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Project Sunroof

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Re: Project Sunroof

#81

Post by bostonpete »

thrownaway2424 wrote: post #73
jvm wrote: post #63

Forgive my ignorance, what does one do during non-insolated hours? Do solar cells typically come with battery packs or does one just pull from the grid? If the latter then the cost savings are a bit less impressive than stated. Also can you put power back into the grid in San Francisco? Is that benefit included in the cost savings estimate?

Solar power systems don't necessarily come with batteries but a decent installation company should be able to propose and implement an integrated system. The Tesla battery pack is an example of some recent innovation in that area. You can sell power into the grid but PG&E only has to pay you wholesale rates, 3-4 cents per kwh, not what they are charging you to take the same amount of energy out, which is 34 cents per…

> It's basically a scam.

Why is it a scam that PG&E won't pay you more for power than they can buy it wholesale?

Re: Project Sunroof

#82

Post by dicroce »

swalsh wrote: post #18

Weird, it says it covers Boston but when I put my Boston address (single family in the city of Boston itself) it says they haven't reached the address yet.

I put in an address and it couldn't find it... Then I cleared it out and put in the address more slowly... When I did that I noticed that it found it in the drop down... so I selected it and THEN it worked... It seems like unless you put in EXACTLY what they have in the DB, it won't work... (in my case, I left off the "avenue" in my address).

Re: Project Sunroof

#83

Post by thrownaway2424 »

bostonpete wrote: post #81
thrownaway2424 wrote: post #73

Earlier quoted context omitted.

Solar power systems don't necessarily come with batteries but a decent installation company should be able to propose and implement an integrated system. The Tesla battery pack is an example of some recent innovation in that area. You can sell power into the grid but PG&E only has to pay you wholesale rates, 3-4 cents per kwh, not what they are charging you to take the same amount of energy out, which is 34 cents per…

> It's basically a scam. Why is it a scam that PG&E won't pay you more for power than they can buy it wholesale?

The 3-4c wholesale rate is for base power (giant infrastructure generators, hydroelectric dams and such things), but solar knocks the top off the mid-day demand curve, at which time PG&E is paying much more for "peaker" power generation. But they don't have to pay you the peaker rate, they pay you the baseline rate.

Anyway, to my mind, any system in which current comes out of your PV installation at 3 cents and flows directly into your neighbor's air conditioner at 34 cents is a prima facie scam.

Re: Project Sunroof

#84

Post by TTPrograms »

birken wrote: post #60

I live in San Francisco and just had a solar system installed last week, so I have a few comments about this. 1) It vastly overestimated how big a solar system that could fit on my roof (by about 5x). It didn't care about chimneys or skylights (which are easily visible through Google maps), nor SF fire code which states that you need a 3-foot empty pathway on both sides of the crest of your roof [1]. So for almost ev…

Is the cost primarily proportional to the size, or do inverters present a major fixed cost?

For the former it doesn't really matter how much you can cover, as it's simply an investment with a certain rate of return that has the amount you can invest limited by roof area.

Re: Project Sunroof

#85

Post by thrownaway2424 »

jsprogrammer wrote: post #78
thrownaway2424 wrote: post #73

Earlier quoted context omitted.

Solar power systems don't necessarily come with batteries but a decent installation company should be able to propose and implement an integrated system. The Tesla battery pack is an example of some recent innovation in that area. You can sell power into the grid but PG&E only has to pay you wholesale rates, 3-4 cents per kwh, not what they are charging you to take the same amount of energy out, which is 34 cents per…

Is there no real solar power market then? If your local utility is a monopoly then you basically have to accept whatever the utility wants to pay you (even far below 'market' rate). You have no power to negotiate, only capitulate or try to get the local regulator to enforce fair trade.

Local conditions may vary, of course, but if just go with the completely unimaginative system, and you live in California in PG&E territory, there is no effective market.

