What is the Renewables Portfolio Standard?

A Renewable Portfolio Standard (RPS) is a requirement that an electric power provider, i.e., a Utility, Co-Operative or Municipality, generate or purchase a specified percentage of the power it supplies/sells from renewable energy resources, and thereby guarantee a market for electricity generated from renewable energy resources.

Why a Renewables Portfolio Standard?


The Renewables Portfolio Standard (RPS) is a flexible, market-driven policy that can ensure that the public benefits of wind, solar, biomass, and geothermal energy continue to be recognized as electricity markets become more competitive. The policy ensures that a minimum amount of renewable energy is included in the portfolio of electricity resources serving a state or country, and -- by increasing the required amount over time -- the RPS can put the electricity industry on a path toward increasing sustainability. Because it is a market standard, the RPS relies almost entirely on the private market for its implementation. Market implementation will result in competition, efficiency and innovation that will deliver renewable energy at the lowest possible cost.

Current States with Renewable Portfolio Standards


How Would the RPS Work?


Renewable Energy Credits, or "Credits," are central to the RPS. A Credit is a tradable certificate of proof that one kWh of electricity has been generated by a renewable-fueled source. Credits are denominated in kilowatt-hours (kWh) and are a separate commodity from the power itself. The RPS requires all electricity generators (or electricity retailers, depending on policy design) to demonstrate, through ownership of Credits, that they have supported an amount of renewable energy generation equivalent to some percentage of their total annual kWh sales. For example, if the RPS is set at 5%, and a generator sells 100,000 kWhs in a given year, the generator would need to possess 5,000 Credits at the end of that year. Investors and generators make all decisions about how to comply, including: the type of renewable energy to acquire, which technologies to use, what renewable developers to do business with, what price to pay, and which contract terms to agree to. Generators decide for themselves whether to invest in renewable energy projects and generate their own Credits, enter into long-term contracts to purchase Credits or renewable power along with Credits, or simply to purchase Credits on the spot market. Only the bottom line is enforced: possession of a sufficient number of Credits at the end of each year. The Credit system provides compliance flexibility and avoids the need to "track electrons." Because the RPS applies equally to all generators, it is competitively-neutral.

What Is the Government's Role Under the RPS?


Government involvement would be limited to certifying Credits, monitoring compliance, and imposing penalties if necessary. The Credit certification process would apply to renewable producers who wish to certify their renewables output. Monitoring compliance would require each generator to demonstrate ownership of a sufficient number of Credits relative to electricity sales. For generators that are not in full compliance with the RPS at the end of the year, the administrative agency would assess an automatic penalty for each Credit that the generator fails to produce as required.

The amount of the penalty should be several times what it would have cost to purchase the Credits. A high penalty level makes the policy self-enforcing by avoiding the need to resort to costly administrative and enforcement measures. It is modeled after the federal SO2 allowance trading program, under which an automatic $2,000/ton penalty (indexed to inflation) is imposed for each excess ton of SO2 produced. Because of the high penalty associated with noncompliance, the EPA has not had to take any enforcement actions -- it is far more economic for power plants to comply than not.


What Are the Efficiency Advantages of the RPS Approach?


First, the RPS avoids the administrative dissemination of funds by government agencies, which can be bureaucratic and inefficient. In addition, government-administered programs almost always impose artificial constraints of various types, which increases costs.

Second, under the RPS, no renewable energy project is guaranteed a place in the market. Unlike a one-time competition for funds, each project must continually compete to keep its place in the market created by the standard. For example, existing projects and technologies must compete with new ones, and project enhancements must compete with greenfield projects.

Third, the certainty and stability of the renewables market created by a properly-designed RPS will enable long-term contracts and financing for the renewable power industry, which will, in turn, lower renewable power costs.

Fourth, least-cost compliance is encouraged through the flexibility provided to generators who are subject to the standard: they can compare the cost of owning a renewables facility to the cost of a Credit/renewable power purchase package and to secondary-market Credits. Those who are most efficient at generating renewable power will end up producing it, and those who cannot efficiently produce it will purchase Credits on the competitive market.

Finally, and perhaps most importantly, since large generation companies will be looking to improve their competitive position in the market, they will have an interest in driving down the cost of renewables to reduce their RPS compliance costs. They may do this by lending their own financial resources to a renewables project, by seeking out least-cost renewables applications, or by entering into long-term purchasing commitments. This fosters a "competitive dynamic" that is not achieved with policies that involve direct subsidies to renewable generators without involving the rest of the electric industry.