HN Explorer

Ask HN: Do you have home solar?

50 points by mmayberry ↗ HN
Hi! I'm one of the co-founders of Jasmine Energy (YC S22) and I'm looking for people who have installed solar panels on their home. If thats you, would you be open to sharing the documents you received from your installer? We're working on a new tool at Jasmine Energy that may be able to help you find rebates and incentives buried deep in those documents.

48 comments

[ 4.8 ms ] story [ 97.0 ms ] thread
novateg
I have home solar. I'm interested
mmayberry
Thank you. Just sent you an email
sharpshadow
Germany is steadily reducing the legal hurdles to install balcony solar plants. Now one does not have to ask the landlord for permission, no tax, 800W allowed, etc..

Berlin grants one 500€ with the purchase of a balkony solar plant.

idontwantthis
Do you run it as it’s own circuit or do you connect it to your main power somehow?
sharpshadow
Own circuit, main power, feeding it back to the grid for profit, feeding it back to the grid for free are possible options. The options come with additional costs.

In the latest round of new regulations they allowed the use of 230V Schuko plugs for balkony plants.

idontwantthis
That’s wild. There’s no way I could ever do that with a condo or rental house in the U.S. I would never get to touch main power.
jupp0r
I think all you do is connect the inverter to any wall outlet. Basically a male-to-male power chord.
mikestew
Surely it is something safer than a suicide cord,[0] especially if used inside where things like children live.

[0]https://www.consumerreports.org/home-garden/generators/why-s...

phiresky
It's a male end on the PV side, but every of these plug-in inverters I've seen only start outputting when they get the 220V 50Hz input, so they are inert as long as they are not plugged in. As far as I know they always rely on the grid frequency.
jeeeb
This is necessary to prevent islanding.

If the inverter outputs when the grid has lost frequency then other inverters can respond by also starting to output. This creates a chain reaction and can generate serious currents in sections of the grid that are expected to be on outage, which is a safety hazard.

ssl-3
Grid-tied solar inverters, as a general rule, do not (cannot) output any power at all in the absence of grid power.

The act of plugging in a normal grid-tied solar inverter with a regular ass-plug[0] is just exactly as safe as plugging in any other electrical appliance is.

(There are other concerns, but the physical plug is not amongst them.)

0: https://xkcd.com/37/

ssl-3
It can be that simple in 240v-ish countries, where everything in a home is connected to the same two transformer taps outside.

Just install a dedicated branch circuit (or otherwise isolate it so that nothing else is using that branch), plug it in, and all the stuff in the house is indiscriminately somewhat powered by solar.

And...done. That's all there is.

Here in the States, things are a touch more difficult: Our normal residential power is 240v, but our regular branch circuits (and outlets) are 120v by using a center tapped secondary winding on the transformer as neutral.

So to power a house's stuff indiscriminately in the US with a plug-in inverter (or two) would require two different outlets that are each on different transformer taps, or a 240v outlet.

Using a singular regular 120v outlet in the US will only cover about half of the regular stuff in a house, and will never be able to power any 240v loads.

(And, yeah, we have standardized 240v outlets. But they're almost never found in a home except behind major appliances like the clothes dryer and/or electric range. We also have standards for smaller outlets that would be suitable for small appliances like a toaster or a kettle, but they're almost non-existent in the wild.

It'll be a long while before we get approved plug-in grid-tied solar here.)

Maskawanian
If the sine waves don't line up, you are in for a very bad time. There is a reason crossover switches exist, please never do this.
moooo99
That won’t happen since the inverters are all tied to the grid frequency
Maskawanian
You think they are, but you have to trust that this happens. And even if they are, what happens if the grid is offline and comes online while the inverter is operational, how long does it take, if it does at all, to adjust itself.

If the product doesn't explicitly state this on its packaging there is absolutely a chance for competing sine waves. If this wasn't the case, transfer switches wouldn't have been invented. The original comment I replied to is simply dangerous.

jupp0r
There is circuitry to prevent this.
animal531
Here in South Africa our main electricity supplier has been failing for the last few years due to corruption, nepotism etc.

