What is this project?
-I am building a street-legal three-wheeled motorcycle, which runs off electric power. I aim to reach 1000 MPGe. For comparison, walking takes about 100 (kilo)calories per mile, which equates to 315 MPGe and bicycling takes about 38 (kilo)calories per mile (at 20 mph), which equates to 964 MPGe. I aim to top both of these numbers. A lofty goal, I realize.
Do you think you can actually make it that efficient?
-Based on my calculations, even if I can only bring the coefficient of drag down to .30, I should be able to achieve 1000+ MPGe at speeds below 22mph. If I can reach a coefficient of .20, that speed will change to 25mph, and 900+ MPGe up to 35mph. While these are only numbers on a spreadsheet, the give me hope that I may achieve my goal.
What is it based off of?
-It is built completely from the ground up, with no “donor car”. It does, however, use a motor from an electric golf cart, but to say it is based on the cart would be an exageration, as I have never even seen the cart it came off of.
Why did you decide to do this?
-After building a bicycle, I wanted to design something bigger, and after seeing Top Gear’s attempt at an electric car, it didn’t seem like it would be too difficult.
How much does it cost?
-The final price tag looks like it will be settling around $1400. While I had expected the number to be around $1000, I did not take into account consumables (welding wire and grinder blades ran about $100), and all the “insignificant parts”, which really start to add up.
How much power does it have?
-This is a difficult question to answer. My motor produces 3.2 hp continuously, and peaks around 16 hp, with an estimated 148 ft-lb of torque. While the horsepower figure seems tiny, remember that most cars are not using their rated horsepower during non-racing circumstances and that most cars weigh between 2800 and 3500 lbs. When you combine this with better aerodynamics, less rolling resistance, fewer power drains such as air conditioning, and a lower top speed, I believe my power will be more than ample.
How much will it weigh?
-My goal is 400 lbs. I am not quite sure where I am as of yet, but I believe I am well below that figure.
How fast will it go?
-My original goal was 40 mph, however based on new calculations, I may be able to exceed that.
How long will it go between charges?
-The normal power draw is 2.4 kW, while the peak power is 12 kW. My battery pack holds 5.52 kWh, which would suggest a little over 2 hours at normal power, but taking into account acceleration and the detrimental effects to the batteries of drawing more than 75% of their power, I think 1 hour to 90 minutes is a reasonable estimate. This should get me around 50 miles as a conservative estimate.
How long will it take to charge?
-The chargers I purchased were rather cheap, so they only put out 288 W total. If I go about 10 miles on an average day, this would take 3 to 4 hours to recharge. Were I to go my maximum distance, likely around 50 or 60 miles, they would likely take about 15 hours to fully recharge.
How much does it cost to charge the batteries?
-Assuming my chargers are somewhat efficient, a full charge (50-60 miles) should cost around 30 cents.
Will it be street legal?
-Barring any unforeseen difficulties, yes. It will be registered as a “Specially Constructed Motorcycle”, but will only require a Class C (Driver’s) License to operate.
Will it have any kind of body?
-I plan to build a fiberglass body, which, along with my plexiglass windows, should form a smooth aerodynamic shape, allowing me to reach my efficiency goals.
What special tools do you need to do this?
-As of yet, I have used a simple hand drill, a $100 welder, a $30 angle grinder, an electrician’s tool for cutting and stripping wire, and a set of clamps. Nothing too expensive or complex.
Where did you learn to do this?
-The internet is a great resource. I began here:
http://www.diyelectriccar.com/forums/showthread.php?t=669&redir_from=668
And whenever I have questions, I do a search on one of the following sites:
Buggiesgonewild.com (For low powered electric motors)
Forum.atomiczombie.com (For welding and design)
Ecomodder.com (For fuel efficiency)
Locostusa.com (For general car questions)
Diyelectriccar.com (For miscellaneous electric car topics)