ChargeCar Community Conversions: Practical,Electric Commuter Vehicles Now!H. Ben Brown, Illah Nourbakhsh, Chris Bartley, Jennifer Cross, Paul Dille, Josh Schapiro, Alex StylerRobotics InstituteCarnegie Mellon UniversityPittsburgh, Pennsylvania 15213Abstract—The technology for practical, short-range electriccommuter vehicles (EVs) is here now! The ChargeCar projectat Carnegie Mellon University aims to exploit today’s technologyto make efficient, clean, quiet, commuter electric vehicles avail-able to the public, while providing a basis for local economicdevelopment and increasing public awareness of EVs. We havedeveloped a “kit” of modular components that can be used toconvert a conventional gasoline-powered car to 100% electricpower in a matter of a few days, utilizing commercial-off-the-shelf(COTS) components, along with existing manufacturing facilitiesand automotive garages. This kit has been installed and testedin two Honda Civics, and has performed well in over 3500 milesof driving. The prototype vehicles have a range of 40+ miles,top speed in excess of 70 mph, and charge overnight on any120 VAC receptacle. Present efforts are toward commercializingthe manufacturing and conversion process, while continuingrelated research in compound energy sytems—e.g. battery plusultracapacitor—and pursuing educational efforts with the publicand local schools.I. INTRODUCTIONThe Community Robotics, Education and Technology Em-powerment (CREATE) Lab at Carnegie Mellon Universityseeks to co-design new technology innovations together withoutreach and engagement strategies that demonstrate andmeasure how diverse communities can use creative technol-ogy responsibly to catalyze positive social change. Ongoingprojects include GigaPan Education [1], which uses a low-cost gigapixel imaging robot for cross-cultural learning indozens of countries thanks to partnerships with UNESCO andNational Geographic; and Robot Diaries [2], which deploys atraining program together with programmable robot hardware,software and craft materials to bridge the technology fluencygender divide in middle school. The ChargeCar project [3]combines technology development for low-cost electric ve-hicle conversions with direct community engagement at thehigh school, college, professional and lifelong-learning levels.Technically, we optimize for conversion cost and labor hoursusing a systems-engineering approach, aiming to significantlylower the barrier to entry for independent, local garages toprovide electric vehicle conversions. We are also developingenergy optimization algorithms for compound power suppliesto demonstrate that low-cost batteries, together with high-power-density ultracapacitors or batteries, may yield a cost-effective solution to electric vehicle energy demands whencombined with intelligent, predictive, energetics controls.II. ELECTRIC VEHICLE HISTORYIn the early 1900’s, battery electric and gasoline-poweredvehicles were both part of the early personal transportationecology, although soon thereafter gasoline-powered cars be-came dominant due to the far greater energy density of gaso-line. While backyard conversions have been part of a popularsubculture for decades, these conversions typically take manymonths to complete, usually with lead-acid batteries, yieldingvery heavy vehicles with short range. The second-generationGM EV1 and Toyota Rav4-EV, produced in the late 1990’sand early 2000’s, demonstrated disruptive improvements inrange and reliability thanks to NiMH batteries and brushlessmotor technology. However legislative battles in the State ofCalifornia effectively killed the EV movement at that time byremoving state-mandated EV manufacturing pressure. Today,we can see a significant rebirth of interest and automotiveemphasis on electric vehicles, from the Nissan Leaf andMitsubishi MiEV to the Chevrolet Volt. These recent effortsconcentrate on using the best available batteries to achieve thegreatest possible range, in order to compete as successfullyas possible head-to-head against extant gasoline-powered cars.Ongoing research efforts are dedicated to increasing the powerdensity—including fast charging—and energy density of thin-electrode lithium and other exotic battery systems [4].While the proliferation of new EV models is promising,total sales of EVs in the US in 2011 amounted to less than20,000 vehicles [5], less than 0.15% of the total of 12.7 millionin vehicle sales [6]. EVs are marketed only in selected areas,and many potential buyers are unable to purchase new EVs.Further, the pro-oil politics of a decade ago is resurfacing withCongressman Mike Kelly’s bill to end the $7500 federal taxincentive for new EVs [7]. Thus, EV conversions may still playan important role in electrifying our nation’s transportationsystem, exploiting the distributed manufacturing capabilitiesand availability of used gasoline-powered vehicles. This maybe our only autombile option in the event of a major oilshortage.III. WHY ELECTRIC?While EVs are becoming more common-place, and tech-nologies have improved significantly over the past decades,EVs are still largely perceived as an oddity in this country, notready for public release. The general view is that EVs have in-adequate power and range, and will not be practical until theyPerception TruthMust be exact replacement for to-day’s cars.Perfect short-range commuter vehi-cle with today’s technology.Range too short—EV won’t serveall transportation needs.Typical daily commute under 40miles (US DoT). Many EV s haverange over 100 miles. Not intendedto replace all needs.Poor performance, inadequatepower.Good acceleration, highway speeds(e.g. Tesla Roadster).Battery technology not ready. NiMH batteries used reliably for 10years. LiFePO4 batteries have evenbetter energy and life.EVs will overload the electric grid. EVs ideal for off-peak chargingand load-leveling on a Smart Grid.Massive charging infrastructureneeded.Short-range EVs can charge on ex-isting 120 VAC outlets.TABLE IPREVALENT MYTHS REGARDING ELECTRIC VEHICLESICE Vehicle Electric VehicleMassive engine block tocontain hundreds of fuelexplosions/second.Electric motor with several movingparts.Hundreds of precision movingparts.A battery pack.Exhaust system to muffle the ex-plostions, cooling systems for en-gine and transmission, lubrica-tion system with periodic oil/filterchanges, fuel system, emission-control system system to mitigatepollutants, ignition system, belts,chains, hoses,