As a result solar power has really taken off for both businesses and homes.

dbetteridge
800W ... total?

I guess for apartments thats better than nothing, but wouldn't it make more sense to install them on the roof of the building and tie it into rebates for everyone?

sharpshadow
It’s for people which rent or own an apartment with balcony. Landlords and home owners can still install panels on the roof.

There are options to invest in solar farms which start to yield returns after some years.

prdonahue
I do, feel free to DM on Twitter. Just pull an 18 kW system in a few months ago and it’s been great.

(Full disclosure: I’m in the solar industry, but on the software side. Recently left Cloudflare to join Aurora Solar as CPO.)

Yawrehto
No, but when the roof eventually needs repair we probably will. Sounds like an interesting idea though!
theogravity
I had my panels installed in 2018. I doubt there's any incentives at this point? Are you looking for more recent installs?
megablast
I only have solar!! It’s awesome. Completely off grid. Sailboat life.
orwin
Do you use gas stove for cooking? Or is it also electric?
ryandrake
I've got a pretty old 7400 watt system installed back when the incentives from California were pretty good. It's lost quite a bit of efficiency over the years, and usually tops out at around 5200 watts, providing ~40KWh during cloudless days in the summer. I don't know much about net metering and incentives, but what I do know is that I can't make any major changes to the installation without ratcheting down to the current regulatory system, which reduces compensation for selling during off-peak hours.
mmayberry
if you have any paperwork related to your installation we would love to see it. The standard installation pack (diagrams, blueprints, system info, tech specs, etc...) is what we are most interested in. You can drop anything you are comfortable sharing here: https://driveuploader.com/upload/UdA5Ev9YFP/
pfd1986
OT but what's the best way to find incentives and rebates given a zip code? Google just suggests 1,000 ads...
nick238
https://sunroof.withgoogle.com/ kinda works, but strangely if I try it on my house in Chicago, it omits the state rebate. Illinois/local utilities cover 20-40% the installation cost, depending on how well they produce. After the ~30% tax rebate from the feds, basically halves the "price after incentives".

TBH, best way is to talk to a solar provider. They're not as hard to stop talking to as Mormons.

tdaltonc
DSIRE (Database of State Incentives for Renewables & Efficiency) is the database that all of those companies use.

https://www.dsireusa.org/

Disclosure: I'm also a Jasmine cofounder.

metadat
Plz shoot me an email, collect.metadat at gogglestermale.

P.s. this thread would've been less noisy if there was a decodable email address in your profile, sweetie pie. :)

Then again, maybe you know the trick where more comments is mo' betta'. No judgement, haha.

metadat
FWIW, OP never bothered to contact me.

Not everyone uses twitter and slides into the DMs like that.

Best wishes,

Metadat

Edit: please do downvote this benign message to your heart's content, cheers

chrsw
Do incentives and rebates apply to batteries as well?
kkfx
I do, self-made (legal here, France), composed of:

- 12x Trina Solar Vertex S 400Wp (TSM-400DE)

- solar inverter Fronius Primo 5kW

- battery inverter Victron MultiPlus II-GX

- 8kWh LFP BYD LVS

- smart meter (zero injection setup) Victron/Giavazzi ET112

- EV charging piloted by the Victron (EVC300400300)

There was not much 400V batteries and inverters back than. I log a bit via Home Assistant, so far without InfluxDB simply because I still have to find value in logging over longer time period, pruning data etc and HA alone was time consuming to setup due to the devs passion for YAML (GRRR i HATE modern YAML mania).

Personally in commercial terms I'm DISGUSTED by the current state of thing where in China prices plunge and here in EU skyrocket, as quotes from professional installers are so high that a not-self-made system is simply economically not a good investment.

Feel free to ask what you want :-)

paultannenbaum
I put solar on my roof right before the NEM 2.0 -> 3.0 switch over. Email is in my profile.