NREL’s Campus EV Charging Stations are Now More Integrated with the Grid
July 25, 2016
The National Renewable Energy Laboratory's (NREL's) campus electric vehicle (EV) charging stations, which encourage employees to participate in workplace charging by powering up their plug-in electric vehicles (PEVs) in exchange for research data, are now enhanced with integrative software that links drivers' expectations with extensive renewables in the laboratory's campus grid.
To achieve this, transportation researchers with NREL's Electric Vehicle Grid Integration group developed a hardware and software feature that allows drivers to play a role in an integral component of campus energy management strategies, intelligently aligning vehicle charging with off-peak demand hours and NREL's photovoltaic (PV) generation. The program uses real-time campus data and a web application to import basic information about drivers' cars while charging, such as which station a driver plugs in to, the anticipated departure time, and the number of charged miles needed before departure. The application then estimates the amount of energy a vehicle's battery needs throughout the day, adjusting the output level of charging power accordingly. Researchers have completed testing of the application and charging management software on one of the charging stations, and the new system will be extended to all employee stations soon.
"With better control of the EV charging stations, we can more fully utilize campus PV generation," said NREL Engineer Myungsoo Jun, explaining how the system is programmed to increase charging power when PV generation is high or when net campus loads are low, or vice versa. "This provides financial benefits for NREL by reducing peak loads and avoiding expensive peak demand charges. It also reduces PEV charging-related emissions by linking transportation energy demands with NREL's PV generation."
Researchers worked closely with NREL's Sustainability, Infrastructure Transportation, and Engineering Operations Office in order to install and deploy the updated equipment and communicate the upgrades to staff. The campus charging stations were rebuilt by NREL staff to enable this new exchange of data. As PEV drivers at NREL take advantage of the new technology, researchers are concurrently collecting data on charging station user behavior, campus energy use patterns, cost savings, and the technology's ability to most effectively use NREL's electricity grid to charge vehicles.
"Ultimately, the goal is to enable greater electrification of transportation. That requires charging infrastructure, and our managed EV charging project demonstrates leadership by integrating renewable energy," said Jun. "Our expectation is that others will follow our lead."
NREL's leadership highlights how EV charging can be achieved at a low cost and can transition transportation energy from fossil fuels to clean renewable energy. The laboratory's approach to integrate driver needs with campus-level forecasts and load data, to activate and deactivate individual charging stations within a campus, represents a first-of-its kind demonstration.