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Rate-design wars are the sound of utilities taking residential PV seriously

blogs.berkeley.edu

21–27 of 27 posts

Re: Rate-design wars are the sound of utilities taking residential PV seriously

#21
I can understand why people are hostile towards utilities for trying to change their pricing. However, keep in mind that utilities are some of the most regulated private companies in our economy. Their rates have to be approved by the government. They are allowed to make a profit, but not a big one. If they start making losses, then the lights are going to go out ...

For those who have suggested going off the grid, keep in mind that even in sunny California, we do have a rainy season. I've reviewed my friends' electric bills with them, and even those with quite large PV installations are still net consumers through most of the winter. To make it through, you'd likely need a generator (dirty, loud, expensive).

I think the bigger issue here is that people have made long-term commitments (20 year lease agreements) to finance solar installations, counting on net metering and a continual increase in power rates. If the utilities change the game, you're going to screw over a lot of fairly well-off consumers (vs. the mean), which doesn't usually go over well.

Re: Rate-design wars are the sound of utilities taking residential PV seriously

#22

Dig a 15 meter pit 5 meters across and suspend a 5 meter cube of ferro-concrete on a cable feeding onto a drum above it connected to a gearbox and motor/generator. Attach this to your PV and then relax.

I don't have time to look for the cite now, but I've read a proposal to build electric traction railways up some steep slopes in SoCal, then load up cars of rocks, mine tailings, slag, etc. The trains would head up the mountain at night when electricity is in surplus, then back down in the daytime when demand is near peak.

Seems outlandish, but the calculations predicted very high efficiency and comparatively low cost per MWh of storage.

Re: Rate-design wars are the sound of utilities taking residential PV seriously

#23
post #13

The IBP (tiered rating) isn't a birthright of utilities, geez. It's a conservation measure! Whether I shave off my higher-tiered consumption by changing my thermostat, changing my lighting or by putting in solar, that lost high-profit consumption isn't the company's property, it's mine to do something else with.

I don't think most utilities have a beef with shaving off high-tier consumption (well, I'm sure they miss the revenue, but they are not stupid enough to go back on years of telling their customers to conserve).

Their bigger concern is net metering, by which I can sell them solar power during peak hours at their retail rate of, say, $0.45/kWh and then buy it back from them at, say, $0.06/kWh at night, or maybe even 6 months later in the dead of winter.

Not paying for power you didn't use is one thing, but using the power company's own transmission network to arbitrage its rates with no fee does seem long-term unsustainable. If the current rates reached their ultimate conclusion, the power companies would have to make massive, massive investments in storage systems capable of buffering months worth of demand, as their net revenues trend towards $0.

Re: Rate-design wars are the sound of utilities taking residential PV seriously

#24
post #18

Earlier quoted context omitted.

You could, but you would need to purchase and setup batteries.

The other option is to grid-tie, but agree not to sell any power back to them (which can be configured in the inverter). You would then use utility power when you don't have enough solar output to meet your needs. Disclaimer: I have read WAY too much Home Power magazine over the last decade. I could design said system in about 20 minutes, part numbers and all. [ http://www.homepower.com/ ]

For most home solar installations, this would dramatically skew the financial break-even for solar installation.

Re: Rate-design wars are the sound of utilities taking residential PV seriously

#25

Earlier quoted context omitted.

I'm uninformed, "grid saturation" meaning what?

I'm not positive, but I might imagine that it's that the solar power generated by that particular grid either equals or exceeds the amount used by it. If there's multiple grids it could be that the residential area is nearly self sustaining during the day, and they don't have the capability to move that generation successfully to the other places that need it because the grid interchanges weren't built with that in m…

That's exactly what it is. See presentation here: http://www.heco.com/vcmcontent/StaticFiles/pdf/LVM/LVMMECOPu...

It appears that there are neighborhoods in Hawaii where the PV generation capacity is approaching the max load of the circuit.

Re: Rate-design wars are the sound of utilities taking residential PV seriously

#26
post #11
post #8

Hilarious. "they want to further reduce the incremental energy price by implementing a fixed monthly charge on each customer, aimed at covering some of the costs of retail distribution, metering and billing." That's straight out of the 1975 hippie classic "Ecotopia: The Notebooks and Reports of William Weston" - and is one of the Casus belli California cited when seceding from the union in that book.

I keep getting notes from SoCal Edison with each bill wanting to tack on fees for every little thing. New distribution lines, cleaning up their nuclear mess at San Onofre. In other businesses those are costs of doing business and are factored into their balance sheet rather than getting directly passed on to the customer.

Just so long as you don't start setting up artillery on the sierra nevadas.

Re: Rate-design wars are the sound of utilities taking residential PV seriously

#27
post #17

Dig a 15 meter pit 5 meters across and suspend a 5 meter cube of ferro-concrete on a cable feeding onto a drum above it connected to a gearbox and motor/generator. Attach this to your PV and then relax.

Google says density of concrete is 2400 kg / m^3. Multiply that by 5x5x5 m^3 and you have 300,000 kg of concrete (300 metric tons). m = 300000 kg g = 9.8 m/s^2 h = 10 m The total amount of potential energy you can store is: m * g * h = 29400000 J = 29.4 MJ The more customary unit of energy in electric circles is the kW hr. Converting a kW hr to joules gives: 1 kW hr = 1 kJ hr / s = 1000 J hr / s * (60 s / min) * (60…

Thanks for that, I thought it would give around a couple of days of backup, however I had completely fudged the numbers somewhere along the line.
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