Offshore Wind: Costs and Considerations for Future Development

By Joni Sliger, Energy Fellow

A floating wind turbine near Portugal.
Credit: Senu Sirnivas / NREL

As I reported last week, offshore wind energy will soon be flowing to the residents of Block Island, Rhode Island. Yet some continue to question the costs of Block Island Wind Farm (BIWF): will this project benefit the electricity consumers as much as it benefits the industry?

Financing renewable energy projects is no small feat. Developers typically need to lock in a contract proving to stockholders and regulators that the investment will be recovered. In part, financial difficulties explain some of the failed offshore wind projects of the past, such as Oregon’s WindFloat Pacific. The WindFloat Pacific project would have created floating offshore wind turbines near Coos Bay, Oregon (where the ocean floor is too deep for anchored turbines like at BIWF). Competing with low electricity prices from cheap hydroelectric, however, the project was unable to secure a contract from a power purchaser. (Note though that hydroelectric power generation has its environmental problems and is not a guaranteed long-term electricity source.) Without such a contract and lacking regulatory approval, the Windfloat Pacific Project stalled.

At Block Island, BIWF did not have to compete with cheap hydroelectric power. Instead, the islanders rely on imported diesel fuel, costing about $0.50/kwh currently, or five times the average electricity rate in the U.S. of $0.10/kWh. Under BIWF’s contract with utility National Grid, rate-paying islanders’ current electricity prices will drop to $0.30/kWh. Mainlanders, in contrast, who receive the excess wind energy, will face above-market rates in order to finance the $440 project. But some continue to question whether the price difference for the islanders reflects the whole story and will truly result in greater savings for the islanders or the state. (For an inside look at some of the intricacies of ratemaking, you can read about one of the Public Utility Commission meetings discussing BIWF here.)

According to the Rhode Island Public Radio, the true value of BIWF will not be clear for several years. While analysts can consider the current price of diesel fuel (the island’s previous fuel source) and compare it to the contractual price for offshore wind energy, the price of diesel varies. Long-term price stability is one of many benefits of renewable energy sources. Renewables offer additional benefits as well, many of which have not historically been considered in ratemaking, such as lower emissions and greater independence from global markets. For example, consider this proposal to build offshore wind farms in order to mitigate hurricane damage by reducing wind speed at a projected net cost of...zero. Yet whatever the net cost of a project, it is the upfront cost that can be daunting to developers, utilities, and regulators.

Fortunately, according to a new study just published in Nature Energy, the cost of each type of wind energy (onshore, offshore, and offshore floating) is projected to drop substantially in the coming decades. From 2014 to 2030, experts project a 24-30% reduction in costs; by 2050, they project a total reduction of 35-41%. While future costs are difficult to predict with much accuracy, the study surveyed 163 experts, the largest elicitation study on energy ever conducted. 

In addition to rising market confidence and falling market prices, offshore wind also has the benefit of the federal government’s attention: the Department of Energy and Department of the Interior recently released the National Offshore Wind Strategy: Facilitating the Development of the Offshore Wind Industry in the United States. Calling offshore wind energy development a “significant opportunity” for the nation, the report identifies 34 actions for the DOE and DOI to take in order to “facilitate responsible, robust, and sustainable offshore wind development in the United States.” With supportive governance, competitive market prices, and visionary developers already taking the plunge into offshore wind development, offshore wind energy may soon be coming soon to a coast near you.