Full-time A/C on Lithium While Driving Results

[ChrisCow]

I have a 2018 AI GT which I had AM Solar upgrade to 400 watts of solar plus 600 aH of lithium. I live in and travel frequently in the southwest, which can be scorchingly hot. If you carry passengers, it can be very hot in the back for them.

I did an experiment to determine how long I could run the A/C on the lithium while getting some juice from solar and the factory alternator. I drove from Tucson, AZ to Palm Springs. I set the A/C to 70 degrees and let it run full blast 100% of the time, even during rest stops with the engine off. I left Tucson at 10:30am and parked in Palm Springs at 7:50pm. It wasn't THAT hot of a day, only getting up to 88 degrees but it was also quite overcast so I didn't get a lot of solar benefit.

Any guesses on how it went? I can tell you it was ice cold in the back. My passengers definitely complained

Here are my results:

10:30am - departure

• Batteries: 97%
• DC: -1588W (negative means flow INTO batteries)
• Solar: 134W
• AC: 1537W

1:50pm - 3rd stop in Phoenix (errands)

• Batteries: 87%
• DC: 192W (engine not running)
• Solar: 201W
• AC: 1536W

4:00pm - rest stop in Tonopah

• Batteries: 70%
• DC: -1317W (engine running)
• Solar: 107W (overcast)
• AC: 1511W

6:45pm - rest stop in Indio

• Batteries: 81%
• DC: -1202W (engine running)
• Solar: 5W (getting dark)
• AC: 1408W

7:50pm - Palm Springs

• Batteries: 85%
• DC: 245W (engine stopped)
• Solar: 0W (dark)
• AC: 1352W

Short video of the load as of Indio:

https://www.youtube.com/watch?v=ItiP7OSx1y4

[wachuko]

Encouraging results for those of us thinking about this.

Thank you for sharing!

[InterBlog]

I didn't catch (or I don't recall) where you had gotten this conversion done (possibly it is in another thread), or who did it.

Be aware of the potential for alternator issues when engaging in continuous engine charging due to high lithium drains. My blog post on this topic:

PSA: ALTERNATOR CLUTCH PULLEY FAILURES ON LITHIUM SYSTEMS

[Boxster1971]

Originally Posted by InterBlog

I didn't catch (or I don't recall) where you had gotten this conversion done (possibly it is in another thread), or who did it.

Be aware of the potential for alternator issues when engaging in continuous engine charging due to high lithium drains. My blog post on this topic:

PSA: ALTERNATOR CLUTCH PULLEY FAILURES ON LITHIUM SYSTEMS

It was done by AM Solar as mentioned in the first post.

CHRISCOW - this is good advice from INTERBLOG. The stock OEM alternator will not survive long with this kind of use.