Image of solar field.

An array of hundreds of solar panels stretching 540 feet along an Oregon highway is helping to power a nearby interchange with clean, renewable energy through a unique public-private partnership that could serve as a model for the nation.

Oregon’s “Solar Highway Project” sits at the interchange of Interstates 5 and 205 in Tualatin, Ore., at the south end of the Portland metropolitan area. The project is the nation’s first roadside solar photovoltaic demonstration project.

According to the Oregon Department of Transportation, the project’s 594 solar panels produce about 122,000 kilowatt hours annually. The panels produce energy during the day which is used to light the interchange at night. ODOT buys the energy produced by the array at the same rate the agency pays for regular energy from the grid.

This clean, renewable source of energy will help the agency meet the mandate from Oregon Gov. Ted Kulongoski that state agencies obtain all of their electricity from renewable sources. By replacing energy from the grid, the solar electricity produced by the project will avoid the production of nearly 43 metric tons of carbon dioxide equivalent emissions each year.

The $1.28 million project, which has been in operation for just over one year, was developed through an innovative public-private partnership between ODOT; Portland General Electric (PGE), Oregon’s largest utility; and US Bank. Material providers included Solar World US, the nation’s largest solar panel manufacturer, and PV Powered, the nation’s largest inverter manufacturer.

Making the Most of the ‘Right-of-Way Asset.’

ODOT Project Director Allison Hamilton explained that under this unique partnership “the public gets multiple values out of its right-of-way asset.”

“Using state and federal tax credits, the renewable energy projects are developed at least possible cost, which benefits the utility rate payers – including ODOT and the State of Oregon, “ Hamilton said. At the same time, ODOT gets green energy at grid rate instead of the higher green energy rate, she added.

“The solar energy project is owned, operated and maintained by the utility, which also assumes all the risk, and is responsible for maintenance of the right of way for the term of the contract (from 25 years up to 40 years or more),” Hamilton explained. But the utility also gets to count the project towards its renewable energy portfolio requirements, she said.

“It’s a win-win-win business model,” Hamilton added.

ODOT officials and PGE officials have deemed the project a success, demonstrating that solar arrays can complement and not compromise the transportation system.

In fact, Hamilton said the project has exceeded expectations, producing more than the expected 112,000 kilowatt hours in its first year, with only one maintenance incident where a panel was cracked and had to be replaced.

As a result, Oregon DOT and its partners – utility providers and private businesses – are poised to expand production of solar energy at the demonstration site and as well as other locations in the state.

Third Party Financing Model

According to ODOT, these public-private partnerships are expected to follow the same type of third-party financing model developed for the demonstration project.

“The utilities would contract with solar developers to design, build and install the arrays, which they – the utilities or limited liability companies involving the utilities – would own, operate and maintain, and which could count towards meeting statutory requirements to develop renewable energy resources. The utilities would also be responsible for maintenance and successful operation of the arrays, including any damage due to vandalism or crashes,” according to a summary on the demonstration project website.

ODOT would have a 25-year agreement to purchase all electricity generated by the solar projects, with options to renew for up to three five-year extensions.

DOTs Urged to Work with Utilities

Hamilton said many other states have expressed interest in following Oregon’s lead, but she stressed that each state will have unique circumstances. “Because each state has its own utility regulations, I would recommend project proponents work with or through their utility to learn the most efficient and cost effective way to size, permit and connect a project, and also to determine the most advantageous financing and ownership model,” she said.

“We learned that the larger the installation, the better, as you are able to spread your fixed costs out over more kilowatts, bringing down the cost per installed kilowatt” compared to the cost of existing grid energy.

Hamilton urged transportation agencies that are interested in developing a solar highway project to take advantage of the expertise of the utility, whose core business is energy generation.

“Oregon’s state transportation system has nearly 19,000 lane miles of right-of-way and there are more than 8 million lane miles of right-of-way across the nation,” according to an ODOT project summary. “Solar arrays on less than 1 percent of Oregon’s right-of-way could supply the nearly 50 million kilowatt hours needed annually by the state transportation system,” the agency said.

The project has been recognized with numerous honors, including the Federal Highway Administration’s 2009 Environmental Excellence Awards.

A wide range of information is available on the project website, including a solar highway meter that tracks energy generated on-site, news releases, photos, videos, research, technical documents, and information on planning for future projects. Additional information also is available by contacting Allison Hamilton at [email protected].