RechargeIT was launched in 2007 as an effort within Google.org to demonstrate plug-in electric vehicle (EV) technology and accelerate its adoption. With several new EV’s now available in the marketplace, we’ve retired the RechargeIT initiative. In fact, we’ve updated our EV infrastructure to include more than 30 of the newest plug-in vehicles as part of our employee car sharing service, Gfleet. We’ve started with the Chevrolet Volt and Nissan Leaf and we’ll be adding new models as they become available. We’ve also been busy creating the largest corporate EV charging infrastructure in the country, with over 200 chargers currently in place, with the goal of electrifying 5% of our parking spaces at our Mountain View headquarters.

When we launched RechargeIT in 2007, there were no commercially available plug-in hybrid EV’s available in the market. So we developed a demonstration fleet at our headquarters in Mountain View and launched Gfleet to make the cars available to Googlers. We collected data from the fleet and made it publicly available, and also conducted a controlled Driving Experiment to assess the performance of plug-in vehicles. Our plug-ins achieved 93+ MPG, and you can still view historical data from our fleet.

The RechargeIT Demonstration Fleet

Back in 2007, with no commercially available vehicles to test, we had eight Toyota Prius’ retrofitted to make them plug-in hybrid vehicles. The vehicles used the Hymotion/A123 production plug-in hybrid kit. All of these cars were outfitted with data recording devices that tracked technical and environmental performance, use patterns and charging history. We used both electricity and gasoline consumption data to calculate the total energy use for each vehicle to get “real world” performance data. In order to compare this data to other cars under similar conditions, we equipped four existing conventional hybrids with the same data recording devices. With this data, we were able to measure more realistic MPG efficiency of plug-ins over conventional hybrid vehicles.

The system to collect data from our fleet consisted of an embedded computer running Linux, a wireless data card, a GPS and an AC power monitoring device to monitor charge power. The embedded computer was connected to the vehicle’s CANbus (a data bus present in all new vehicles), and collected relevant data such as speed, distance driven, fuel use, and the vehicle’s high voltage battery parameters. Information from the extended hybrid battery, such as voltage, current, charge state and battery temperature, was also accessed and archived for data analysis.

During charging, the system monitored and recorded the AC charge power. The fleet manager used GPS to track the vehicle’s location. In addition to the data collected on board, we used a fleet fueling card that accurately recorded the amount of fuel used by each car which was then uploaded to our servers and used for the miles-per-gallon calculation. Once all the data was uploaded to our servers, any necessary calculations were done (such as calculating CO2), and the data was graphed and made available publicly. Data was available at the fleet level, individual car level and charging event/trip level.

The driving experiment

We noticed that employees primarily used the plug-in fleet for short trips close to our headquarters, so the data wasn’t truly representative of typical U.S. driving patterns. While the data showed significant MPG improvements over our standard hybrid cars, we wondered what the data would look like if the vehicles were used for more typical trips. We were also curious to know how our plug-in vehicles would compare to other hybrid and non-hybrid vehicles that are typically found in the US fleet. Hence, the RechargeIT Driving Experiment was born.

Our Results: The RechargeIT Driving Experiment

Electricity usage for plug-in vehicles:
Ford Escape Plug-In 133.2 Wh/mi, Toyota Prius Plug-in 139.6 Wh/mi


In total, it took just over seven weeks to complete our driving test for all our vehicles. The PHEVs performed significantly better than the standard hybrids. And they greatly outperformed the average American fleet fuel economy of 19.8 MPG, with the Priuses getting as much as 93 MPG across all trips and 115 MPG for city trips, while the Ford Escape SUV Plug-in Hybrid conversion got 49 MPG! See the full results to explore detailed data from the experiment.

See full results »