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Who's afraid of Solar PV?

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Re: Who's afraid of Solar PV?

#21

Post by jorgem »

maxerickson wrote: post #13
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…

I doubt it gets that ugly. The per gallon charge for municipal water in the East Bay is ~$0.005. People like flushing their toilets and taking showers, so conservation only eliminates so much.

I dunno. My water bills average $200/mo, for a single home (no pool, mostly drought resistent yard, etc). We're in an area with low density (out in the country).

I pay about $120 in fees. Then the water is the rest of it.

In winter, when we use less water, my bill goes down to about $130. $10 worth of water per month.

Re: Who's afraid of Solar PV?

#22

Post by Andys »

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…

I propose a new type of grid with electronic signaling of spot prices.

For heavy duty appliances (eg. air conditioning, water heating) the consumer pre-programs it with a desired average cost and a maximum price per kWh.

Then as demand and supply rises and falls on the grid, the spot price changes, and the devices receive signals and turn themselves on and off as needed. (There would be a certain minimum of fixed-price energy per month to make sure financially strained families never have to go without any)

Re: Who's afraid of Solar PV?

#23

Post by brc »

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…

>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 compensated for pushing energy back into the grid.

You're asking people who cannot afford the expensive technology to subsidise those who can. This is the exact reverse logic of most progressive taxation regimes.

>The question is; would 5% of the driving population buy a $50k car if they no longer had to pay for fuel or battery packs? Financially that would probably put it closer to a BMW.

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.

And for what end? Just so you can have some type of boutique distributed power generation system?

>What's needed is the will to make it happen.

No, what's needed it pots of other peoples money.

I've spent the best part of 5 years trying to hose down the jetsons fantasies of people pushing ridiculous schemes like this as not only unworkable, but inequitable for forcing up a basic cost input of life - energy - for effectively vanity purposes of a small subset of the population. I usually cop a pile of flamebait and downvotes each time, but I do so because there seems to be a mass delusion going on, and this has become one of those things you can't say.

Re: Who's afraid of Solar PV?

#24

Post by nl »

(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 at least it gets really, really hot. For example in February 2009 we had 6 Consecutive days over 40 °C (104 °F) and a maximum of 45.7 °C (114.3 °F)[2], and then in November 2009 we had 6 Consecutive days over 38 °C (~100 °F)[3]

These peak temperatures occur earlier in the day than the typical power spike (12pm-4pm instead of 5pm-7pm), and caused huge power spikes (from air conditioner usage), and this often causes power companies to have to shut off power (they have a policy of doing rolling blackouts when they don't have enough capacity).

This peak demand is much, much higher than the average peak demand shown on the linked article, and these are the peaks the power companies invest to meet. If these peaks are reduced by solar panel usage (which they should be, since the come during the best time for solar production) then it should reduce the requirements for larger power stations.

[1] http://www.heraldsun.com.au/opinion/power-play-between-feder...

[2] http://en.wikipedia.org/wiki/Early_2009_southeastern_Austral...

[3] http://en.wikipedia.org/wiki/Late_2009_southeastern_Australi...

Re: Who's afraid of Solar PV?

#25

Post by brc »

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…

You still need the conventional energy base. You cannot have a grid reliant on solar, because sometimes the sun doesn't shine for days on end.

Solar can top up the grid, and correlates well with air-conditioning driven demand on hot days. But it doesn't coincide with peak load - especially in winter - and will always be a diffuse power source.

You would not only need a cost effective storage solution (and none is in the foreseeable solution) you also need a lot of available space. Even if the panels were virtually free - there still remains large problems with solar power as a baseload energy source. If you solved the storage problem - cheaply - you'd still need 4 - 5 times the collecting capacity to get close to being able to reliably produce power over even a 48 hour period.

It's a great boutique energy solution, particularly for remote usage. But large scale electricity generation will remain the dominant energy source well into the foreseeable future.

Re: Who's afraid of Solar PV?

#26

Post by nl »

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…

Advice to entrepreneurs: finding a cost-effective way to store solar energy for 4 hours will be worth more than another 2% increase in efficiency. And inventing instant-on conventional-fuel plants will also make a huge difference in GHG emissions.

This is a solved problem. It's called pump storage[1], and is in use world wide. The US has some existing pump storage power plants (eg [2]), but typically they are used to smooth out demand on non-renewable generators (Coal, Nuclear etc).

[1] http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity

[2] http://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Stat...

Re: Who's afraid of Solar PV?

#27

Post by nl »

politician wrote: post #17
danmaz74 wrote: post #8

Earlier quoted context omitted.

"We get new sunlight every day, but the fresh water that we have is all we have." Actually, we get new fresh water every other day - it's called rain.

If we actually got new water every day it'd be arriving on meteorites. Of the water present on the planet, 97% is salt water which is unusable for drinking or agriculture. Of the 3% freshwater, 68.7% is locked in glaciers. So, 1% of the water on the planet is liquid and most of that is underground. We don't really have a lot and things like fertilizers damage what we have. It turns out that the amount of fresh water…

In South Australia we are building a wind and solar powered desalination plant too: http://en.wikipedia.org/wiki/Port_Stanvac_Desalination_Plant

Re: Who's afraid of Solar PV?

#28

Post by maxerickson »

jorgem wrote: post #21
maxerickson wrote: post #13

Earlier quoted context omitted.

I doubt it gets that ugly. The per gallon charge for municipal water in the East Bay is ~$0.005. People like flushing their toilets and taking showers, so conservation only eliminates so much.

I dunno. My water bills average $200/mo, for a single home (no pool, mostly drought resistent yard, etc). We're in an area with low density (out in the country). I pay about $120 in fees. Then the water is the rest of it. In winter, when we use less water, my bill goes down to about $130. $10 worth of water per month.

I guess the $200 is ugly enough as it is.

Re: Who's afraid of Solar PV?

#29

Post by greendestiny »

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 worrying about power prices increasing in South Australia again.

Re: Who's afraid of Solar PV?

#30

Post by caf »

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…

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 money.

I'm not sure I agree that the economics work out exactly as described, though - if it would be worth paying for everyone's lithium car battery packs to do this, then it would be even more profitable to build a giant lithium storage battery in a central location.

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