The Solectria Sunrise

The Sunrise EV2 Project Homepage

Welcome! We are a group of dedicated electric vehicle enthusiasts whose goal is to create an affordable, high performance electric kit car that anyone of modest skill can assemble. The Sunrise EV2 is a four-passenger pure electric sports sedan, designed to meet all the safety, performance, and comfort requirements of a modern state-of-the-art automobile.

The original Sunrise was designed by Solectria Corp. using the Hypercar principles of Amory Lovins. It achieved remarkable efficiency and range, through the use of lightweight construction, innovative design, and superb aerodynamics. Unfortunately, only a handful were produced.

The Sunrise EV2 project began with the purchase of the last unfinished Sunrise from Solectria CEO James Worden. It is being redesigned as a kit car, along the lines followed by manufacturers of light plane kits for the EAA (Experimental Aircraft Association). The steps are:

  1. Build a working prototype, that interested parties can see and drive. Test the design and verify performance.
  2. Publish plans, sufficient to build the entire car from scratch, just as we are doing now.
  3. Provide key components produced from our molds and tooling, such as the fiberglass body and welded chassis parts, to simplify construction.
  4. Produce parts kits and subassemblies. For example, all the major parts needed to build the wiring harness, body hardware, rear subframe, etc.
  5. Offer a complete car kit. Combined with generic parts purchased new and those from a donor vehicle, anyone who can handle a screwdriver and wrench could put it together.
  6. Someday, perhaps a fully assembled production automobile. I doubt we will get to this point for years, due to the costly regulatory requirements.

Our goal is to make the Sunrise EV2 as modular and open source as possible; like a PC clone, where many different parts can be used, from many different vendors. We'll provide the basic "box". Builders can then use any motor, controller, batteries, charger, interior, and instrumentation they like. Depending on your budget and performance requirements, your Sunrise can be AC or DC, lead-acid or lithium batteries, etc.

We look forward to having a community of Sunrise EV2 builders, where members can exchange ideas, buy/sell/trade parts, and assist others in building their cars. Check this website out occasionally to see how we're doing.


June, 2014: Like the Beatles said, "Here comes the sun... It's been a long, cold lonely winter." We had snow until the end of April! The garage was so cold that I couldn't do much body work. The tooling gelcoat wouldn't set, and even the "fast" West System epoxy hardener took forever to cure.

But Spring finally came to Minnesota. I was able to make molds from the donor car's rear wheel wells, and make parts from these molds. These are still rough, and need some finishing work. But the insides are smooth, and they precisely reproduce the mounting locations for the rear suspension subframe, springs, and shock absorbers.

Next, on to the front wheel wells. It will be the same process: Smooth the inside of the donor car's wheel wells, and make fiberglass molds from them. The molds will be used to make fender wells for the prototype, and become part of the production chassis mold.

Other recent updates:

Lee's EVs

In this section, I'll be regularly posting EV tips and techniques to save you money, find parts, measure performance, and improve your EV. As new ones appear, the old ones will move to the Lee's EVs page. Purchases contribute to the Sunrise EV2 Project. If you like what you see and want me to write more of them, please click the "donate" button below. :-)

EV Motor Controllers

EV motor controllers have been around for a very long time! If you're interested in how they work, or even thinking about building your own, it's important to understand a little history.

Since just about every controller today uses transistors, I thought I'd document the earliest transistorized controller I know of. It dates all the way back to 1968; before microcomputers, before integrated circuits, and even before silicon power transistors!

The schematic at right is a PWM series motor controller from 1968 (from Motorola Application Note AN-189). It was designed for a golf cart with a 36v pack, and delivered up to 200 amps. A single transistor big enough to handle that much current didn't exist; so they used eight smaller mass-produced transistors intended for car radios in parallel (a trick that is still being used today).

Germanium power transistors have a very low on-state voltage drop; 0.2v at 50 amps for the ones in this controller. That's very good, and hard to match even today! But germanium transistors are also easily damaged by high temperatures and high voltages. They also switch rather slowly (compared to modern transistors). This limits the switching frequency to a few KHz. Such controllers tend to "whistle while they work". :-)

The controller works reasonably well, and could be built with modern parts. You would need to substitute silicon transistors for the nearly-unobtainable germanium transistors. The small ones are easy; for example, a 2N4401 for Q1, Q2, Q5, and Q6, and a TIP42 for Q3 and Q7. Unijunction transistor Q4 would be a bit harder to find -- the 2N6027 is a close modern equivalent. Q9-Q17 are the hard part. Modern silicon PNP transistors like the 2N5884 would work, but they have a much higher on-state voltage drop. You would need to reduce the value of R24, and use more transistors in parallel to spread out the heat.

A more practical approach is to "complement" the circuit -- Reverse the supply polarity, reverse all the diodes, and replace all PNPs with NPNs and vice versa. This makes the high-power output transistors NPN instead of PNP, which are much easier to get. In fact, a single large NPN darlington transistor module can replace Q8-Q17, which also eliminates R24 and the emitter balancing resistors R34-R42.

For more examples of EV motor controllers, click here to go to the Motor Controllers page.

Electric Vehicles in the News

Donations for the Sunrise EV2 Project

Interested? Want to get involved? There are several ways you can help.

Contact us: Questions or comments? Corrections or problems with this web site? Contact Lee A. Hart by phone at (320) 656-9574, by email, or by mail at 814 8th Ave N, Sartell MN 56377-2240.

Design: Producing the best possible EV requires the best possible minds. The Sunrise EV2 development team has over 100 years of combined EV experience, but we are still learning and improving as we go. If you have ideas for improvements, can help with vehicle design, construction, or testing; or have skills you think we can use, please contact us!

Labor: The Sunrise EV2 prototype is being assembled at our shop in Sartell MN. At present, we are building our prototype composite body and the molds to produce it. It's very labor intensive, so if you're in the area and have some time, please contact us about a visit. See and help build the prototype, and in the process learn how to build your own Sunrise EV2.

Components: Most of the parts and materials to build the Sunrise are being donated by our development team or interested individuals. Our motor, controller, and innumerable tools and shop time have been provided, but there is alway more. Do you have any EV related parts that could be of use? Contact us and see!

Donations: Developing a car is an expensive project. The project is entirely funded by our development team and donations from interested individuals and businesses. Donations will be credited toward future purchases of Sunrise EV2 products. Contributors are also given special attention by members of the EV2 team! Send donations to the Sunrise EV2 Project c/o Lee A. Hart at the above address. To contribute using Mastercard Visa or Paypal, use the "Donate" button below. Every penny helps!

Steven Taylor's Solectria Sunrise

The Sunrise EV2 Project, copyright 2007-2014 by Lee A. Hart. Website created 2/4/2008 by admin. Last update 7/11/2014 by Lee A. Hart
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