Clean-technology start-up Beam Global believes it has advanced the case for off-grid solar energy as an aircraft power source with what it says was a record-breaking flight across central California. Last week, Joseph Oldham, CEO of New Vision Aviation, a not-for-profit organization providing flight training for disadvantaged communities, flew a Pipistrel Alpha Electro 260 miles from Fresno to Lodi, with stops in Madera, Merced, and Modesto. The all-electric light aircraft was powered entirely with Beam Global’s Electric Vehicle Autonomous Renewable Charger (EV ARC) system.
According to San Diego-based Beam, the technology generates electricity from solar power, which is delivered directly to vehicles. The EV ARC recharging units take up the space of a standard car and are intended to be quickly deployed to airfields or wherever they are needed by electric aircraft operators.
At the top of each unit is a solar array that converts sunlight into DC electricity, which is then stored in lithium-ion-phosphate batteries, from which the charging unit is supplied. The EV ARC unit includes a power management system that releases an electric charge only after the aircraft (or ground vehicle) has digitally confirmed that it is the intended recipient.
“The solar array moves during the course of the day, following the sun, and this gives us about 25 percent more electricity than a fixed array on a rooftop,” Beam CEO Desmond Wheatley told FutureFlight. “It [the EV ARC] can determine where the electricity comes from. During daylight, it charges directly from solar power, and at night [or in overcast conditions] it releases all the stored power from the batteries to the charger.”
The system converts AC power to the DC power that the vehicles need. “We’re pushing for new technology to have a full DC circuit that would generate, store, and deliver DC power, giving a 15 percent improvement in efficiency,” Wheatley explained.
Purpose-built electric aircraft like the Alpha Electro have power management systems that calculate the available power in the batteries to show the pilot the real-time endurance limits, taking account of required safety margins. Just as an electric car burns through more of its charge while climbing a hill and then saves charge while going down the hill, an electric aircraft consumes less power once it is at cruise altitude.
Beam already has its EV ARC deployed for multiple ground vehicle operations in around 100 U.S. cities, including New York City police cars. Wheatley said that installing it where the equipment is needed does not require any construction work or laying of power cables since it operates completely off-grid.
For some higher-density aircraft applications, such as eVTOL air taxi services, current recharging times might seem slow. Beam estimates it takes a couple of hours to fully recharge an aircraft like the Alpha Electro, pointing out that it can be partially recharged in less than half an hour.
According to its Slovenia-based manufacturer, the two-seat training aircraft has a flight endurance limit of one hour, with a 30-minute reserve. The longest sector on Beam’s record-setting trip was around 50 miles.
Wheatley acknowledged that for electric aviation to be viable for more applications, faster charging times will be required. “We’re getting more energy density in batteries the whole time, and we’re also getting better at charging them at appropriate speeds,” he said.
Beam envisages a variety of business models for its EV ARC units in the aviation sector. For instance, it might sell the equipment directly to companies looking to provide charging services, with maintenance support provided. In other cases, the units might be installed at an airfield with the financial support of a sponsor.