Two of the most popular policy models administered to stimulate the deployment of solar energy are Renewable Portfolio Standards (RPS) and Feed-in-Tariffs (FITs).

RPS programs with a solar carve-out define a set percentage of electricity that each utility or energy supplier must procure from solar energy generators. To comply, an energy supplier can develop its own solar projects, or procure Solar Renewable Energy Credits (SRECs) from SREC aggregators or individual solar energy system owners.

In contrast, a FIT is a solar energy subscription program in which a solar energy owner can sell their electricity at a premium to the government or regulated energy suppliers. The solar electricity premiums, like the one in Ontario, Canada can be very lucrative. The stable cash flow from a state body minimizes the risk for the financier. The returns are defined for a 20-year period, the O&M costs of the facility are typically very low, and the project developer can seek financing with the FIT contract in hand.

These two policy models share similar objectives; they accelerate the deployment of solar energy technologies, build economies of scale that reduce technology costs, and carve out a space for solar within the electricity market. Both models also have unique strengths and proven track records of creating exponential growth in solar energy markets.

In some circles, FITs are held as the gold standard in stimulating solar development, while RPS programs are held in a lesser regard. Advocates of FITs can point to solar success stories like Germany and Ontario, Canada and like to discuss how a FIT could be effectively administered in America. Yet, these discussions are premised on the assumption that FITs are better for solar than an RPS. In an attempt to reframe these discussions, we would challenge this assumption and suggest that, in the mid-term and long-term, an RPS program is a more sophisticated policy instrument which is capable of creating a healthier and sustainable solar market.

The fundamental difference between the two models is that an RPS is a self-correcting model based on incentivizing individuals through secondary markets, while a FIT is a subscription program that sustains a solar market to the extent that governments continually allocate sufficient funds or political will. FITs allow solar developers to secure long term financing for solar development, but they do not create an incentive structure which encourages developers to continually reduce costs. An RPS program, as compared to a FIT, does not provide such security. In states with an RPS and an SREC market, system owners recoup their investment through the Investment Tax Credit (ITC), local rebates or incentives, and through the sale of SRECs.

While the ITC and state rebates tend to be reliable, the value of SRECs on the spot market can fluctuate dramatically over short periods of time. This spot market variability thus creates risk for the system owner and financier. And, if we were to stop the analysis here, it might seem clear that FITs are better for solar energy than an RPS. However, this conclusion would overlook the mid-term and long-term growth of solar markets in favor of robust short-term growth (and it would also ignore the fact that system owners can lock into multi-year guaranteed rate SREC contracts).

In fact, one should recognize that the price fluctuations in SREC markets are a result of supply and demand, and are part of the way that RPS markets adjust themselves. The supply is set by the amount of solar energy installed, and the demand is defined by the compliance requirements as established in the RPS. In the event a solar market witnesses exponential growth in solar development and SREC supply outpaces growth in demand, prices will be pushed down for SRECs.

And, to be clear, this is the goal of both an RPS program and a FIT: drive economies of scale and create a competitive market for solar technologies. If prices are pushed downwards in SREC markets, system developers will be incentivized to reduce the costs of the development in order to maintain margins. In the event prices are too low, the supply of SRECs will be short, energy suppliers will be required to pay higher prices for SRECs, and the market will receive the stimulus needed to push development forward again.

In a state with an RPS program and a robust SREC market, the winners will be those that can stay ahead of the curve in developing systems at lower and lower costs compared to other developers. The losers will be those that continually lag in developing systems at lower costs compared to other developers in the market. In so doing, an RPS program creates competition in the market that will ultimately drive down the costs of solar energy and make it more affordable for more people.

FITs, on the other hand, do not create the same sort of competition between developers to reduce costs. Depending on the FIT premium and the payment schedule, developers can maintain strong margins whilst making no investments in efficiency. The result is FITs can become oversubscribed, burn through allocated funds, and then come to a halt because the market never weans itself off of the crutches of government support. Because of the amount of capital required to fund these programs, FITS are also subject to political scrutiny, and if political change occurs, it can wipe a market out almost overnight (i.e. Spain).

For all these reasons, we would conclude that short-term FITs can create spectacular growth in solar markets, but are less sustainable compared to an RPS program which can adjust to the basic laws of supply and demand.

About Sol Systems:
Sol Systems is a Washington D.C. based solar finance and development firm that is committed to making solar energy more affordable. We enable homeowners, businesses, and solar developers to finance their solar energy systems by providing a conduit for solar renewable energy credit (SREC) monetization and long-term price stability. With more than 1,200 customers across 13 states, Sol Systems has become a critical player in developing SREC markets and financing solar energy systems. We are proud to be the oldest, most sophisticated, and largest SREC aggregator in the country.