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Who's afraid of Solar PV?

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Re: Who's afraid of Solar PV?

#31

Post by MikeCapone »

slapshot wrote: post #4

An interesting problem is highlighted on that graph: solar seems to be peaking around mid-day, but energy demand peaks at 5 - 7 pm when solar is pretty weak. The curves showing pre- and post-solar have almost identical peaks; solar hasn't yet successfully reduced peak load. (The California energy system posts a similar graph, with a similar shape: http://www.caiso.com/Pages/TodaysOutlook.aspx , made worse by the fact…

One potential solution is grid-scale liquid metal batteries:

http://lmbcorporation.com/

http://www.ted.com/talks/donald_sadoway_the_missing_link_to_...

Re: Who's afraid of Solar PV?

#32

Post by caf »

jorgem wrote: post #9

>> The unspoken fear of all utility managers is the “Death Spiral Scenario”. >> In this nightmare, a utility commits to build new equipment. >> However, when electric rates are raised to pay for the new plant, the rate shock moves customers to cut their kWh use. We have a "death spiral" in water prices in my local (southern California) water district. There was a drought. People were asked to conserve. People conserv…

If the water utilities are smart they'll increase the fixed "connection charge" component of their bills to cover more of the fixed infrastructure costs.

Re: Who's afraid of Solar PV?

#33

Post by MikeCapone »

brc wrote: post #23
reitzensteinm wrote: post #12

Earlier quoted context omitted.

We don't need any breakthroughs. Electric cars could handle the entire peak load with today's technology, the right incentives, and capital flowing in the right place. The peak load for South Australia was 1.8 gigawatts. There are 1,275,041 motor vehicles registered in SA. If you could get all of them turned into electric cars plugged into the grid, it would be a 1.4 kW power drain per vehicle, which is less than the…

>So if everyone had the cheapest Model S, kept it plugged in with the ability to send power back into the grid, and didn't mind that their car was sometimes down to 20% charge, you could power the entire grid on solar alone. The OP said cost effective, not pie-in-the-sky. Even if you took out the battery packs and sold them separately, the cost would exceed 10 years worth of electricity supply. >Owners can be heavily…

Power plants aren't free, people pay for the service they provide. If you can replace them with less expensive batteries (especially since people will be ready to buy electric cars for their main benefit, which is transportation -- getting paid to lease you battery is a side benefit) to store cheap solar power, that's a good deal, not a subsidy.

Re: Who's afraid of Solar PV?

#34

Post by reitzensteinm »

SoftwareMaven wrote: post #20
reitzensteinm wrote: post #12

Earlier quoted context omitted.

We don't need any breakthroughs. Electric cars could handle the entire peak load with today's technology, the right incentives, and capital flowing in the right place. The peak load for South Australia was 1.8 gigawatts. There are 1,275,041 motor vehicles registered in SA. If you could get all of them turned into electric cars plugged into the grid, it would be a 1.4 kW power drain per vehicle, which is less than the…

Until fast-charge batteries are a reality (such as the carbon-laced Li-ion discussed previously here), people very much will mind their car being at 20% charge. That means they don't get to drive until the next day, except 5-7pm is key commuting time, when they need to drive now .

My proposal was not that people would sacrifice 80% of their battery. The first half was exploring the limits of the idea. I was suggesting 20-40%.

Re: Who's afraid of Solar PV?

#35

Post by brc »

MikeCapone wrote: post #33
brc wrote: post #23

Earlier quoted context omitted.

>So if everyone had the cheapest Model S, kept it plugged in with the ability to send power back into the grid, and didn't mind that their car was sometimes down to 20% charge, you could power the entire grid on solar alone. The OP said cost effective, not pie-in-the-sky. Even if you took out the battery packs and sold them separately, the cost would exceed 10 years worth of electricity supply. >Owners can be heavily…

Power plants aren't free, people pay for the service they provide. If you can replace them with less expensive batteries (especially since people will be ready to buy electric cars for their main benefit, which is transportation -- getting paid to lease you battery is a side benefit) to store cheap solar power, that's a good deal, not a subsidy.

>If you can replace them with less expensive batteries

Agreed. And when that is the case, then this behaviour will appear at large and be taken up enthusiastically.

