Florida Regulator Approves Tampa Electric’s Four-Year Microgrid Pilot

The Florida Public Service Commission on June 15 approved Tampa Electric Company’s four-year microgrid pilot program, which involves the installation of new direct current electric microgrid technology and generating equipment, called Block Energy System. The new system would have the ability to operate independently and also connect to the utility grid as backup. The purpose of the project is to test the ability of the technology to provide residential customers with high levels of renewable energy, as well as better reliability and resiliency.

The microgrid technology and related generating equipment would supply power to about 40 homes in Hillsborough County. The pilot program is expected to increase customer electricity consumption to 60 percent renewable energy and relieve the load on the distribution system at peak times. The homes will be interconnected with a community-based 240-kilowatt-hour battery storage and a pair of reciprocating natural gas generators totaling 350 kilowatts. The system will also function along with traditional electric generation equipment using an underground direct current distribution system. Each house will have an inverter installed to convert the power to AC, along with an average of 7.8 kilowatts of solar photovoltaic panels and 17.7 kilowatt-hours of standard battery storage. The housing development will also be connected to the company’s AC distribution system to provide power in the event of any failure of the microgrid.

The commission directed Tampa Electric to provide annual reports to the commission on the pilot’s performance, a survey in the pilot’s third year regarding participants’ willingness to pay a monthly surcharge for increased reliability, and a final report on the merits to make the program permanent. These reports will use data to compare the cost of providing local distribution service from a DC microgrid to the cost of a standard Alternate Current (AC) system.

The company asserts that if the DC Pilot meets its intended objectives, then the quantifiable benefits would include: increased renewable penetration, reduced system losses, reduced generation capacity costs, reduced system transmission and distribution capacity costs, reduced energy costs, and increased reliability. The initial capital costs for the program will be capped at $1.99 million and pilot participants will pay the same rates as other customers.

The company’s previous initiatives include a 632 MW AC system combined with 23 MWAC from three smaller projects built prior to 2018. Tampa Electric now has 655 MWAC of solar capacity, obtaining about seven percent of its energy from solar, according to its 10-year site plan to enhance electric generating capability to meet projected incremental resource needs from 2021-2030. By 2023, the company expects to have more than 1,255 MWAC of solar power representing about 12 percent of its energy, and enough to power more than 200,000 homes. Solar power has been increasing in Florida, although the state does not have a renewable energy standard.