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I looked into this living in Japan and tired of the electric bill after running AC 24/7 for three months when it's 35 degrees at 65% humidity. $5500 in solar p

I looked into this living in Japan and tired of the electric bill after running AC 24/7 for three months when it's 35 degrees at 65% humidity. $5500 in solar panels including a battery would be just enough to keep the AC on all summer, and that's being fairly high on the temperature, around 26. So based on cost alone and not power draw, with the AC off you could comfortably power a fridge, PC, and water heater, I guess? But I'm talking out my ass here

anukin 20d ago
I have done a grid based setup at my house in India and it cost us close to 3k for a 5kw setup with 4 acs. Planning for a complete off grid solution once the efficient panels like hjt and sodium cells become common place. Right now we have acid batteries and they are not very comfortable to handle.
lefra 20d ago
Converting Sun to electricity to power a water heater is suboptimal. The water can be heated directly by the Sun. If you can put a water tank above the solar panel, you don't even need a pump.
- ericd 20d ago
  If it powers a heat pump water heater, it's pretty efficient, and much less plumbing involved.
- ButlerianJihad 20d ago
  This is true. https://en.wikipedia.org/wiki/Solar_power_at_the_White_House#Carter_administration https://en.wikipedia.org/wiki/Solar_power_at_the_White_House... It is also true that solar water heating has unpleasant failure modes.
- 3eb7988a1663 20d ago
  From a purely efficiency standpoint, yes, but practically, electricity->heat is a lot cheaper to install. Plumbing is messy, and bolting on a water circulation system to a roof is harder than delivering more joules over the wires.
  - JumpCrisscross 20d ago
    Having gone through one ice-dam related roof leak in the past, I'm also not thrilled with the idea of superheated liquids hanging out casually above my bedroom while I sleep.
fy20 20d ago
I live in a 160m2 (1700 sqft) house in Northern Europe (54N). 10kWp of solar on my roof generates around 1/3 more than I consume over the year. Everything is electric, I don't have natural gas. I have a heat pump for heating and cooling (rarely gets above 30c here). If I had a battery April - September could all be local consumption (I pull around 5kWh from the grid each day). The issue is winter: It gets down to -25c and there is very little sun (not that it would help due to snow on the panels). In January and February this year I generated a grand total of 5kWh :D However my house is a new house, it's designed to modern building standards and has 30cm of PIR insulation in the walls and even more in the roof. There's just no way to properly renovate old buildings to be like that without basically rebuilding the whole thing. The actual cost of materials is not expensive though (for the west). In milder climates (UK I'm looking at you) there's really no reason all new houses cannot be net-zero.
- t0bia_s 20d ago
  Modern building standard constantly changes. Time will show, how good they are. Meanwhile, we have, in Europe a lot of buildings from late 19, early 20th century that are perfectly habitable today and often are ruined by modern standards that not respect old standards. For example basement addition that prevents the apartments from “breathing” and causes them to become damp.

anukin 20d ago

I have done a grid based setup at my house in India and it cost us close to 3k for a 5kw setup with 4 acs. Planning for a complete off grid solution once the efficient panels like hjt and sodium cells become common place. Right now we have acid batteries and they are not very comfortable to handle.

lefra 20d ago

Converting Sun to electricity to power a water heater is suboptimal. The water can be heated directly by the Sun. If you can put a water tank above the solar panel, you don't even need a pump.

ericd 20d ago
If it powers a heat pump water heater, it's pretty efficient, and much less plumbing involved.
ButlerianJihad 20d ago
This is true. https://en.wikipedia.org/wiki/Solar_power_at_the_White_House#Carter_administration https://en.wikipedia.org/wiki/Solar_power_at_the_White_House... It is also true that solar water heating has unpleasant failure modes.
3eb7988a1663 20d ago
From a purely efficiency standpoint, yes, but practically, electricity->heat is a lot cheaper to install. Plumbing is messy, and bolting on a water circulation system to a roof is harder than delivering more joules over the wires.
- JumpCrisscross 20d ago
  Having gone through one ice-dam related roof leak in the past, I'm also not thrilled with the idea of superheated liquids hanging out casually above my bedroom while I sleep.

fy20 20d ago

I live in a 160m2 (1700 sqft) house in Northern Europe (54N). 10kWp of solar on my roof generates around 1/3 more than I consume over the year. Everything is electric, I don't have natural gas. I have a heat pump for heating and cooling (rarely gets above 30c here). If I had a battery April - September could all be local consumption (I pull around 5kWh from the grid each day). The issue is winter: It gets down to -25c and there is very little sun (not that it would help due to snow on the panels). In January and February this year I generated a grand total of 5kWh :D However my house is a new house, it's designed to modern building standards and has 30cm of PIR insulation in the walls and even more in the roof. There's just no way to properly renovate old buildings to be like that without basically rebuilding the whole thing. The actual cost of materials is not expensive though (for the west). In milder climates (UK I'm looking at you) there's really no reason all new houses cannot be net-zero.

t0bia_s 20d ago
Modern building standard constantly changes. Time will show, how good they are. Meanwhile, we have, in Europe a lot of buildings from late 19, early 20th century that are perfectly habitable today and often are ruined by modern standards that not respect old standards. For example basement addition that prevents the apartments from “breathing” and causes them to become damp.