@davemark I recently upgraded my solar system (from an old 1.5kW system to a 6.6kW system). The ROI was less than 3y. The costings for me didn't make sense for either a 13kW system or a system with a battery. For both those systems, the ROI would be significantly longer - for a system with a battery, the ROI was ~ 10 years, at which point I was concerned the battery would have limited remaining life. If I had an EV that I could charge during the day, then the 13kW system would be good.
@davemark We have a Tesla Powerwall 2 and it’s great but apparently the 3 is coming soon. Get microinverters on your solar panels as otherwise, any shade on one will reduce the output on all the panels. And don’t expect to get any significant money from feeding back to the grid - you’re better off using a battery to store that for yourself.
@davemark currently using (and, disclaimer: reviewing) an EcoFlow DELTA 2 Max to almost run my office off-grid and while it’s an awful lot of fun making graphs and stuff I don’t see battery storage being tenable unless you’ve got an extremely unreliable grid, you’re regularly camping/using a mobile home or you live in the middle of a forest in a handmade log cabin and recycle your own pee.
@gadgetoid What about surviving an extended power outage? Say, 2 days long? No snark here, a genuine question. And according to MKBHD, his payback period is < 10 years. He got 3 Powerwall 3 batteries.
@davemark I suppose that’s also a reason- though I’m touching forty and I’ve not seen a power outage for years across three cities, much less one lasting more than a couple of hours. U.K. power infrastructure is on a rather different scale though, and uh- famous last words I guess!
I’m skeptical of a <10 year payback period on what must be- what- $30,000 USD minimum? But then - again - U.K. weather is on a rather different scale. 10 years at my usage is maybe $15,000 USD.
@davemark (I don’t yet have an electric car so that probably accounts for a huge slice of that number, so I take it back- I could believe a <10 year payback if he’s getting close to 100% of his energy from solar or exporting.)
I’m totally new to this stuff and my experiments amount to basically toy setups in the grand scheme of things.
@davemark I'm going down the same road for my own house. The experience from our parents house was to just put in as big of a solar array as your budget allows. Trying to justify sizing based on some financial model for when it will pay off ignores realities like a panel or an inverter rolling over and dying.
So we regret thinking of it as something we needed to justify. We wish we had just installed as much solar as we could in one go instead of maybe coming back and growing it later.
I'm looking at putting in an Enphase solar + battery + transfer switch system
“The capacitive carbon material plays a "buffer" role. When the lead-carbon battery is charged and discharged with frequent instantaneous high-current, the current is mainly released or received by the carbon material with capacitive characteristics”
@davemark There’s apparently something about it similar to ordinary lead batteries are kind of self-balancing when it comes to charging whereas it’s for lithium-ion apparently is really important to have a good charging controller that ensures the batteries are load-balanced correctly.
And I think the cost is cheaper as well. (Although of course not the weight 😅)
There are many YouTube channels on the topic. I follow Wild Wonderful Off-grid. They’ve been off grid for years, tried different approaches, expanded, etc. Its not a channel focus on solar, they are off grid life on their home.
@Dtl @davemark
I have solar and battery. I don't trust Tesla particularly. Plenty of other manufacturers.
You almost certainly won't be able to go 100% off grid unless you have a huge array.
@davemark I have solar panels, but I'm starting to look into an EV with bidirectional charging, so that I can use the EV as a house battery. It sounds like that is about 18 months out, but makes a lot of sense in my use case.
We have LG panels with Enphase microinverters and I've been happy enough with them.
@pdxmisfit Just watched it. Very educational. I wish he would’ve talked about the battery, technology itself, as in, what kind of batteries he has, what kind of tech is in the power wall three. But absolutely a great video. Cheers!
@davemark got solar panels, vendor recommended I used them for a full year before deciding about batteries (do I want them? What size?), which I now believe was great advice. Of course, depends on two main factors:
do you want them to be autonomous
how much is the diff between buying and selling electricity with your provider
I had an off-the-grid cabin completely solar powered. Around 400 watts on the roof with 4 deep cycle RV batteries. 2kw sine wave inverter. Arizona sunshine. Never ran out of power.
@davemark We just did solar, but decided against batteries for financial reasons.
Solar generates power, which essentially generates money. But batteries don’t generate anything — and in our area, net metering with the power grid is free.
We couldn’t justify the expense of batteries, but if you need more reliable power than your local grid can provide, they might be worth it for you.
@davemark We got a non-Tesla Sunpower battery, don’t know how well it will work in a power outage. We figure keeping a little light and refrigeration would be good.
@davemark I will say, I generally try to steer people away from Tesla stuff, because service/replacement can be all over the map. Always look for a local-ish company for your install and check reviews. You want not just the initial install to go well, but also be able to get decent service if something happens. The service part is where most people have terrible experiences because the industry isn't set up for that yet. Good service people exist, but we're few and far between.
@davemark I just installed a solar system based on Enphase microinverters. I’m considering the grid to be my battery until the next gen of storage tech comes out. The $/kwh storage wasn’t attractive for me and I think there’s a breakthrough coming to market soon.
@davemark You won’t regret it. Check out this channel. It is excellent. You might want to watch the last video about batteries. Rumours of new Tesla Powerwall as they are quite old now.
@davemark@bazcurtis I watched one of the Gary Does Solar videos and it raised all sorts of red flags.
The one I saw had to do with sizing the battery pack. Not only did it read like an ad for Octopus Energy, it ignored the cost of the battery pack being used for the comparison.
One thing to be aware of is what will be covered by your insurance and power company. In my area, the power company will not allow net metering if you generate more than 115% of your annual usage.
@davemark@bazcurtis My homeowner’s insurance won’t cover solar panels that provide more than 115% of your annual usage, too. I haven’t looked into how large of a battery pack that will covered.
@the_other_jon@davemark I post my daily statistics via @bazcurtissolar. Imported from the grid, battery charge, grid export as well as the relevant costs for those.
@bazcurtis@davemark@bazcurtissolar I think I would prefer your type of charging to net metering because it incentivizes you to conserve when the price is high.
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