LomboXnet: electric cars as storage devices in a solar powered smart grid

LomboXnet, the small-scale ETTH network in the Lombok part of Utrecht, is making an interesting turn. As it awaits a viable IPTV solution, it has decided not to expand the network, for now at least. Instead, it is developing a smart grid, based on the ETTH network, several solar plants and ... storage!

Solar panels are mounted on rooftops of local schools etc. and the smart grid will help to match supply and demand as much as possible. Weather forecasts will be included in the input. This is where storage comes in, and the company has decided to allow electric cars to act as storage devices for the grid and the local community. Charging and home use will alternate, depending on weather conditions.

A few numbers from the solar industry (approximations):

• Existing electric cars (Nissan Leaf) have storage of c. 24 kWh, enough to run a household on for c. 3 days and LomboXnet for c. 8 hours.
• New electric cars (Tesla S) can fully charge at c. 20 kW, which translates in just half an hour. Storage is 85 kWh. Any full day's drive in the Netherlands normally doesn't use more than half of this, leaving the rest for home use. Such cars are currently cheaper than buying comparable storage capacity on a stand-alone basis.

Local (de-centralised) energy production and storage may mean the end of large energy distribution & network companies, although for now they will be needed to make it through the night and through the winter. Solar energy is becoming ever more viable by the day, as a result of increasing efficiency of both production (solar cells are becoming better, faster and cheaper) and storage (driven by the smartphone/tablet/laptop industry).