The Lowdown on Solar and Lithium Batteries

Fred Mc · July 28, 2020, 07:18:54 PM

There has been a lot of discussions on mini-splits as well as solar and lithium ion batteries lately.
Bus Grease Monkey just uploaded a fairly comprehensive 20 minute video on his installation on solar panels and lithium batteries including costs, sources and advantages. He even charges his golf cart batteries from his solar. Very informative and worth the viewing.

Regards
Fred

Go to https://www.youtube.com/watch?v=YHX_PQseAf4

luvrbus · July 28, 2020, 08:49:53 PM

He is not breaking new ground ,Solar,batteries and inverters have been beat to death for years on these boards ,anyway you slice the pie no heat or sunshine you better have a backup plan in place and a good one

Fred Mc · July 28, 2020, 08:58:33 PM

No, solar and lithium are not new.But a lot of people are interested in it and always like to hear from someone who has "been there,done that". BGM has been living in his bus completely relying on solar for over 5 months. To me that's a pretty good test of design and equipment.
I'm also on a DIY Solar forum and lots of guys there are designing systems for living in their van/motrohome/trailer and they are talking about having enough power reserve for a few days.This guys has done it for 5 MONTHS.

luvrbus · July 28, 2020, 09:07:40 PM

Quote from: Fred Mc on July 28, 2020, 08:58:33 PM
No, solar and lithium are not new.But a lot of people are interested in it and always like to hear from someone who has "been there,done that". BGM has been living in his bus completely relying on solar for over 5 months. To me that's a pretty good test of design and equipment.
I'm also on a DIY Solar forum and lots of guys there are designing systems for living in their van/motrohome/trailer and they are talking about having enough power reserve for a few days.This guys has done it for 5 MONTHS.

Took him months to get it right if he has gotten in right ,I am just saying there has been plenty before Scott,with solar you follow the sun or you plug into a pole or run a generator wait till winter in TN

lostagain · July 29, 2020, 06:43:00 AM

We use our bus in all conditions, including winter from Canada to Mexico. Solar is great this time of year when the sun is high. We have 700 watts of panels on the roof. In January, you need a good generator, and it has to start reliably at 20 below... No amount of panels and fancy batteries will keep you warm overnight at a rest area in Montana at 8000' in a snow storm, BTDT.

JC

Gary Hatt - Publisher BCM · July 29, 2020, 09:29:24 AM

Quote from: lostagain on July 29, 2020, 06:43:00 AM
We use our bus in all conditions, including winter from Canada to Mexico. Solar is great this time of year when the sun is high. We have 700 watts of panels on the roof. In January, you need a good generator, and it has to start reliably at 20 below... No amount of panels and fancy batteries will keep you warm overnight at a rest area in Montana at 8000' in a snow storm, BTDT.

JC

How well does that solar work up in the Great White North when it is snowing outside JC?

neoneddy · July 29, 2020, 09:46:00 AM

Re: staying warm with batteries and solar at a rest stop. Eh, we kinda did it a few months ago. I ran a 1500w space heater all night to keep us warm and we refilled my ancient AGM telecom bank (22Kw) with solar the next day. Only got down to 30 or so, but I also didn't have the advantage of a hot engine that you get at a rest stop.

If you cover the top like some of us have done, you can do quite a bit on solar. Only issues are when it's hot and cloudy or very cold and cloudy (long term heating isn't feasible on electric of course), we had a rough patch in Montana.. 90s and overcast, busted out the genny.

luvrbus · July 29, 2020, 10:20:20 AM

Solar works good in Arizona since we get 300 days of bright sunshine a year,the boon dockers in Quartzsite get real serious about solar ,I saw a guy on top of his bus washing the panels to gain 1 or 2 watts a day he said when asked

neoneddy · July 29, 2020, 11:14:42 AM

I've seen 10-15% increase in my output by cleaning them. I'm up to 2600 watts of panels, I try and solve it by throwing more panels at the problem.

buswarrior · July 29, 2020, 08:06:07 PM

A well designed and executed bus conversion will adapt to varying conditions.

