Affordable solar: It's closer than you think

[n2doc]

December 1, 2011 By Marcia Goodrich

It's time to stop thinking of solar energy as a boutique source of power, says Joshua Pearce.

Sure, solar only generates about 1 percent of the electricity in the US. But that will change in a few years, says Pearce, an associate professor of electrical engineering and materials science at Michigan Technological University. The ultimate in renewable energy is about to go mainstream.

It's a matter of economics. A new analysis by Pearce and his colleagues at Queen's University in Kingston, Ontario, shows that solar photovoltaic systems are very close to achieving the tipping point: they can make electricity that's as cheap—sometimes cheaper—as what consumers pay their utilities.

Here's why. First, the price of solar panels has plummeted. "Since 2009, the cost has dropped 70 percent," says Pearce. But more than that, the assumptions used in previous studies have not given solar an even break.

"Historically, when comparing the economics of solar and conventional energy, people have been very conservative," says Pearce.

more

http://www.physorg.com/news/2011-12-solar-closer.html

[rfranklin]

1. We need more fracking!

Much cleaner than solar energy!

[dtexdem]

3. We need more fracking solar energy ...

and less fracking natural gas.

[Exultant Democracy]

2. Thank you China, I wish we were the onse leading this but at least someone is.

[jwirr]

4. If it has to be that way at least we are doing something.

[pscot]

5. amazon is seling bare panels

for as low as $2.80 per watt. Kits run about $5/watt. Adding additional panels should bring the $/watt down. Installation adds a bunch though.

[DCKit]

6. Yeah, you can't get the rebates or tax incentives unless you use a licensed installer.

Still, $5/watt installed is a third of what we paid ten years ago.

[roody]

9. Can't you be a self installer? You can with PGE---

with solar hot water anyway.

[txlibdem]

11. Solar hot water is just pipes + a tank + a pump, very simple to DIY

The real question is can you install everything yourself *except* plugging in all of the connections (which has to be done by a licensed electrician).

[tinrobot]

14. Solar power is just panels, wires, and an inverter.

[txlibdem]

20. The difference being that you need a licensed solar installer or licensed electrician for solar PV

If your state requires a solar installer then you will not see the benefits of going solar... except the good feeling of knowing that you are no longer part of the carbon death spiral problem. Most people want the cost of solar to come down to half of what it is now so they can reap the financial benefits as well.

If you live in a state where you can do most of the solar installation except the electrical connections (which a licensed electrician has to do) then you are lucky and you'll see payback from your solar panels a decade earlier.

[DCKit]

15. I don't know how anal they are with the regulations.

Just wanted to make sure that everyone is aware of that one caveat.

A professional install could conceivably cost as much as the equipment. If it's mandatory, there go the tax savings.

[Bob Wallace]

7. Solar panel prices low, low, low....

Backwoods Solar (good company I've done business with) has panels for $1.60/watt.

Solarbuzz, a solar information company, lists lowest retail prices for thin film at $1.25/watt and lowest silicon retail $1.28/watt.

Sun Electric (haven't done business with them but their reputation is good) has panels for $1.28/watt and possibly lower. I think Sun sells a lot of overstock. I know they sold the leftover Evergreen panels after that company went bankrupt so they are probably below what Solarbuzz would consider 'normal retail'.

Sun is offering grid tie packages (inverter, hookup cables, everything but mounting racks) for as little as $1.88/watt. Mounting racks are not included because there's some variation between different installations, but they have good rack prices as well. They're including quality inverters in their packages.

Apparently China is shipping PV at $1.15/watt wholesale and someone is selling very large quantity for under $1/watt according to GreenTechMedia.

Solar has gotten very affordable. Look for huge increases in rate of installation.

Installation should add $1 to $2/watt. Less if you mount the panels yourself.

[roody]

8. My solar system cost less than my car.

It is a matter of priorities.

[txlibdem]

10. And why does everyone say that "solar panels last 20 years"

They will gradually produce less and less electrical energy so that, at their 20th birthday, they will produce either 90% (the expensive panels) or 80% (the cheap panels) of their original output. They don't dry up and blow away or melt into a pile of goo. They just make a little less power than they did the day you bought them.

So what? Just buy a couple more panels at year 10 and a couple more at year 20 and you're back to the original output. And there's a good chance that you won't be using as much electricity in 20 years anyway: Energy Star has finally hit the consumer electronics industry and they are producing better, faster products that also use LESS power. And if your home is as drafty and energy inefficient 20 years from now as it is today then there's something wrong.

The solar payback? If you live in one of the areas where there are dozens of solar installer companies who feel they have to compete for your business then you will achieve payback within 10 years. If you live here in Texas or other areas where solar installer companies are few then you're looking at closer to 17 years for payback.

