The Israeli Hebrew language web site “TheCom” covering the Israeli Telecom industry has a recent article on charge point telecomunication infrastructure. I have translated the article to English below.
“Electric car charging positions are becoming common all over the world. Beyond the issues of power, charging stations, wide network deployment raises complex issues in the fields of communication and control for the cellular wireless technologies.
Better Place has completed as of this week 800 points, establishing the infrastructure to load electric cars in Israel. More on the Israeli aspect of the charging electric field in the article below. This area is already in full swing , and the hope is the that the solution may solve our oil energy supply crisis .
One successful new company in the world in this regard is the American comany Coulomb Technologies, which offers electric vehicle charge positions under the brand name ChargePoint. Cooulomb Technologies also established a network called ChargePoint Network, which has a very interesting communication solution The company has already installed charge points in U.S. major cities such as Chicago, San Francisco, and San Jose and is now is spreading around the world.
Communication between the positions in the area (parking lot, neighborhood follows wireless communication standard 802.15.4-2006 This short range technique (up to 10 meters ), based on WiMesh, uses relatively low throughput speeds (up to 250 Kbps) at a frequency of 2.4 Mhz. This unlicensed frequency technology is also known as ZigBee. The network of one mesh is capable of connecting approximately 100 charging stations in . The advantages of this wireless technology are relatively low consumption of bandwidth and immunity from interference.
Communications between the network and the parking lot is done via Cellular Data either GSM cellular networks or CDMA. Throughput requirements are low enough for GPRS network connections.
The network is connected to municipal and private parking metering systems, so that the client communications device can also get charging authorization for municipal or private parking . The transaction communication is protected using encryption of 128bit AES. The final customer has access to the network through his account on the web portal. The portal is connected to Google Maps (to detect charging stations along the route of the electric vehicle, and can be accessed via browser using HTTPS. The client, after signing an agreement with the charging grid provider , receives a “smart card” chip communicating with RFID, To start the transaction the client places the smart card near the charging point.
An alternate transaction method is the use of the client’s cell phone, by sending SMS or by communication between the mobile phone application and the chage point quite similar to paying for parking using a cell phone. The charging current is 15 ampere on at 110 or 220 volt. Charging may take several hours, depending on the type of car and the battery charge status .
Better Place reported, as mentioned above, to have installed 800 charging positions to date. It plans to install an additional 500 positions in the next quarter of 2009. By the end of 2010 there will be half a million positions in the country and more than 100 battery swap stations. Through the end of 2020 there are planse to reach 2.8 million charging points and 200 battery swap stations.
According to Better Place, charging will take two hours at most, because they use 32 amper charging circuits. The price of the final electricity cost to the customer according to the Better Place isapproximately 700 NIS per year, not including the surcharges for infrastructure, collection, maintenance and battery swaps. In any case, it would be cheaper than gasoline or diesel fuel.