ADVERTISEMENT
Solar at Home

Solar at Home

The trials, tribulations and rewards of going solar

The power of negative thinking, aka net-metering

|

Editor's Note: Scientific American's George Musser will be chronicling his experiences installing solar panels in Solar at Home (formerly 60-Second Solar). Read his introduction here and see all posts here.

Our solar project has sunk back into its bureaucratic mire: We're still waiting on the state to come out and inspect the  array, so that the utility can install a new electronic meter and we can start to receive credit for any surplus electricity we generate and contribute to the grid -- a procedure known as net-metering. Paul Cronshaw of Santa Barbara, Calif., sent me a copy of his latest electric bill to show me what it looks like: his July, August, and September bills were negative and his October one was pocket change.

Net-metering greatly simplifies a solar project by eliminating the need for batteries to capture the surplus energy you produce by day for use by night. The electric grid does that job for you. The grid benefits, too, because solar arrays contribute power during peak-demand hours.

One common misconception about net-metering is that you can sell the utility as much power as you want. Sorry. The best you can do is to zero out your total consumption over the course of a year, which at least lets you squirrel away the power generated on long summer days for the dark winter. Any net annual production is a gift to the utility. So there's no point in building too large an array. Most state subsidies won't pay for an oversized system anyway.

The Network for New Energy Choices just published a report describing how many states still do not offer net-metering or make it onerously complicated for consumers. Texas is the most egregious holdout: a big, sunny, hot state like that should be a leader in solar power, but is held back by a lack of net-metering in most of the state. Even leaders such as New Jersey and Colorado have kinks to work out. (An earlier report by the same outfit recounted in gruesome detail the red tape that I and many other homeowners have had to endure.)

Cronshaw sent me his electric bill in response to my call for stories about solar installations. He reported that his 2.4-kilowatt system cost $21,540, of which $5,068 was covered by state subsidies and $4,942 by the Federal tax credit, for a net cost of $11,530. He, too, complained about how long the whole process took:

My solar installer did a great job mounting the system on my roof and handling the paperwork with building department and utility company. He has been installing PV systems since 1976.

The only problem that I encountered was having to wait nine months from start to finish.

The solar installation process needs to be sped up. It should be turn key operation, around two to three weeks. Also, we need to have a Feed-In-Tariff (FIT) program implemented nationwide. Other countries are way ahead of us on FITs.

Bottom line: I love solar! I think has potential to help a lot of people, our economy and our environment.

Many solar experts agree with Cronshaw about feed-in tariffs, an arrangement that decouples your production and consumption. You'd have separate electric meters for outgoing and incoming power, and you'd sell your power to the utility at a higher rate than you buy it for. In Gainesville, Fla., for example, the utility pays 32 cents per kW-hr for solar production, over three times the retail price of electricity. In Europe, the rate can be as high as $1 per kW-hr. Unlike net-metering, feed-in tariffs impose no limit to how much power you can sell.

In return, homeowners give up other subsidies such as tradable certificates (whose fluctuating value adds a huge element of risk to solar) and up-front cash rebates (which, because they scale up with the system size, can encourage installers to pack in as many panels as they can fit even if it compromises performance).

Frankly, though, I wonder whether this is any improvement. I prefer to have the cash up front rather than have to float the cost myself. Some solar experts, including the Network for New Energy Choice, argue that existing subsidies are already generous enough to make residential systems worthwhile. Utilities, for their part, complain about the added complexity of feed-in tariffs for homeowners. Where these tariffs shine is for larger installations.

I'd love to hear where other people stand on feed-in tariffs.

Update (December 8th, 2009): Steve Leppold of Eugene, Oregon, wrote to say that many utilities, including his, do pay for excess annual production. In Oregon, utilities pay for the excess at the retail electricity rate. Here in N.J., they pay at the lower wholesale rate. So net-metering provides at least this one benefit of feed-in tariffs.

Paul Cronshaw's electric bill, courtesy of Paul Cronshaw

 

The views expressed are those of the author and are not necessarily those of Scientific American.

Share this Article:

Comments

You must sign in or register as a ScientificAmerican.com member to submit a comment.

Email this Article

X