Puerto Rico issues microgrid rules, gives PREPA 120 days to establish interconnection rules

Puerto Rico regulators take important steps to lay the groundwork for developing a microgrid industry as they issued final microgrid rules just five months after draft rules were released. The Puerto Rico Energy Commission issued the rules (CEPR-MI-2018-0001), ordering the utility PREPA to establish interconnection rules in 120 days. Until these rules are in place, only off-grid cooperative or personal microgrids are legal. 

The new rules establish classes of microgrids, define types of generation they can use, and clarify the role of utilities and municipalities. Jared Leader, SEPA senior associate for utility strategy, issued a brief Friday describing the three classes of microgrids that can be developed under the rules.

  • Personal microgrids, which will provide power to one or two consumers and can, with PREC permission, provide excess energy and grid services to neighboring customers
  • Cooperative microgrids, which will serve three or more cooperative members, under two subcategories, small co-op microgrids of less than 250 kW or large co-op microgrids of more than 250 kW. Like personal microgrids, co-op microgrids can sell excess energy and services to others.
  • Third-party microgrids, which have owners or operators who sell energy services to customers under rates approved by PREC and set on a project-by-project basis. Owners can earn a reasonable rate of return for the first three years of operation.

Humanitarian workers, non-profits and private companies have cited the need for regulatory clarity and planning to build out a robust network of permanent microgrids.

The rules define ‘renewable microgrids’ as those that can generate 75 percent of their energy from renewables — solar, wind, geothermal, hydropower or biomass – and 25 percent from fossil fuels. A combined heat and power (CHP) microgrid must produce at least half of its total energy from the useful thermal energy captured from the plant. A hybrid microgrid may incorporate CHP and renewable systems, but the non-CHP system must generate 75 percent of its energy from renewables.