At the moment this manifestly isn't the case (stored solar by batter cheaper than large-scale power), so any calls for it to happen is usually a disguised call to force it to happen by producing regulatory benefits to a small subset by driving up the cost for others.

I have zero problem with people electing to spend their own money on solar + battery storage. I find the tech interesting. I am simply determined to point out whenever I see this type of call that usually this means taxing poorer people to pay for richer peoples desires.

Re: Who's afraid of Solar PV?

#36

Post by rdl »

reitzensteinm wrote: post #12
slapshot wrote: post #4

An interesting problem is highlighted on that graph: solar seems to be peaking around mid-day, but energy demand peaks at 5 - 7 pm when solar is pretty weak. The curves showing pre- and post-solar have almost identical peaks; solar hasn't yet successfully reduced peak load. (The California energy system posts a similar graph, with a similar shape: http://www.caiso.com/Pages/TodaysOutlook.aspx , made worse by the fact…

We don't need any breakthroughs. Electric cars could handle the entire peak load with today's technology, the right incentives, and capital flowing in the right place. The peak load for South Australia was 1.8 gigawatts. There are 1,275,041 motor vehicles registered in SA. If you could get all of them turned into electric cars plugged into the grid, it would be a 1.4 kW power drain per vehicle, which is less than the…

I think cycle counts for expensive low mass batteries are going to be a lot more of an issue than you think; it would be cheaper to put thermal, flywheel, or gravitational batteries as retrofits into substations and transformers instead, I think, or at least to put them at fixed locations like businesses which draw a lot of power. Even better, it's a free backup power supply for when the grid is down, too.

We agree on some form of distributed storage and maybe generation, though, combined with a smarter grid. It's all current or 5 years out technology.

Re: Who's afraid of Solar PV?

#37

Post by reitzensteinm »

brc wrote: post #23
reitzensteinm wrote: post #12

Earlier quoted context omitted.

We don't need any breakthroughs. Electric cars could handle the entire peak load with today's technology, the right incentives, and capital flowing in the right place. The peak load for South Australia was 1.8 gigawatts. There are 1,275,041 motor vehicles registered in SA. If you could get all of them turned into electric cars plugged into the grid, it would be a 1.4 kW power drain per vehicle, which is less than the…

>So if everyone had the cheapest Model S, kept it plugged in with the ability to send power back into the grid, and didn't mind that their car was sometimes down to 20% charge, you could power the entire grid on solar alone. The OP said cost effective, not pie-in-the-sky. Even if you took out the battery packs and sold them separately, the cost would exceed 10 years worth of electricity supply. >Owners can be heavily…

First off, I specifically said that the first lot of calculations was based on unreasonable assumptions, to gauge the size of the problem.

Attacking them because they're "pie in the sky" frankly sounds like you're deliberately misinterpreting me, or at least you didn't bother reading the post.

Secondly, the scheme I'm proposing does not require any government subsidies. The money comes from selling the power back to the grid.

With my proposed figures - 5% EV ownership (63,752 cars), 40% battery usage sold back to the grid, you could reduce peak power usage by 15%. South Australia spent ~$990 million on electric power last year (not exact figures; based on 619k households from the census with an average spend of $1600).

Assuming 15% reduction in peak power is a 10% reduction in cost (which is reasonable, because capital costs and fixed running costs dominate electric spending expenses), that yields $99 million a year in savings.

The cost of 63,752 Model S cars is $3.1 billion. However, you have to look at the marginal cost of purchasing a Model S, vs whatever car the high end of the market is buying anyway, AND subtract the spending on fuel.

We're saving $1571 per car per year. Tesla's prepaid replacement program is $12,000 (over ten years), which eats a big chunk of it, however we're also charging with cheap peak solar (the abundance of which is causing this issue to begin with), plus maintenance is cheaper.

BMW 5 series MSRPs are from $38k-68k. Taking the lower end of that, we're paying a $12k premium for a car with significantly lower maintenance costs and little to no fuel costs.

Could you get 5% of cars on the road taking that deal? I don't know. Today? Maybe, maybe not. But I do know that as the price of peak solar and battery technology falls, it will go from being a 'maybe' to a 'no brainer' over the next ten or fifteen years.

