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All the electricity you'll need for 40 years

innerpathing.com

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Re: All the electricity you'll need for 40 years

#91

Post by bdhdbebebeb »

toast0 wrote: post #89
noahjk wrote: post #83

Earlier quoted context omitted.

This is the only reply I understand, so I’ll follow up here - in this case, is the end user paying to push the energy into batteries that the power company owns? Or is the extra energy just dissipated somewhere? Or does the power company stop producing their own energy once the grid is saturated? (I believe that electricity doesn’t actually flow like water, so it’s not the exact same electrons that the solar panel is…

When there's too much energy available for the grid, and the price goes negative, producers are paying for someone to use that energy or paying another potential producer to reduce their output. Some industrial users have variable demand, and a lower (or negative) price could encourage them to use more. A multi-region internet service might send more traffic to a datacenter with negative electricity prices, even if i…

What happens if no one takes the power (not one solar installation but lets assume lots of surplus power). Does it screw up the grid? Increase voltage/frequency?

Would this lead to grid needing to be shut down?

Re: All the electricity you'll need for 40 years

#92

Post by StrangeDoctor »

toomuchtodo wrote: post #24
candiddevmike wrote: post #3

This seems like a "green brag" without much substance. Great that this person is privileged enough to afford solar panels, I guess. Nothing to be learned here though: no wire diagrams, placement schematics, or BoM. Just someone telling everyone how green they are.

The idea is the important part. The details (wiring schematics and so on) are not. The cost of solar is rapidly approaching where you’re prepaying for your energy for the rest of your life with a few thousand dollars. You can get solar panels for 10 cents/watt today, for example. That price will potentially continue to decline (historically, price has declined ~20% for every global doubling of PV manufacturing capaci…

I think the details are actually important to the idea. Mainly this green brag doesn't seem to add up. The battery system is crucial.

While there's a bit about needing to replace it in 10-20 years coming out to a $83/month, this is essentially burying the $15,000 bill coming.

Also, unless their battery system is wildly over provisioned at the moment, you can't just add a bunch of new panels. Are they selling back to the grid? I don't think so, they mention grid independence wrt natural disaster. Do they have some sort of system to heat the water in the day only? Did they just take the name plate capacity of the system and multiply it by 40 years? who knows?

These "details" will make anyone buying into their big idea quite frustrated.

I also don't understand the part about chopping wood. Yes it's probably a idilic bit for the story, but that's almost one of the worst fuel sources. Dangerous, carcinogenic, and polluting.

edit: yes in the footnotes, burning wood. Getting rid of that would be the number one way to improve their impact on the earth and their community.

Re: All the electricity you'll need for 40 years

#93

Post by TrueSlacker0 »

skybrian wrote: post #28

> Electric vehicles are mainstream and last longer than their gas engine counterparts, with an estimated lifespan of 200,000 miles. What's this based on? Don't many gas cars last that long? It seems like it depends very much on how well you maintain them.

I also thought this was an odd statement to see. Electric cars really haven't been around long enough to give that kind of respect to time. A few brands have but the newer models are totally different beasts.

Vs ice which easily last long, long past 200k. I'm at 240k right now and it still performs perfectly.

As a side note on the newer ice vehicles I don't see how those terrible tablets that control everything will last long enough for the other mechanical problems in the cars to show up.

Re: All the electricity you'll need for 40 years

#94

Post by quickthrowman »

sdk77 wrote: post #29
itishappy wrote: post #23

Earlier quoted context omitted.

> ... in summer I might need to pay to feed in the surplus. You're allowed to just disconnect solar panels. It's free and does not damage them.

Sure. Of course. Not being allowed to disconnect them would be ridiculous. But do you want to keep an eye on the market every day, and run to the breaker to turn on an off your inverter? No. So you need a solution for that. Then a battery is much more interesting.

You could implement something pretty easily with a relay or contactor and an ESP32 and a way to monitor the spot price, or just buy a system with that feature already built in.

Re: All the electricity you'll need for 40 years

#95

Post by BobbyTables2 »

jeffbee wrote: post #53
candiddevmike wrote: post #3

This seems like a "green brag" without much substance. Great that this person is privileged enough to afford solar panels, I guess. Nothing to be learned here though: no wire diagrams, placement schematics, or BoM. Just someone telling everyone how green they are.

I agree about this article being vapid, but at least it does introduce the fact that PV doesn't degrade. A lot of people have been poisoned by oil industry propaganda that every PV panel needs to be trashed in 20 years.

Aside from propaganda, what if the roof only lasts 25 years?

And doesn’t mounting panels on top of a roof increase possibilities for leaks?

I really would like solar to work. But have seen too many crazy storms and even a minor tornado in the past 5 years to make me wonder about 20+ year longevity.