Putting all the eggs in one basket is asking for problems.

Where in the lower 48 do we not hear cries of anguish when there's a hard freeze? Disabled air systems, frozen plumbing, and now exploding lithium batteries, because someone decides to skip a robust battery management system?

Just more stuff that peeps brag about installing and using, and strangely silent when it goes wrong...

Do proper research, make your own decisions, there's a big difference between doing proper research and copying someone else.

Happy coaching!
Buswarrior

Jim Blackwood · July 29, 2020, 09:37:43 PM

I don't doubt that lithium batteries are very nice... for cordless tools and such where the cost difference is worth it partly because the total cash difference is not that great. But for a bus we're talking about thousands of dollars more here. And I'm not convinced the longer lifespan offsets that. A conventional lead acid battery has always had a lifespan around 5-7 years. The extra weight isn't an issue. Bulk might be but not all that much. And they seem to me to be more tolerant of ignorance. Great for the high roller but maybe not such a good deal for the average bus nut is how I'm seeing it.

Jim

Dave5Cs · July 29, 2020, 09:54:54 PM

The times they are a changing. We have 1500 watts on our Bus roof now and will be working on a battery soon.
Windtrader built his own battery a lot cheaper than buying Liths. His is really small in size but huge in Capacity. Gained a lot of Battery space and is getting ready to install a couple of mini splits that it all will run. I have room for two more panels which will bring me up to 2000 watts at 47.5 Volts and a Victrom Charge controller which will bring that down to 24 volts which my Magnum is. I still have the generator should I need it.

richard5933 · July 30, 2020, 04:01:41 AM

To me the great advantage to lithium batteries is speed of taking a charge. Next is being able to discharge more, resulting in a higher net capacity.

I'd be able to virtually double my capacity in the same space, all while keeping weight the same or maybe even shaving a few pounds.

Weight does matter on a bus, just like any other vehicle. We're pretty much at our upper safe limit right now, so anything new requires losing something old. These things take on weight quickly. For example, we would like to add 4 solar panels to the roof. That will require taking weight off somewhere else. Would be nice to have that happen with a battery swap, but first we need to get the battery heater situation solved.

Jim Blackwood · July 30, 2020, 06:52:21 AM

Quote from: richard5933 on July 30, 2020, 04:01:41 AM
Weight does matter on a bus

I can see where with an older bus the cost might be justified, especially where you are trying very hard to find room to add more weight to the roof in the form of solar cells. But here in the East we get a lot of overcast and I see you guys struggling to get enough wattage to run heat or even the AC, so solar cells still aren't any real bargain here. A 2000 watt heater just won't cut it.

Not so much on the DL. At one point I calculated the payload capacity and it was something like 15,000 pounds after figuring in the weight removed with the seats. Which means battery weight isn't really very much of a concern with these beasties. Might as well take advantage of the lower cost of lead acid.

Jim

luvrbus · July 30, 2020, 07:16:36 AM

Quote from: Jim Blackwood on July 30, 2020, 06:52:21 AM
I can see where with an older bus the cost might be justified, especially where you are trying very hard to find room to add more weight to the roof in the form of solar cells. But here in the East we get a lot of overcast and I see you guys struggling to get enough wattage to run heat or even the AC, so solar cells still aren't any real bargain here. A 2000 watt heater just won't cut it.

Not so much on the DL. At one point I calculated the payload capacity and it was something like 15,000 pounds after figuring in the weight removed with the seats. Which means battery weight isn't really very much of a concern with these beasties. Might as well take advantage of the lower cost of lead acid.

Jim

My 8-D LifeLines are 155 pounds ea x 6 ,the problem I have with ion batteries is the cost for one reason $10 a amp hour vs a dollar for golf cart batteries or $3 dollars for AGM batteries .a big difference for no more than the average owner uses his RV, fulltimers is a different ball game,no way would I invest 10 to 15 grand on a electrical system in a $7500.00 bus make no sense to me