The shortcut? Solar Leasing companies are more predominant here in Dallas than Solar Installers. They will buy the panels and all ancillary parts and equipment and install them on your roof for free. You pay the same amount for electricity as you do now but you pay it to the solar leasing company. In years to come, when your neighbors' electricity rates have gone up yours will stay the same.

Note: some solar leasing companies charge you in a different way, so do your homework before signing on the dotted line. Some will raise your rate in the future but less than the electric utility has raised their rates so you get a middle of the road solution. I don't see the business sense in doing that because they're making a profit from day one anyway. Caveat Emptor.

My final take: if you have the money to buy a full system that provides you with all your energy needs then go ahead and do it. If you are of more modest means then just put up a smaller solar array but make sure that the inverter and controller can handle much more than needed so you can add panels as you are able. And don't forget that solar panel prices will continue to decrease in the coming years so you'll likely be able to afford to add more later on than you think.

[Bob Wallace]

12. Good points...

And if you start with a smaller number of panels make sure the installer runs large enough wire from panels to inverter to handle your future array.

After the initial installation you can add the other panels yourself or get a handyman type to do it. It's pretty much tinker-toy work.

BTW, if you assume a 0.5% loss per year you'll have 91% output at 20 years and 78% output at 50 years.

I've seen reports of current panels dropping only 0.1% to 0.2% per year. If that holds then you should have 91% output after 50 years.

There's nothing to wear out with silicon solar panels. They are basically a thin sheet of rock protected by a glass cover. The weak spot seems to be connectors and those are much better designed than what was used 40 years ago.

[txlibdem]

21. Thanks, and welcome to DU!

I think the cheaper panels quote 80% at 20 years. But even given that, all you have to do is add a couple of panels at the 10 year point and another few at the 20 year point. No biggie.

You hit the nail on the head that one needs to make sure you start out with a system that has room to grow. It will cost only a bit more but will save you big money in the long run.

I feel that if people make it a priority they can add one panel every year, maybe even two. Pretty soon they will be making most if not all of their own power.

[kristopher]

13. The only person who repeated that canard is you.

National Renewable Energy Lab uses 30 years as a baseline for the normal life of solar panels and they expect useful production as you describe well beyond 40 years.

Since no one else at the OP article or on this thread has made a peep about 20 years, it is a weird thing for you to pop out with. It's more like you are trying to plant the idea rather than refute it.

[Bob Wallace]

16. Still 97% after 21 years...

Here's a study published in 2003. I've found nothing on line that says that these now 30 year old panels have been taken down...

"The study of the 10 kW TISO plant enabled to verify the good reliability of Arco Solar ASI 16-2300 modules.
Although these modules are not manufactured anymore, the fact that after 21 years of outdoor exposure they are
still working in a very satisfactory manner (97% of initial power and 6 modules not working anymore) contributes
to strengthen the credibility of photovoltaic technology as alternative energy resource."

http://www.isaac.supsi.ch/isaac/pubblicazioni/Fotovoltaico/Final%20Report/rapporto%20finale%20-%20progetto%20eu%205fp%20-%20mean%20time%20before%20failure%20(mtbf)%202003.pdf

I have some personal experience with Arco panels. In about 1992 I bought 400 watts of Arcos which had been used with focusing lenses to see how they would function with '>1 Sun'. The extra input had turned them brown but had not lowered their output. Twenty years later those 'brownies' are still performing close to factory specs.

[kristopher]

18. That's the system I read about at NREL

Thanks for the details. NREL uses the 30 year benchmark for calculating energy paybay and net production. However it is as you say; as the systems prove their longevity it will justify amortizing both the energy and monetary costs over a longer period. {Although realistically the business case will always be based on less than 20 years.)

[Bob Wallace]

17. "People say..."

I commonly see people report "20 years".

I think it comes from two places.

First, 20 year guarantees are somewhat common. Sometimes one sees 25. I can see how people get from a 20 year guarantee to a 20 year lifetime if they aren't thinking carefully. But they should remember that a 30,000 mile guarantee is pretty common for cars that we expect to be fairly trouble free for 100,000 miles.

Second, LCOE (levelized cost of electricity) is generally calculated with a 20 year loan as a standard. People get in the habit of talking about the 20 year price of power from various sources.

Spinning off that, I'm on a kick to get people to start taking about lifetime cost of power from solar (and other generation methods).

Let's assume $3.50/watt installed, 20 year financing at 5% and a 5.5 avg. hour solar day and $0.01/kWh operating and maintenance cost. LCOE for that 20 year period would be $0.148/kWh.

But at the end of the 20 year loan payoff let's assume the panels are going to last another 20 years while losing 0.5% per year in output. Spread the capital and financing over 40 years and the price of electricity drops to $0.086/kWh.

Assume 50 years and the average price over all years is $0.072/kWh.

Since the payback is during that initial 20 years we're really looking at some decades of almost free power from solar.

[txlibdem]

19. That was the point of my post: solar panels won't just stop working at 20 years

They will have a much, much longer life than some people think.