Earlier quoted context omitted.
Can you point out what part of what I said is factually inaccurate?
https://magnifina.com/articles/rooftop-solar-yield/ explains it better than me attempting to write a wall of text.
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What a year of solar and batteries saved us in 2025
181–190 of 368 posts
Re: What a year of solar and batteries saved us in 2025
#182Earlier quoted context omitted.
Who spends $50K on heat pumps? They're not anywhere near that expensive.
I'm talking about geothermal water/water installs for central heating. No one is heating their place with air/air heat pumps besides americans who haven't figured out that heating spaces via air is shit tier in term of comfort and efficiency
>No one is heating their place with air/air heat pumps besides americans
I am, and I am not an american, lol.
Re: What a year of solar and batteries saved us in 2025
#183It's crazy how power hungry UK homes are, or maybe it's UK power consumption habits in general. I use about ~300 kWh/month. A little bit more with AC some times of the year. What are you even powering with 15000 kWh?
Are you commenting on this article? This person is in the UK. You can see it on their domain, their calculations using pounds, and then mention living in the UK multiple times in the "Our setup section".
Re: What a year of solar and batteries saved us in 2025
#184Earlier quoted context omitted.
Their total household usage was actually ~17.3 MWh depending on what data source you're using for their usage. Given 6 MWh of exports with only 3.2 MWh of total solar production, they are cycling their powerwall to get paid for the fact that their off-peak rate is half the price of their peak export tariff rate which is inflating the number you're looking at.
That is still an enormous amount of electricity for a single family to consume.
He mentions that he has a server. It wouldn't surprise me if that consumes the majority of that.
Re: What a year of solar and batteries saved us in 2025
#185Where I am in California, there's a $30+/mo charge to connect to the grid, and the largest savings from a battery was being able to disconnect from the grid. There's lots of time I have excess power generation when I could give to the power grid, if I were connected, but I would have to pay extra to do so, so the potential goes unused.
The reason is that California has made their grid extremely vulnerable. The grid already heavily overproduces solar so it is reasonable to have negative prices. There is no sink available.
Re: What a year of solar and batteries saved us in 2025
#186Earlier quoted context omitted.
That's fair. Better comparison: Author's config: 3x Powerwalls + inverters = 40 kWh 4.2 kW array £39,360 = $53k USD Alternative: EG4 18kPV Hybrid Inverter = $5000 3x RIUXU = $9600 10x Trina Solar 435w panels = $1580 Cabling, installations, etc. = $5000 Total = $21k It's not even close...
This is still not an accurate comparison. I'm not a Tesla fanboy but of all of the major players in the non-diy game (Enphase, Franklin, Tesla, Sol-Ark) they provide the best value for money, and are impressive pieces of equipment. The EG4 18k has 11.5 kw backfeed capability, with a rather pathetic 65ish amp in-rush. Obviously 18kw usable solar capacity(they technically let you land up to 21kw, but only 18 is usable)…
None of those things matter when your solar array is 4.5 kW and you have a standard 150A/200A grid in....
Like I said, they basically are not sold to scale like a normal household uses electricity.
EDIT: What the heck is in-rush and backfeed? Are you talking about AC input to charge the batteries? The 18k is 50A @ 240VAC (12kW) fyi. Also, why does the charge rate even matter there? For the AC output its also 12 kW...the family is average 48 kWh days, which is 2 kW hourly average...
Re: What a year of solar and batteries saved us in 2025
#187Earlier quoted context omitted.
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.
In CA it can be 0 but not negative. Depending on when you signed up for NEM you may have a guaranteed floor like 4¢/kWh or even much more.
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Re: What a year of solar and batteries saved us in 2025
#188It'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…
I think "overpriced" depends a lot on what problem you're trying to solve
Powerwalls don't uniquely solve any problems other brands can't do.
Re: What a year of solar and batteries saved us in 2025
#189Earlier quoted context omitted.
Having one place to handle humidity, temperature, and exchange of fresh air makes ductwork the king of comfort and efficiency.
Separation of concerns is the king of avoiding pricy maintenance and headaches. You can already do most of that with a passive heat recovery ventilation system coupled to a ground/water exchanger. All systems are independent and the most high tech equipments you need are fans and a water pump
It’s a tunnel for air.
Only using ductwork for heat recovery ventilation without also using it for heating and cooling means more complexity, instillation costs, and maintenance issues etc. Further moving air allows you to use dramatically less material for heat exchangers.
Net result higher efficiency, fewer things that can break, fewer locations something can break, and lower risks of water damage to your home etc.
Re: What a year of solar and batteries saved us in 2025
#190Earlier quoted context omitted.
It is essentially a bond return, with the caveat being that solar PV panels will last 25+ years with some degradation and reduction in output. To your point, the best arrangement (imho) is a standing seam metal roof (40-70 year lifetime) with the panels mounted via friction racking with no roof deck penetrations. This avoids the economic cost of pulling everything off the roof to re-roof, and should outlive any homeo…
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> while the initial principal of your bond investment will remain intact.
As long as the bond issuer remains solvent. How much do you trust bonds that yield 9% to retain their full value for 25 years?