Wednesday, May 13, 2009

Solar Sucks

Everyone knows photovoltaic solar panels suck. They're inefficient, expensive and impractical. They indirectly increase green house gases and energy usage by diverting money that should go to insulation and other conservation improvements.
All for a teeny tiny teeny little few watts.

I had hope for solar water heating though. It is much more efficient than photovoltaic solar electricty. But...

Turns out even solar hot water sucks. From all the propaganda and junk about getting water up to 160F or higher (even here - Portland fall days ), I thought maybe solar "thermal" (that's what they call it, Solar Thermal) would be a reasonable idea.


It costs about $2100 to get a panel (which weighs 200 lbs and measures 4x10') that will produce 10,000 btu on a cloudy day (40,000 on a nice summer warm summer day).
10,000 BTU

For reference, in gas terms, 100,000 BTU = 1 Therm.
NW Nat sells one therm of natural gas for $1.29

So TEN DAYS (regular portland cloudy days) of production from a $10,000 of panels would produce about $1.29 of equivalent gas water heating.
Or about $50/year, rounding up a little for furnace inefficiency. Wow. $50/10,000 = half a percent return. Actually not even that. The panels don't last forever...

Some different calculations get it up to 2%. Still sucks. After incentives? Maybe.
The whole thing just sucks.
And, I haven't even figured in the cost of the storage tank & heat exchanger system and other plumbing.

It's mind boggling that PV is so popular and even lower efficiency.

Of course, energy costs could go up. Also, that 3-4% return isn't real because (at best) that solar thermal system will last 30 years.
Your roof won't last that long. Also maintenance costs will eat into it. You're never going to recoup your costs anything like your costs.

I was really hopeful we could use Solar to reduce energy expenses. Insulation gives far far better return (even wall insulation).

ALL THAT SAID: With Federal Credits and Energy Trust money, maybe you can make a profit on the solar Thermal systems.
50% BETC (or RETC) tax credit - uncapped now, I think - even for residential.
About 15% from the Energy Trust straight cash incentive (taxed)
+30% Federal Tax credit.
You've got enough of your costs covered so you will eventually possibly do OK.

It's a better deal for businesses, because they get to depreciate the full cost of the system.
That's worth about another 32%, so you are over 100%.

Free Panels! And you get to feel good about yourself because the $10,000 in incentives (you paid for with taxes) is buying you $50 worth of warm water every year.
Take that OPEC.
It's just not time for Solar yet.
It's time for efficiency and conservation. Not as hip, but much smarter.



Anonymous Anonymous said...

Solar sucks. Wind blows. Nuclear rules.

8/07/2009 10:40 PM  

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