Tell me why PV systems are not a scam

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ggunn said:
...But believe it or not, some customers do not care about that; they just want as many modules up there as will fit in any way possible. We try hard to dissuade them when we encounter this; my company's work is on display with every system we install.
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Yes, this. I try to strike a balance with aesthetics of array design when it runs up against production goals. Many more customers are disappointed if I can't fit all the modules on the roof than if the layout ends up funky.

jumper said:
Don’t tell anyone here, but most normal people think most electrical is ugly, that is if they even notice it.
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In the electrical equipment beauty pageant, black-on-black solar modules definitely win first place. :D;)
 
gar said:
180117-1356 EST
In my area my cost of electrical energy is about $0.16 per kWH. My natural gas cost is about 1/5 of that for the same energy.

If I ran an engine generator from natural gas what overall efficiency could I get? If 80% and I could make effective use of the waste thermal (exhaust gas) energy could I overall beat 0.16 per kWH?

If I had a thermal solar array could I save any money?
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Gas turbines have just cracked 60%.... I believe the Wartsilla heavy diesel ship engines approach 50% thermal efficiency... a small natural gas engine maybe 30-35%. No way you'd ever see 80% even if you could recycle all the waste heat thru things like low pressure turbines, liquid-to-liquid heat exchanger to heat water for hot water/climate control, etc.

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As to the topic question, PV systems only make financial sense to me if you are living way off of where power is and have to pay for the POCO to bring power to you, POCO power is extremely expensive or unreliable, or possibly RVs or prepper-type situations. I've a friend in NV who lives on solar, not for any environmental reasons or tax breaks, but because it would have cost him somewhere north of $200k to get POCO power there.

I do find a lot of PV systems, especially small, turn-key ones, large on possibility and short on reality. I saw an ad not too long ago for a 'solar generator', and it showed the unit running a TV, lights, even a dishwasher and washing machine. What was in the fine print was that to run that washer, it would require several additional panels (not included in the base cost) as well as extra batteries.

That said, in my lifetime I believe that battery and panel technology will improve to the point where solar will be on par with, and possibly be cheaper than energy from coal and nuke plants.

Solar installs are practically non-existent here, for now.
 
Coppersmith said:
The roofs still seem to be pointing the wrong way.
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Tesla makes matching tiles without solar cells, is my understanding, and doesn't put them where they're not needed to produce energy. With that said, I'm skeptical of the Tesla product for a number of other reasons. We'll see if it works out. Others have failed at that kind of product.

Maybe Tesla should invent a turntable you place the house on so it can track the sun.
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Again, it's more economic to just make cheaper solar panels. If it costs you nothing to put solar panels on the bad side of the roof, then it's worth doing. ;) You really have to do the math in the market you're in and see if it's economic. A few years ago I would have made the same comments as you. When our sales reps started using more north facing azimuths in the last couple years, at first I admonished them and did a lot of checking of their numbers. But as we dropped prices farther and farther, the numbers kept checking out. When you have lower roof pitches and higher electric bills, there's nothing dumb about it.
 
JFletcher said:
As to the topic question, PV systems only make financial sense to me if you are living way off of where power is and have to pay for the POCO to bring power to you, POCO power is extremely expensive or unreliable, or possibly RVs or prepper-type situations. I've a friend in NV who lives on solar, not for any environmental reasons or tax breaks, but because it would have cost him somewhere north of $200k to get POCO power there.
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If you are talking about off grid systems, I'll agree with you. People with reliable grid power who just want to "get off the grid" haven't run the numbers. Off grid power, all in, with PV and batteries is still ~10X what grid power costs. If you are talking about grid tied systems designed to offset the cost of energy from a POCO, however, that's another matter entirely.

JFletcher said:
I do find a lot of PV systems, especially small, turn-key ones, large on possibility and short on reality. I saw an ad not too long ago for a 'solar generator', and it showed the unit running a TV, lights, even a dishwasher and washing machine. What was in the fine print was that to run that washer, it would require several additional panels (not included in the base cost) as well as extra batteries.
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There is misrepresentation in the PV industry, just like everywhere else. That's not at all typical.
 
ggunn said:
... Off grid power, all in, with PV and batteries is still ~10X what grid power costs. ....
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Er, I think it's gotten a lot better. I'd say 3-4X national average, 1.5-2X California, and nearly break even in Hawaii. Not to disagree with your conclusions though.
 
I'm not averse to renewable Solar, wind, wave etc.
These don't come cheap and are variable sources. I read a paper - I think it was from Universiteit Leuven in Belgium - that suggested that about 15% was the maximum from variable sources. Specifically wind. Above that you needed "spinning reserve" from conventional sources. I'm sure solar can reduce your energy bill - after you have financed the installation costs.
And that doesn't factor in the variable contribution. It would need storage at utility level to level out the peaks and troughs and we don't yet have that at an affordable lever.

One technology that does cut the mustard in that respect is hydro. Itaipu, Three Gorges are examples. All that water behind the dam is stored energy.
 
Besoeker said:
I'm not averse to renewable Solar, wind, wave etc.
These don't come cheap and are variable sources. I read a paper - I think it was from Universiteit Leuven in Belgium - that suggested that about 15% was the maximum from variable sources. Specifically wind. Above that you needed "spinning reserve" from conventional sources. I'm sure solar can reduce your energy bill - after you have financed the installation costs.
And that doesn't factor in the variable contribution. It would need storage at utility level to level out the peaks and troughs and we don't yet have that at an affordable lever.

One technology that does cut the mustard in that respect is hydro. Itaipu, Three Gorges are examples. All that water behind the dam is stored energy.
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Yes, the great energy storage problem. Here in NY at the Robert Moss Niagara hydro plant, they also pump water uphill at off peak times for storage - 600,000 gallong per second wikipedia says!
 
Coppersmith said:
The roofs still seem to be pointing the wrong way. Maybe Tesla should invent a turntable you place the house on so it can track the sun.
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Edison beat him to it. This is the Black Maria the worlds first movie production studio. The roof folded back and it was on tracks to spin and follow the sun.

 
MAC702 said:
Hadn't thought about the roof replacement cycle wanting to correspond with the PV replacement. Here, I think we WANT them on the roof if we can, because, hey, that's a lot less sunshine hitting the roof and heating the house.
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It wouldn’t be the light from the sun that would bother me if I lived in your area......

Close-Encounters-Third-Kind-FTR.jpg

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regarding the direction that the solar panels point:

Pointing solar panels in the wrong way reduces their output and makes them more expensive per kWh produced. However since the sunlight itself is free, you don't care about the reduced efficiency; all you care about is the increased capital cost for the panels. If the increased cost of the panels is less than the cost increase for aiming the panels correctly or using a sun tracker, then you are better off with simpler installation allocating more expense to the panels but avoiding the cost of additional support structure or sun trackers.

IMHO getting to the real question of the economics of solar power must of necessity be a political discussion. Perhaps MH and the moderators can come up with a suitable forum for this discussion, since it is 'electrically related politics'. Currently residential solar is economically viable only because of a bunch of artificial incentives, including tax credits and things like net metering tariffs. There are good arguments both for and against these incentives, and discussion of such can get quite heated.

-Jon
 
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