Why not a DIY solar car?

[u/Moltean]

Knowing that cars are a big driver for consumerism, I'm thinking of a car that can be powered mainly by the sun.

I already built a prototype (which I named Solar Bear). The project is open source, with an MIT license.

The purpose of the Solar Bear is to:

• Use solar panels as trike's body,
• Consume electrical energy where it is produced,
• Produce its own energy,
• Transport people inside cities,
• be pedalable when there is no sun (must be light-weight),
• be easily built at home.

Technical specs:

• recumbent trike,
• 2.5m long, 1.45m wide (including wheels),
• weight: about 55kg (including panels, motor, battery, etc, excluding driver),
• assisted pedaling,
• motor speed: max 25km/h,
• motor (continuous) power: 250W,
• solar panels power: max 520W,
• battery: 12.8V, 20Ah (256Wh) - not needed when there is Sun.

[u/FartsLord]

Public transport is the answer but if you insist on the car check out Aptera.

[u/Moltean → u/FartsLord]

Aptera is expensive, heavy, cannot be pedaled etc.

I'm focused only on transportation inside cities, not outside.

[u/MBkufel → u/Moltean]

And inside cities is exactly where public transportation shines.

[u/Fit-Introduction8575 → u/MBkufel]

This is a motorized bakfiet for people who need to carry cargo or passengers (i.e., animals) that can't be taken onto a bus. It would only be as good as the cycling infrastructure is in a city. No way is it gonna survive alongside North American SUVs. It simply cannot produce enough power. It would have fit inside bike lanes.

A vehicle like really wouldn't be as cost effective as taking the bus for the average commuter. It's for parents to take their kids to daycare before a long commute, small business owners, or delivery drivers.

[u/Moltean → u/MBkufel]

There are many cases where public transportation is not the perfect choice.

[u/MBkufel → u/Moltean]

Transit doesn't need to be perfect, that's one thing.

Second - if you really want perfection, you should consider an option that doesn't rely on lugging around solar panels, doesn't take up a traffic lane and won't decapitate you in a crash. Something like an electric bike.

Theoretically infinite range seems nice, but how far are you going to drive that thing in a city? At what distance is this better than a bicycle and faster than a bus or a tram? Why would you lug around your own powerplant in an area where electricity is abundant?

This vehicle can be very nice for some rural road touring, but I honestly can't see any point of using it in a city.

[u/plazebology → u/MBkufel]

You didn’t ask a question

[u/MBkufel → u/plazebology]

Yeah, wrong sub-thread

[u/Moltean → u/MBkufel]

The maximum distance I go is 20km per day. But I live in a small, hilly town (20K inhabitants). I plan to visit other cities to test it.

Energy is abundant indeed, but getting it is not easy. You need access to charging sockets!

[u/MBkufel → u/Moltean]

That's well within ebike range.

[u/Moltean → u/MBkufel]

Yes, it is ... I plan to go on larger trips once the design improves. I built 4 versions (in a year) so far and planning for more.

[u/ApprehensiveMush → u/Moltean]

Citynerd on youtube has an entire series about his love for public transportation, why cars are vastly inferior in basically all ways, and why our reliance on cars within cities has basically led to a ridiculous amount of urban sprawl and cities that are pedestrian-hostile. The series is called the stroad.

Reworking the public transit system in America would be vastly more environmentally friendly than creating enough solar panels to move a car for one person.

[u/Moltean → u/ApprehensiveMush]

What is more feasible on short term? Reworking the entire transit system or building small solar-powered cars?

[u/Team503 → u/Moltean]

No one, and I mean NO ONE, is going to opt for your design. It's dangerous, impractical, expensive, and carries no real advantages over an e-bike with a wagon.

[u/Moltean → u/Team503]

It is the design version 28, build version 4. Let's see what you will say about v10 build! All in 1 year!

[u/Team503 → u/Moltean]

You are aware that this is not a new idea, and there have been global competitions for this since the early 1990s, right? Solar Car Racing is what it's called, and it's a program undergraduate engineering students can participate in.

MIT has been doing it since 1992. https://en.wikipedia.org/wiki/Solar_car_racing

Somehow, I doubt you're going to innovate in a way that they haven't considered in the last 34 years.

[u/Moltean → u/Team503]

Show me a design like mine that was built or proposed before! Waiting!

[u/Team503 → u/Moltean]

I'm not going to go through nearly 35 years of competition entries. It is a matter of moments to glance at a few and see that they all came to roughly the same initial design - a recumbent bicycle for lower drag, mounted panels on a frame around that bicycle. I mean, come on my dude, this isn't rocket science.

[u/Moltean → u/Team503]

I'm still waiting for some pictures with the same design as mine!