The Foreign Service Journal, July-August 2017

THE FOREIGN SERVICE JOURNAL | JULY-AUGUST 2017 37 the program in 2005, it was common to pay $10 to $12 per installed watt of solar power—including panels, invert- ers, wiring, installation and computer systems. At that price—two to three times higher than average U.S. electric- ity costs—systems were only financially profitable in locations where the host government provided a subsidy, where reliance on expensive diesel genera- tion was high—about $0.60 per kilowatt hour per year (kWh)—or where local utility-provided electricity costs were more than approximately $0.30/kWh. Our most recent systems are being designed and built closer to $3 to $5 per installed watt, thanks to advances Bring on the Solar: A How-To If you’re interested in bringing solar to your post, where do you start? Is there training available for local maintenance staff who might be put in charge of such a system? If you’re in a sunny location and paying more than $0.15 per kilowatt-hour for electricity, or rely on diesel generators for your electricity, reach out to OBO and we can see if solar power makes sense for you. The National Renewable Energy Laboratory, a laboratory of the U.S. Department of Energy, has some public guidance on best practices for solar power system operations and maintenance. Go to www.bit.ly/SolarBestPractices. What about solar for housing? Is the State Department considering adding solar to overseas housing? OBO makes renewable energy investments with the expectation of a positive return on that investment. In fact, the law (10 CFR 436) requires our return-on-investment (ROI) to be greater than 3 percent. Even in the best of cases, it takes a solar power project seven to 10 years to meet that ROI requirement. Given those financial constraints, two things complicate our ability to invest in renewable energy at our overseas housing. First, although there are exceptions to this, our residences often pay a lower unit cost for electricity than our office buildings. So the value of a renewable energy system at a residence is often lower than it would be just down the street at our embassy or consulate. Second, our housing supply is largely leased. We can’t justify the cost of installing a solar power system that will take 12 years to meet our financial requirements at a location that is only leased for five or 10 years. That being said, we are beginning to see cases where it does make financial sense to install renewable energy systems at housing that we own overseas. Chief-of-mission residences, deputy chief-of-mission residences and staff diplomatic residences are all starting to be evaluated for renewable energy deployment. The housing complex in Port-au-Prince, which is nearing completion, will include solar power. —Todd Evans 3TIER, INC. Figure 1. Global horizontal irradiance, or how much sunlight reaches the earth.