Cleantech Market Intelligence
EV Charging, Simplified
One of the most vexing challenges surrounding EV ownership is how apartment and condominium dwellers will pay for the power they use to charge their cars. Starting later this year, EVs will be able to send billing information over a power line or via wireless communications to avoid this problem.
As I wrote at the end of 2011, the HomePlug Green PHY standard enables data, such as a vehicle identification number, to be sent over a power line. The low-power communications channel can send messages about the vehicle, account information, and the amount of power consumed to smart meters or other home energy equipment.
Multi-unit dwellings are particularly challenging environments for EVs because several customers can share a single parking spot. Moreover, the meters to account for the power consumption are often far from the charging spot and out of range for wireless communications. Sending billing data over the power line also avoids the problem of having to set up additional meters or manage submetering.
New Models Coming
Qualcomm Atheros was the first to market with a Green PHY chip, and startup Greenvity Community is the first with a hybrid chip that can process both power line and ZigBee communications. At the Consumer Electronics Show earlier this month, Hung Nguyen, president and CEO of Greenvity Communications, told me that multiple automakers offering EVs will launch models later this year with the company’s chips embedded. Greenvity is also working with EV charging equipment companies to similarly embed the chips in their products.
Greenvity is partnering with Mitsumi Electric to create modules with the integrated Green PHY and ZigBee chips that can be incorporated into home gateways or home area networks. Nguyen said that initially smart meter companies that are using ZigBee for communications can purchase a standalone box to bridge communications between power lines and ZigBee. The data would be sent from the point of charging, which could contain EV charging equipment or a simple 110-volt outlet, over the power line and then converted to ZigBee wireless data close to the meter. Nguyen expects smart meter companies to embed the hybrid chips in the future.
Also in the future, the power line could be used during overnight charging to send content to a vehicle, such as maps, directions, updates of applications, or even music or videos. Utilities could send price or demand signals to smart meters, which would pass them along to EVs to instantly react to changing conditions on the grid. Solving the billing challenge for multi-dwelling units will encourage property owners to support rather than avoid EV charging, as it can create another revenue stream while reducing the technical requirements and cost.