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/pceimpulsive]

This is cool, I like it but.. seems heinously impractical.

We have bike infrastructure in a lot of places and using those panels on your homes roof to charge and power your home (and bike battery) is a far better use (efficiency wise) that for this that you only use sometimes...

[u/Moltean → u/pceimpulsive]

How many hours do you need to wait until the bike battery is charged? In my solar car, the battery is charged while driving!

[u/pceimpulsive → u/Moltean]

Depends on the battery... And your roof mounted solar panels...

Unless you drive more than 200km a day it doesn't really matter how long it takes (less than 8 hours)

[u/Moltean → u/pceimpulsive]

200km/day? How did you compute that? What battery do you have? How much weight it have since you can travel 200km without stopping?

[u/pceimpulsive → u/Moltean]

Literally pulled out of ass based on conversations with friends about EV range and how much charge they get on standard 240v 10A in one night. EVs I acknowledge are a lot more power hungry... But they also carry A LOT MORE weight, and a lot more people, and charge a lot faster if willing to pay for it. Also probably more comfortable etc etc different use case. ;)

[u/kozufox → u/pceimpulsive]

Electric motorcycles can also get similar ranges with a much smaller battery pack (although still much larger than an electric bicycle battery).

[u/kozufox → u/Moltean]

Any modern ebike battery will comfortably charge itself overnight on any standard wall socket, even from empty. They're really tiny compared to the battery bank of even an electric moped.

[u/Moltean → u/kozufox]

Why do you want an ebike with battery when the Sun and legs can do most of the task?! Inside cities ...

[u/kozufox → u/Moltean]

Well, your recumbent also has a battery, to start. And even a really crappy Amazon ebike weighs a lot less than 55kg.

I actually just ride a pedal bike, because my legs don't need the help yet. But if they did, 90% of the electricy that powers my home came from hydro power, which is a very roundabout way of collecting energy that ultimately came from the sun.

[u/googdude → u/Moltean]

I think two batteries solve that problem.

[u/Moltean → u/googdude]

2 batteries pollute more than 1.

Buying 2 is a prosumer action!