So they lose 6-7 cents for every KWH they buy from her? Do they make the loss up in volume?
Did others get the show with Descriptive Video Service?
“Grey haired couple walk on lawn” “sparks emit in diagram of solar panel” “Young boy rides toy tractor”
Brian
You know, the more you spend the more you save.
I would guess that they don’t buy all that much electricity from residential producers and the prices they pay are likely determined by the state PUC.
I think that needs clarification. She may be getting a check for $40 but also paying for her electricity in a separate transaction. Most houses don’t have enough surface area to create a zero sum energy footprint. Unless she has a battery storage system she must buy electricity on shady days and also at night. The payoff calculation probably doesn’t take into consideration the time value of money so I’m going to challenge the 25-year payoff. At 6% interest rate a loan will double in cost over 25 years.
What hasn’t been discussed is the environmental disaster solar cells become over time. They have a cycle duty time of approx 40 years. After that you have a huge landfill issue.
Solar cells are not cost effective. That doesn’t mean they aren’t warranted if that cost is offset somewhere else but you have to add up all the costs including environmental. Think of all the short term manufacturing that goes into making individual power stations (which is what we’re talking about). If you do that to every house then it will all have to be replaced over time. Power stations do not suffer from a 40 year duty-cycle.
There are at least 4 issues involved with this discussion:
- reliance on foreign energy (security)
- global warming
- environmental damage
- the cost of power
It’s difficult to calculate security issues. If you take money from a country with high unemployment (pick one) does it become more or less of a threat?
Global warming is also hard to calculate. Particularly if money is applied to eliminate perceived causes instead of repairing known damages.
Environment damage should compare the cost of cleanup against the cost of prevention or containment.
The cost of power drives all other costs because a savings is a financial offset that can be used in other areas of the equation.
I know several people who are net power producers and get a monthly check from their electric utility, and no they don’t also pay, it is the net difference, and they only have one meter, it spins both ways. Normal roof area is enough, actually just the south side of the roof.
And they don’t use batteries, but actually use the grid as a battery of sorts, they sell power to the utility whenever they make more then they uses and buy it back when they need more.
No, you don’t know several people who are net power produces using the roof of their house. It’s not physically possible.
It IS possible to subsidize the lopsided transfer of power by paying more for daylight power and selling it back at night for less. You can subsidize anything but that doesn’t make it productive.
So how much photovoltaic power can be generated on one average day from 1 square foot of south-facing roof at a 30 degree pitch from horizontal from, say 45 degrees latitude in the summer? Winter?
I have a south-facing roof with minimal tree shading. I use 25 KWH per day for my household, average year-round. If I could generate 25KWH per day, I’d have a net cost and income of zero for electricity, and only the capital cost to consider. So how big would my roof area have to be?
. Depends where you live but if you have 12 hrs of sunlight then probably close to 400 sq feet of roof. An off-grid system (with batteries) would run about $20K. If you treated it like a 5 year car loan then the interest would not consume the life of the unit.
I’m basing my earlier statement on the claims made by the vendors and also statements made by owners of solar cells on the PBS documentary April 24 2007.
It’s not that I’m against solar cells but I think the money could be better spent on research. I think the best use of our energy dollars should be spent on nuclear power for the short term.
That isn’t really a subsidy, daylight power is worth considerably more, generally, than nighttime power. The subsidy is simply that the power companies pay more for the solar power during the day than whathey would have to pay from traditional energy sources at the same time.
I could swear I posted a reply and it was accepted, then the Capybaras ate it. Oh, well, I’ll try again.
You don’t need batteries if the grid is your backup. We’re getting into the broadest of estimate territory, here, I know, but maybe a smaller photovoltaic system without batts could be had for $10K?
And my roof wouldn’t be big enough for 400 sq ft of panels on the south side, maybe only 250. So doing some rough calcs, including all relevant costs, I would be paying about $50 MORE per month for the privilege of having solar power on my roof.
The only thing I did not take into account was the “we’re saving the planet” benefits.
So, no, it would not be cost-effective at this time.
Well… Ok… that would be a subsidy. It’s OK, you can say the word, it’s not bad. Solar gooooood. coal baaaad. It’s just that coal is a lot cheaper. I’d rather pay slightly more in taxes (slightly being the operative word) and invest it in research. In the short term we should build less polluting/cost efficient plants (cough-nuclear). The alternative is a huge landfill problem with the current solar power technology. I suspect the thin film SP technology will drastically reduce the cost of panels and the amount of end-of-cycle trash.
I don’t disagree with you, I was just pointing out tha solar, like all other sources of energy can command a higher price during the day because that is when it is most valuable.
You also need to take into account the tax benefits. You would get a federal tax credit for making your home more energy efficient, and you may get a state credit. It depends on your state. You may also be able to sell power to the grid during the day, when you’re not using the power (if you get a timed thermostat Una mentioned above.) You still may not save money, but you shouldn’t lose as much money.
At any rate, a timed or programmable thermostat will definitely make a dent on your energy bill.
Maybe I didn’t make that clear, but my rough calcs included the rebate from selling power back to the grid. Basically, my roof area, the latitude, the fact that the sun wouldn’t shine continuously or even every day, balanced with my typical household use would produce, on balance, less energy than it used.
No need for anything timed. I drop the house temp at night in the winter because I like to sleep under blankets as well as save money. Since I don’t go to bed or get up at the same time two days in a row, an automatic thermostat is not convenient, and a manual one works perfectly.
Meanwhile, here is an interesting article on a different kind of solar power development. This one claims to generate electric power for 3 times the cost from other sources, but the “cost will come down over time.” Where have we heard this before?
Well, don’t we also have the problem of economies of scale? I mean, Quebecers enjoy fabulously low energy costs by virtue of our profusion of hydroelectricity, but I doubt it would be cost-effective for me personally to go out and find a nice river to dam to provide one household’s worth of electricity – certainly nowhere near as cost-effective as simply buying my power from the ginormous power dam someone courteously built for me on La Grande Rivière. Surely solar energy would be more cost-effective if we were discussing large-scale power plants rather than rooftop panels.
Like my solar energy course described above, a smaller installation may pay for more than itself while a larger one would crate debt.
matt_mcl, I’m not sure that economies of scale apply to solar photovoltaic power in the same way that they do to other forms of power generation.
AIUI, the basis of all solar photovoltaic power schemes is the solar cell, which converts the solar energy interacting with a small (say for sake of argument 1 cm[sup]2[/sup]) indvidual cell. The cell produces a minute amount of power, that when linked with an array of similar similar cells, produces an aggregate of power that can be used. This format means that there’s actually a loss in efficiency, simply from transfer losses in a larger unit compared to the smaller individual cells. This is in direct contravention to how efficiency of larger power plants generally improves compared to a smaller power plant with any other power generation schema I know.
Kohls goes solar.
If big box stores were all doing what Kohls is doing I wonder if there’d be an affect on the overall availibility and cost of solar panels for the average Joe or average business for that matter.