Re: All the electricity you'll need for 40 years

#96

Post by noahjk »

orwin wrote: post #84
noahjk wrote: post #83

Earlier quoted context omitted.

This is the only reply I understand, so I’ll follow up here - in this case, is the end user paying to push the energy into batteries that the power company owns? Or is the extra energy just dissipated somewhere? Or does the power company stop producing their own energy once the grid is saturated? (I believe that electricity doesn’t actually flow like water, so it’s not the exact same electrons that the solar panel is…

[edit] if you don't produce the exact amount consumed at the exact same time, the current will loose its phase and the effective energy transported will be reduced, while producing surtensions at different grid points (don't quote me on that, but accumulator try to keep the phase, and too much divergence can cause their failure from what I understand. But I'm no physic major and I might be completely wrong). Grid coo…

Interesting!

Is there a reason that consumer solar can’t be accounted for as smaller stable nodes in the system (sounds like they are still considered volatile and not a reliable source of inflow power)? For instance, maybe a rooftop solar array can easily be sucked up if the home decides to do a few loads of laundry that day, and therefore since there aren’t enough homes with solar arrays, it’s harder to predict an average influx per day from consumer solar to power the grid?

Are there any goals to shut down larger plants or not build larger solar fields by instead subsidizing distributed solar on peoples’ property?

Utilities are so interesting. The other afternoon I was looking out at the hills as the trees change, and said to my friend, “what a beautiful view… besides all these power lines! Although, I’d rather have the infrastructure than an unmolested view…”

Re: All the electricity you'll need for 40 years

#97

Post by jeffbee »

BobbyTables2 wrote: post #95
jeffbee wrote: post #53

Earlier quoted context omitted.

I agree about this article being vapid, but at least it does introduce the fact that PV doesn't degrade. A lot of people have been poisoned by oil industry propaganda that every PV panel needs to be trashed in 20 years.

Aside from propaganda, what if the roof only lasts 25 years? And doesn’t mounting panels on top of a roof increase possibilities for leaks? I really would like solar to work. But have seen too many crazy storms and even a minor tornado in the past 5 years to make me wonder about 20+ year longevity.

I would personally never mount panels on the roof in a context like this one, a house in the middle of nowhere. They should just be on a pole, mast, or frame. Anywhere but the roof.

Re: All the electricity you'll need for 40 years

#98

Post by toast0 »

bdhdbebebeb wrote: post #91
toast0 wrote: post #89

Earlier quoted context omitted.

When there's too much energy available for the grid, and the price goes negative, producers are paying for someone to use that energy or paying another potential producer to reduce their output. Some industrial users have variable demand, and a lower (or negative) price could encourage them to use more. A multi-region internet service might send more traffic to a datacenter with negative electricity prices, even if i…

What happens if no one takes the power (not one solar installation but lets assume lots of surplus power). Does it screw up the grid? Increase voltage/frequency? Would this lead to grid needing to be shut down?

Yes, if nobody removes the excess, grid frequency will increase. Running too high or too low frequency can damange equipment, on both the supply and demand sides.

Re: All the electricity you'll need for 40 years

#99

Post by fred_is_fred »

nightski wrote: post #73
Animats wrote: post #68

Average US home power consumption: 30 KWh/day. Assuming an average of 4 solar hours per day, you would need a solar system capacity of approximately 7.5 kW to 12.5 kW. Individual solar panels produce 250-400 watts. So, conservatively, 50 panels. Installed, that's currently about $25,000, including inverter but not battery backup. Battery backup will cost maybe $15,000 more. So, the whole installation is about $40,000…

In my state electricity costs about $0.089/kWh. We spend about $100/mo on electricity total which comes out almost exactly to your 30kWh/day figure (with a $23.15 connection charge included). Invested that 40k would conservatively cover over 2x our electricity bill without touching the principal (inflation adjusted). That's a pretty hard sell for solar. Obviously incentives will improve things but it just seems less…

That’s where my math went. 30k- 12 years to get back to the investment. 30k in the s&p is worth a lot more than 30k…

Re: All the electricity you'll need for 40 years

#100

Post by Animats »

ifdefdebug wrote: post #81
Animats wrote: post #68

Average US home power consumption: 30 KWh/day. Assuming an average of 4 solar hours per day, you would need a solar system capacity of approximately 7.5 kW to 12.5 kW. Individual solar panels produce 250-400 watts. So, conservatively, 50 panels. Installed, that's currently about $25,000, including inverter but not battery backup. Battery backup will cost maybe $15,000 more. So, the whole installation is about $40,000…

Your numbers are way off (at least for Europe). Panels are 580 W peak now and cost < €150. Battery < €1000 per kWh. Prices still dropping.

I was quoting an installed price. Panels are less than half the installed cost now.

If the "solar roof" people ever get their act together, that might change.

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