Re: Project Sunroof

#86

Post by VLM »

uptown wrote: post #65

Are firefighters any less likely to enter a house fire where the roof is covered in heavy solar panels? I've heard stories, but never dug into whether it was anti-solar FUD.

It smells of the anti-hybrid astroturfing from a decade or so ago where numerous Ford and GM employees would be glad to tell you on social media that if you get into a car accident in a hybrid, emergency services will leave you to bleed out and die because its a hybrid so you should have bought a SUV or truck like a RealAmerican(tm).

My father in law did the volunteer fire dept thing in his rural area and its very depressing how quickly a typical house becomes unsaveable in a fire. So it is true that most houses with solar panels, in a fire, will end up a total loss, but that's true of most houses ... period, nothing to do with solar panels.

My advice from the frozen north is solar panels are extremely light weight compared to slush/snow covered shingle roofs, which don't seem to slow down firemen very much. The total mass of a couple inches of rain soaked slush snow is unbelievable, many thousands of distributed pounds on a typical roof.

Re: Project Sunroof

#87

Post by TeMPOraL »

andyl wrote: post #21

Fusion of maps, 3d modeling, electricity & lease rates, solar intensity, installers. Easy to use. This feels like something new and powerful. For society: I wonder if it is safe for so much power to be concentrated in one organization. As a technical accomplishment: I'm impressed.

> For society: I wonder if it is safe for so much power to be concentrated in one organization.

In general, it's probably not. But in this particular case it's been working very well for us so far.

Re: Project Sunroof

#88

Post by _delirium »

thrownaway2424 wrote: post #83
bostonpete wrote: post #81

Earlier quoted context omitted.

> It's basically a scam. Why is it a scam that PG&E won't pay you more for power than they can buy it wholesale?

The 3-4c wholesale rate is for base power (giant infrastructure generators, hydroelectric dams and such things), but solar knocks the top off the mid-day demand curve, at which time PG&E is paying much more for "peaker" power generation. But they don't have to pay you the peaker rate, they pay you the baseline rate. Anyway, to my mind, any system in which current comes out of your PV installation at 3 cents and flows…

Even peaker plants run ~15 cents these days, since the price of gas has fallen so low.

edit: I'm more familiar with the Texas grid, but beyond the cheapish price of modern peaker plants, in that case the most expensive input sources (small peaker plants, and esp. spot-market purchases) are rarely used at all. Demand prediction and management is good enough to avoid the more expensive inputs, through a mixture of local generation management and advance wholesale purchases on the DC interconnects. On the handful of days when some issue causes a shortfall, it would be valuable to buy residential solar inputs, but this happens about 5-6 days a year. To handle those days, most utilities have a savings-rebate program, where if you agree to reduce your usage between 2-5pm on these handful of days, you get a $0.60/kwh credit. So they solve their occasional peak problem by just turning your thermostat up 2º and "buying" the unused energy at a premium price.

Re: Project Sunroof

#89

Post by uptown »

VLM wrote: post #86
uptown wrote: post #65

Are firefighters any less likely to enter a house fire where the roof is covered in heavy solar panels? I've heard stories, but never dug into whether it was anti-solar FUD.

It smells of the anti-hybrid astroturfing from a decade or so ago where numerous Ford and GM employees would be glad to tell you on social media that if you get into a car accident in a hybrid, emergency services will leave you to bleed out and die because its a hybrid so you should have bought a SUV or truck like a RealAmerican(tm). My father in law did the volunteer fire dept thing in his rural area and its very de…

Seems like it's likely mostly anti-solar propaganda, but I guess there is some concern regarding the electrified nature of solar panels rather than their weight.

http://solarenergy.net/News/tackling-risks-solar-panels-pose...

I care little about the house in a fire. I do care about its occupants, and also the safety of the firefighters attempting to extract anyone still inside.

Re: Project Sunroof

#90

Post by drelihan »

Entered my info. Got a call within five minutes and was then asked the exact same info. Company said I don't use enough electricity to make it worth it. Wonder how much they had to pay Google for that lead
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