Unlike other sources of electricity, solar is a type of power that is flexible enough to fit into many kinds of spaces, from a sloping roof on a home to a field in the middle of the desert. The latest novel example of this is so-called “solar community garden,” which are solar systems that are community-owned and shared.
Community solar gardens ideally are located within a town or city limit and serve a bunch of residents who either pay to own a piece of it or subscribe to the project without owning the equipment. Electricity from the solar panels goes to the grid and is sold to the local utility, which then credits the sale to the owners or subscribers of the solar garden. The credits then show up on each of their utility bills.
The goal is to allow renters, or anyone who doesn’t or can’t put solar on their rooftops, to still benefit from localized solar electricity generation, which is encouraged by federal and many state governments through rebate and tax incentive programs.
“We think of it as owning a garden plot in a family solar farm,” said Matt Cheney, CEO of CleanPath Ventures, at the Intersolar conference in San Francisco last week.
What are the barriers?
A community solar garden isn’t common because many states and utilities don’t have policies in place that allow such communal ownership and credit-sharing of a solar system. What is more common is net metering, where a home or business owner can put solar on their roofs and sell any excess electricity at retail rates to their utilities. The sale shows up as credits on their utility bills. Net metering rules often tie the solar equipment to a particular utility customer’s account, so there is no sharing of the credits.
California is working on expanding net metering to renters who don’t own roof space for solar panels. Called virtual net metering, these tenants of residential or business complexes can share the credits from the sale of electricity from a single solar installation. Landlords also will be able to share the credits because they, too, are electric ratepayers on the premises (they pay for electricity that lights up the garage, hallways and other parts of the complex).
But virtual net metering requires that the installation has to be located on the premise. Not every rooftop has the space to accommodate solar panels. And landlords may not see enough incentives for them to bother with a solar system construction on their properties.
In contrast a community solar garden could be located elsewhere and on the ground instead of rooftop, and it could allow for a transferring ownership or subscription. It also should be cheaper to install because it’s likely to be larger than a typical residential rooftop system.
“You can sell that on Craigslist,” Cheney said. “You can give your friends a wedding gift of 250-kilowatt of solar capacity.”
Potential change in California law
Cheney used his talk at Intersolar to tout the California Senate bill, SB 843, that would make community solar gardens possible. The bill has made its way to the state Assembly and is waiting for its first hearing.
One of the discussions about the bill deals with how much community solar development owners or subscribers would get from selling electricity to their utilities, said Peter Olmsted, a policy advocate for Vote Solar, an advocacy group in San Francisco. Currently, the bill wouldn’t provide retail rates for the electricity sale, Olmsted said. The idea is that if you aren’t paying for the full distribution cost of bringing electricity to your home, then you aren’t entitled to get paid to offset that cost.
“We are trying to get our arms around how this would actually play out and if it’s going to create an attractive program for a broader community,” Olmsted said.
Political leaders in California and other states have touted small-scale solar generation as an important element of their plans to gradually replace power from coal or natural gas and cut greenhouse gas emissions. Installing smaller solar projects, that can be installed within urban or suburban areas, makes it unnecessary to build expensive transmission lines to ferry solar electricity from remote regions. Some solar power advocates also want more of this type of power projects instead of solar farms that require a large swath of land and often spark opposition from environmental groups.
Although community solar garden is a good idea, implementing it may not be so easy. There is still the issue of land availability – properties in large cities could be pricy, making a solar project economically unfeasible. What is the minimum size of a piece of solar system that a resident must pay for or subscribe to? If the minimum is set too high, then some people may not be able to afford it. Can people take their stake in the community solar garden when they move out of town?
Community solar gardens already are popping up in some places in the country. Two in Colorado have gotten some press coverage, including this 858 KW system that serves 350 people. The state passed a community solar garden bill last year. A Colorado congressman, Mike Udall, also has introduced a bill that would entitle community solar garden owners to take advantage of a 30 percent investment tax credit.