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What a year of solar and batteries saved us in 2025

scotthelme.co.uk

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Re: What a year of solar and batteries saved us in 2025

#221

Post by secabeen »

Veserv wrote: post #216
1980phipsi wrote: post #146

Earlier quoted context omitted.

Any idea why swapping didn't pan out for Tesla? My understanding is they are doing that in China.

What do you mean? It did pan out for Tesla. Faking a single demo granted them 75% more ZEV emissions credit government subsidys [1]. That increased their profits by hundreds of millions of dollars. All they had to do was go on stage and “swap” a battery without any clear video of the process and never “demonstrate” it ever again. This is a company known for faking prominent demos like the FSD demo (where it crashed i…

Battery swap was and remains really risky for anyone doing it. You're taking a $10k asset, and swapping it for another $10k asset of unknown provenance. Does anyone really want to be in a situation where they purchase a new Tesla with a brand new, max-range battery pack, then swap it once on a road trip and get one that's been used for 300k miles and is at 75% of original capacity?

Re: What a year of solar and batteries saved us in 2025

#222

Post by greycol »

jillesvangurp wrote: post #165
mbesto wrote: post #52

It's wild how overpriced Tesla Powerwalls are. 16 kWh battery with all of the UL supported listings etc = $3300 [0] 13.5 kWh Tesla Powerwall is $12k~$15k You would get your return way back quicker. [0] - https://www.ruixubattery.com/product-page/lithi2-16-battery-... EDIT: As others have pointed out, powerwalls have inverters built in so it's not totally apples to apples. You can get a beefy inverter for $5k and it's…

There's going to be a bloodbath in that market in the next years. There are a lot of battery producers and most of them are not producing at full capacity. At the same time, manufacturing cost is dropping as well. Some battery makers are producing batteries at a cost level of around 60$ per kwh. At that cost, the 16kwh battery would come out below 1000$ (not the same obviously as the product price). Sodium ion might…

One thing to remember is as it becomes more widespread line costs will go up (assuming they are subsidized by kwh use, which they generally are) and no-sun power prices will increase as it's the only time when the grid needs power from non solar producers and they still need to cover cost incurred while they're not producing.

That will push the economics towards completely off grid systems as more people adopt solar, so if people are planning it for themselves they should probably consider that it will make sense to expand their set up in the future and that there might be a price crunch due to higher demand because of larger systems coupled with more people wanting to switch.

Re: What a year of solar and batteries saved us in 2025

#223

Post by Aurornis »

tomashubelbauer wrote: post #53
Barbing wrote: post #41

Earlier quoted context omitted.

Awesome. Feel you have more unknowns on the safety front? vs. the expensive off-the-shelf. [in the USA, it’d also be “fewer names to sue” in that unlikely tragedy of combustion in home, but no euro /kWh targets there]

LFP batteries are as likely to burn down your house as a stack of wood is. I'd be worried about the inverter or botched DIY wiring (especially not to spec torque on terminal connections and botched crimps leading to hot spots), but not about the batteries themselves. For a person who wants to save some money, but doesn't know how to work with electricity, the best move is probably to get cheap LFP cells from China, b…

> LFP batteries are as likely to burn down your house as a stack of wood is.

LFP batteries are much safer than past chemistries, but this statement is way too broad.

High power batteries are always more dangerous than something like a stack of wood, because batteries will gladly dump their entire energy capacity very rapidly into a short.

Even if the battery itself [mostly] won't self-immolate, the entire installation can be a fire hazard.

Treat them with proper respect.

Re: What a year of solar and batteries saved us in 2025

#224

Post by shawabawa3 »

secabeen wrote: post #221
Veserv wrote: post #216

Earlier quoted context omitted.

What do you mean? It did pan out for Tesla. Faking a single demo granted them 75% more ZEV emissions credit government subsidys [1]. That increased their profits by hundreds of millions of dollars. All they had to do was go on stage and “swap” a battery without any clear video of the process and never “demonstrate” it ever again. This is a company known for faking prominent demos like the FSD demo (where it crashed i…

Battery swap was and remains really risky for anyone doing it. You're taking a $10k asset, and swapping it for another $10k asset of unknown provenance. Does anyone really want to be in a situation where they purchase a new Tesla with a brand new, max-range battery pack, then swap it once on a road trip and get one that's been used for 300k miles and is at 75% of original capacity?

As long as you can always swap your battery again I don't see the problem

As long as the average battery health in the system is like 90% and the minimum is say 80% why would you care if you're getting a new battery every few days?

If anything it removes a big cause of depreciation from your car

Re: What a year of solar and batteries saved us in 2025

#225

Post by modeless »

mbesto wrote: post #52

It's wild how overpriced Tesla Powerwalls are. 16 kWh battery with all of the UL supported listings etc = $3300 [0] 13.5 kWh Tesla Powerwall is $12k~$15k You would get your return way back quicker. [0] - https://www.ruixubattery.com/product-page/lithi2-16-battery-... EDIT: As others have pointed out, powerwalls have inverters built in so it's not totally apples to apples. You can get a beefy inverter for $5k and it's…

The crazy thing is you can buy a 69 kWh battery from Tesla for $36,990, and it comes with a whole car too.

Re: What a year of solar and batteries saved us in 2025

#227

Post by coryrc »

culebron21 wrote: post #226

How does a household use 1,500+ kWh per month? At my home, we sometimes get above 200, in summer with AC we may score 300 kWh, but how do you consume 5x of that? Is it heating?

Is your heating electric and do you have two electric cars?

Re: What a year of solar and batteries saved us in 2025

#228

Post by Ensorceled »

ishtanbul wrote: post #202
Ensorceled wrote: post #138

Earlier quoted context omitted.

Are you sure? Lots of people are telling me that batteries only last 4-5 years tops and solar panels usually burn out before 10 years /s I particularly love when they are telling me that my 11 year old Prius' batteries will only last 5 years before they are junk.

This is totally wrong. I work in the industry. Solar panels should last for 30 years, but they degrade in capacity by 0.5 to 1% per year, depending on environmental conditions (temp, radiation, etc). Lithium batteries from tier 1 suppliers can last at least a decade of regular use. It depends on how their cycling and state of charge is managed. If you keep them between 20% and 80% charge, they can last incredibly lon…

/s is the sarcasm tag.

Re: What a year of solar and batteries saved us in 2025

#229

Post by coryrc »

BeetleB wrote: post #42
lm28469 wrote: post #27

Earlier quoted context omitted.

It's high but it really depends on your lifestyle and appliances. If you have a heat pump water heater and heat pump based floor heating you'll use 1/4th of the energy as the same house with resistive water/floor heating. A house which barely passed regulation from 2010 will consume 5-10x the energy of a certified passive house. etc. That being said I think you have to draw the line somewhere. I'd much rather have in…

Who spends $50K on heat pumps? They're not anywhere near that expensive.

A lot of people in America, sadly. Mini splits cost $250 to install in Japan and frequently $10k/head in the USA.

Re: What a year of solar and batteries saved us in 2025

#230

Post by coryrc »

systemtest wrote: post #125
coryrc wrote: post #106

Earlier quoted context omitted.

The worst that happens is you get paid back at the wholesale rate (from your bill, not live market price) instead of discounting kwh-per-kwh.

But is that rate always positive? Where I'm from during peak sun hours, the rate is negative and you end up paying money to deliver money to the grid. They do this to incentivise you to decouple your solar installation during peak sun hours so the net doesn't get flooded with too much energy.

Yes, you asked about California. I assume you are not in California.
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