In any case, I may be wrong in my analysis. I'm merely presenting an argument for the way I see it. If you disagree on a specific point, I'd be happy to talk more about it, but nothing I wrote deserved your response.

Re: Who's afraid of Solar PV?

#38

Post by shirro »

greendestiny wrote: post #29
nl wrote: post #24

(I live in South Australia, and I've previously worked on electricity energy trading systems here) This is a pretty good article, but misses a little context that maybe helpful to non-Australian readers. 1) Power bills in Australia have been rising rapidly over the last couple of years. The reactionary response has been to blame the new Carbon Tax, but the real causes are much more complex[1]. 2) In South Australia a…

As another South Australian I have to say this article makes me a little concerned about further price rises of mains power to make up for the shortfall. Although the long term benefits of Solar are amazing the short term situation for power infrastructure here could be a problem. *Edit: I can see a flatter usage profile should probably mean cheaper power, but still I think there is some justifiable paranoia in worry…

Another South Australian. Power is just the next thing to be disrupted by technology changes.

I think we need smart meters and a more market driven approach to retail pricing. Peak electricity costs can go through the roof and people will respond by shifting their usage to alternatives or different times when there is less demand and prices are lower. Unfortunately there is no market transparency and we are paying for retail electricity without any real understanding of the underlying costs. We are paying ridiculously increasing amounts for electricity so we can build infrastructure to handle peaks that many would avoid if there were market pressures on consumers. Changes like rooftop PV and wind farms are only a part of the picture.

Re: Who's afraid of Solar PV?

#39

Post by reitzensteinm »

caf wrote: post #30
brc wrote: post #23

Earlier quoted context omitted.

>So if everyone had the cheapest Model S, kept it plugged in with the ability to send power back into the grid, and didn't mind that their car was sometimes down to 20% charge, you could power the entire grid on solar alone. The OP said cost effective, not pie-in-the-sky. Even if you took out the battery packs and sold them separately, the cost would exceed 10 years worth of electricity supply. >Owners can be heavily…

So you want to subsidise the purchase of expensive cars to the point where it is financially a good deal. This magic money no doubt comes from other taxpayers. The proposal isn't a subsidy. It's a straight market payment for an economic benefit - the difference in cost between off-peak and peak electricity is real, and this means that storing off-peak electricity and releasing it at peak is an activity that's worth m…

Well, the benefit is that it combines the capital costs of owning a vehicle and storing energy. Many people will be purchasing a 160+ mile range car, but day to day use only 20-30 miles of that - an unused capacity large enough to power an average house for over 24 hours.

This is in contrast to dedicated lithium ion batteries, which just don't work out economically. Otherwise you're right - the utilities would do it themselves at scale.

Re: Who's afraid of Solar PV?

#40

Post by reitzensteinm »

rdl wrote: post #36
reitzensteinm wrote: post #12

Earlier quoted context omitted.

We don't need any breakthroughs. Electric cars could handle the entire peak load with today's technology, the right incentives, and capital flowing in the right place. The peak load for South Australia was 1.8 gigawatts. There are 1,275,041 motor vehicles registered in SA. If you could get all of them turned into electric cars plugged into the grid, it would be a 1.4 kW power drain per vehicle, which is less than the…

I think cycle counts for expensive low mass batteries are going to be a lot more of an issue than you think; it would be cheaper to put thermal, flywheel, or gravitational batteries as retrofits into substations and transformers instead, I think, or at least to put them at fixed locations like businesses which draw a lot of power. Even better, it's a free backup power supply for when the grid is down, too. We agree o…

To clarify, I am very much not in favor of standalone lithium ion battery packs; I'm just talking about harnessing the inevitable unused capacity of electric car batteries to smooth out the grid. The revenue from which could incentivize faster adoption of EVs, since the marginal cost of getting an EV is falling. If you had to pay for them as dedicated energy storage, it would be horrifically expensive.

As you say, many other technologies are far more suited to this kind of use.

You may be right about the cycle count; EVs are designed to be daily drivers, but charging and discharging 40-50% of a battery daily is likely more punishing than 10-20%. Though even if that is the case, it would just push my analysis 10 years into the future, when cheaper batteries and PV will make up the difference.

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