Brenthasty
Posts: 51
Joined: Tue Dec 23, 2014 6:24 pm
Delivery Date: 13 Nov 2014
Leaf Number: 023724
Location: Near portland oregon
Contact: Website

Re: Leaf roof solar panels?

Wed Jun 08, 2016 12:24 pm

This would work good to power the 12 vdc system/sterio/climate control loads, alliviating the traction packs need to power those loads through the dc/dc converter.

The roof can harvest near 300 watts or .3 kwh per hour with modern 23% efficient monocrystaline semi flexiable panels available for a mere 2$ per watt from ebay.

Several 30 watt panels each with thier own micro mppt. They can be adhered with a removable quality 3m automotive double stick tape. The power lines could be descretely run along the rain gutter roof line and fed into the 12vdc bus under the hood or under the hatch.

Then replace the lead acid 12 volt battery under the hood with a high capacity lithium battery; maby made from several leaf battery cells. Set the mppt's to fill the lithium battery to up to 15 vdc then the traction pack dc/dc will remain off until the pack drops below 12 vdc.

LeftieBiker
Posts: 6941
Joined: Wed May 22, 2013 3:17 am
Delivery Date: 31 May 2013
Location: Upstate New York, US

Re: Leaf roof solar panels?

Wed Jun 08, 2016 12:33 pm

Set the mppt's to fill the lithium battery to up to 15 vdc then the traction pack dc/dc will remain off until the pack drops below 12 vdc.


If we could change the charging algorithm then the first order of business would be to correct it for the current FLA 12 volt battery.
2013 "Brilliant Silver" SV with Premium Package and no QC, and 2009 Vectrix VX-1 with 18 Leaf cells.

The most offensive, tasteless phrase in use here is "Pulled the trigger." I no longer respond to posts that use it.

Durandal
Posts: 308
Joined: Wed Sep 21, 2016 8:55 am
Delivery Date: 22 Sep 2016
Leaf Number: 025018
Location: Central Arkansas

Re: Leaf roof solar panels?

Tue Sep 27, 2016 12:00 pm

In using my Leaf, usually my 12v usage is 200-300 watts. Unless you're doing a lot of very slow driving, you're unlikely to get over 1.25 hours of driving around, using that 300 watts. 1.25*300=375Wh. So, that's about 1.6 miles of range if you're getting 4.4 miles/KWh or so.. Given that, 50w of solar on the roof would keep your 12v topped up while parked, and reduce the usage of the DC to DC converter when driving. Another consideration on the matter is how much drag the panels would produce, even if the panel is a flexi panel, adhered to the roof, the connection points likely will be raised up and probably cause enough drag to negate the benefit of the panel.

Solar panel solar shield for the front of the car while parked? haha.
Pulled the trigger on going EV on 10/2016 with a 2012 Leaf, and a Tesla Model 3 reservation expected to receive in June 2018.

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