use where the scales are higher, demand shifting is probably cheaper.

If spot pricing for residential consumers was universal instead of niche, I suspect the technology would rapidly develop to meet this requirement.

That water heater idea is interesting. You could put a thermostatic valve on the output that mixes in cold water so the output was always the same temp no matter what the inside is. Usually people turn the temp down to save money, but if you can heat it way up when energy is cheap, that might change completely.

At least in Germany that's already the standard plumbing practice: a mixing valve on the tank outlet ensures the tap temperatures are safe. This is important because the tank is required to periodically heat to 65C to kill legionella bacteria, and with solar input can heat to as much as 85C, so without such a valve the tap temperature would be unpredictable and sometimes dangerous.

What may be easier is to move the heating element to the top, and add a pump to move water to the top when heating.

Hot water will stay at the top of the tank, so that means you can use most of the hot water without a significant drop in temperature.

There's a company making tanks like this: https://www.youtube.com/watch?v=z1Z4JCoPAGc

We don't need batteries we just need a massive change in lifestyle including self-managed power cuts and making our houses freezing cold so they're tolerable at night when we can't run the AC. Sounds... not ideal

We used to have things called storage heaters in the UK which were electrical heaters (and so were expensive) designed to use the slightly less expensive night-time electricity to heat up big bits of concrete contained within them, which then leaked (not enough) heat during the day. They were not good at all

Some states have this. I remember a friend in new york had a timer on his electric water heater to heat it at night when power was cheap.

But you are right - market forces are extremely powerful in their ability to optimize things.

I think it's pretty common to have time-of-use pricing (that's what my provider calls it, and I am on the plan), but it's relatively fixed. Ours switches schedule twice a year. So you can get used to it, I only charge our EVs after 10pm for example. But if it changed dynamically, I'd need to have a lot of automation in place to react, because it would get tiring to personally pay attention to price all the time.

>Some states have this. I remember a friend in new york had a timer on his electric water heater to heat it at night when power was cheap.

This has been a thing in Australia too, under the decades-old assumption that midnight coal is the cheapest period of power. There have been projects to change the boiler systems to 1) heat at midday instead of midnight, to reflect the changed cost-curve caused by solar, and 2) randomise the exact period of heating, to spread the demand over a range rather than causing a huge spike at 12:00 exactly.

As an upper midwesterner, that would be an incredibly hard sell. You could whip up support for coal again in heartbeat.

Renewables are a great idea in theory, but in reality don't jive well with people in the non-windy, non-sunny areas that also get really damn cold. It's sad to say it but nothing can beat what natural gas and coal can do already. They're cheap and can be used to generate electricity at an extraordinarily affordable rate. At the end of the day, that's the #1 thing most people are going to care about. If you told people here their electricity bills would double, they'd actively go out and demand the current politician step down.

If I understand what you're saying, it is that there's little wind, not much sun and it's extremely cold in say, North Dakota, so fossil fuels are cheaper there? Seems to be about a 10 mph avg wind speed [1] and sunny about half the time in daylight hours in winter [2]

[1] https://www.ndsu.edu/climate/North%20Dakota%20Data/Yearly%20...

[2] http://www.bismarck.climatemps.com/sunlight.php

So how do you handle peak periods but it happens to only be a low wind generation day? Just tell everybody brownouts are in effect? The only reason that happens in enormous cities like LA, SF, and Austin TX is because they have way too many people drawing power. The grid can't be built faster than people can move in.

In terms of electricity generation, this is why batteries are a monumental step towards making green energy feasible. It accounts for these peak periods, capitalizes off of them, then reuses the stored energy when energy generation is low.

I'd burn fossil fuels too huddled around the furnace in the upper midwest in the winter. To hell with the greens.

I'm not saying we shouldn't have green energy. I'm saying it's not feasible yet. You're damn well sure it's not feasible for {insert major metropolitan area here}.

You'd have thought that high demand would increase fossil prices? No, they're cheap in North Dakota because of all the fracking there.

I grew up on the beach in California. North Dakota in the winter sounds like a frigid, dark, petroleum smelling hell hole to me.

The upper midwest has comparable climate to Russia. You know, the Russia both Napolean and Hitler invaded. It's not bad right now, but on occasion we get -10F weather. I know southerners think it's the worst but it's really not. Snow and ice is a bigger bitch to deal with than the temp.

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