Boulder turns to the sun for public EV charging

Solar power and electric vehicles are an obvious pairing for carbon-free transportation. The city of Boulder, Colorado has deployed two public charging stations powered entirely by the sun.

Colorado is one of America’s more energy-progressive states and notably is home to the National Renewable Energy Laboratory and the Rocky Mountain Institute. The city of Boulder recently installed two new public charging stations that will allow EV owners to charge up on sunlight for free.

“It’s totally sustainable and a complete use of our natural resources,” said Glenn Magee, Construction Manager for the city of Boulder, of the EV ARC system.

The Envision Solar EV ARC is a solar powered Level II charging station for plug-in electric vehicles. It is a standalone system that collects electricity from a tracking solar panel canopy array and stores it in a 22 kWh battery, which then supplies power to the vehicle as needed. Envision says the solar panels can generate 16 kWh per day, enough to charge a Nissan LEAF to 75% capacity.

One of the main benefits of the EV ARC, aside from its negligible operating costs and carbon-free electricity supply, is that it also incurs virtually no installation costs. The need for a foundation, trenching, building permit, and grid connection result in steep installation costs for conventional charging stations; the Envision EV ARC system does not require any of the aforementioned installation work and fits in any standard parking space, bringing EV charging to locations that otherwise would be unable to accommodate the infrastructure.

Though costs remain high and Level II charge rates remain slow, the Envision Solar EV ARC system represents a first step toward truly carbon-free electric vehicles. Harnessing the power of the sun to charge EV batteries is the ultimate solution for clean personal transportation.

However, many feel that the future of public charging lies with DC fast charging, which could eventually render most Level II public charging irrelevant; it will be difficult for solar charging stations coupled with energy storage to provide the necessary power output for fast charging where vehicles will charge more frequently.

In addition, solar panels remain relatively costly and inefficient, and the costs associated with large batteries make solar-plus-storage EV charging stations too expensive for widespread deployment with current technology. Each EV ARC station costs approximately $40,000, though with large orders the price drops dramatically.

As battery and solar technology improve and costs are lowered, however, this is a very intriguing avenue for charging infrastructure. The city of Boulder has set an example for others to follow at the forefront of clean transportation.