The Foreign Service Journal, July-August 2017

THE FOREIGN SERVICE JOURNAL | JULY-AUGUST 2017 39 sure all the wiring is neat and tidy, and none of the solar panels themselves are damaged. In West Africa, for example, panels have to be checked frequently because birds often pick up rocks or crustaceans and drop them on the panels. A few posts, such as Geneva and Managua, have contracts in place to have a specialist keep an eye on the equipment and perform preven- tive maintenance. Visual inspections aren’t always enough—the best way to tell if something’s up is by looking at the system output. All of OBO’s systems are equipped with a computer that tracks and shows their production. Every system gets weaker with age, but if you’re seeing a dramatic drop in production, it may be a sign that something like an individual solar panel or piece of electrical equipment has failed. Critical Components When people look at a solar power system, they generally look at the solar panels themselves and assume there’s some wiring voodoo that converts all of that sweet sunshine into electricity for our use. The biggest part of that “voodoo” is the inverter. These boxes turn the direct current electricity the solar panels generate into alternating current electricity. After the panels themselves, these boxes are the second place mainte- nance staff should look when they suspect a failure. Solar panels generally carry a 25-year power production warranty. Productivity varies, but even at the end of their life, you can expect them to generate 85 percent of the electricity that they did when they were new. Inverters, on the other hand, have a much shorter life. Inverters on systems built in the mid- to late- 2000s have warranties of about 10 years. As the technology has improved in recent years, though, it is becoming more common to see inverters with 15- to 20-year warranties. Mid-Life and End-of-Life As these systems age, facilities staff should regularly check that everything continues to operate effectively. When the sys- tem reaches 25 years of use, there are a few choices to consider. Do we leave the panels in place and continue to harvest what power is possible? Or should we invest in a new system that is more efficient and potentially less expensive than the one it is replacing? We’ll find out together as these systems start to reach the end of their useful and productive lives. n Solar panels cover a parking area at the U.S. consulate general in Curaçao. COURTESYOFCONGENCURAÇAO