3 ms·

What Faak said. I’m living on off grid solar and my tech (TV, Xbox, NAS, LED lights etc) never misses a beat, even when a big load turns on. It’s the old tech (

What Faak said. I’m living on off grid solar and my tech (TV, Xbox, NAS, LED lights etc) never misses a beat, even when a big load turns on. It’s the old tech (i.e. motors) that are actually a bit more fussy.

csours 7y ago
What about running out of power?
- adamcharnock 7y ago
  Well at that point everything turns off :-) I’m still running the system in, so the (NiFe) batteries are not at full capacity yet (perhaps only at 30%-50% storage capacity). Even so I can easily stay up until 2am watching TV. And that’s only with 4 (25%) of the panels out (it is summer though, I’ve yet to do a winter.). Oh, and I’m running a fridge/freezer on that too. Still, probably going to get a UPS for the NAS soon. Edit: just to rabbit on a bit more - panels are cheap. They only accounted for around 20-25% of the total system cost. Power storage is the expensive part (more like 40% of the cost). It is interesting to try to tailor my systems to draw power at suitable times of day. At 2pm I have more power than I know what to do with, I could happily run 3kw load for a few hours most days around that time. At the batteries theoretical max capacity I have 10kWh stored, but I’m only getting around 3kWh at the moment. I’ve got a backup generator to cover any extreme weeks in winter. Figuring out the water pumping/irrigation has been a fun one I’ve been looking at today. The trees will have wood chip moats around them, a side effect of which is they can be watered at any time of day (which is great), but watering the grass must happen when it isn’t sunny (so maybe I can squeeze in a watering when the last rays are hitting the panels, or first thing in the morning). As a software developer it’s an absolute dream.
  - dev_dull 7y ago
    extremely cool! How easy was it to disconnect from the grid? What's your city/county? Also, just curious, why did you decide on NiFe? Most off-grid folks I know either use li-ion for density or lead acid for cost/abundance/ease-of-use. > At 2pm I have more power than I know what to do with, I could happily run 3kw load for a few hours most days around that time. A fun and interesting problem to have. This is why we need so much more research into energy storage.
    - adamcharnock 7y ago
      I've moved to rural Portugal (from London). I would have to get the grid extended to my place in order to get grid power, and I was quoted at around €30k. I realised that for a fraction of the price I could get a pretty beefy solar system (and – you know – free power thereafter). I went for NiFe batteries because they they are basically impossible to break. This is my first system, and I wanted to take the reliable and stress-free path. Space wasn't a concern. NiFi batteries also last circa 40 years, so the price per year is actually very cheap. However, my planning horizon is definitely not that long.
  - benj111 7y ago
    Pumped hydro. Pump the water into header tanks, then it doesn't need electricity to water the grass, and you could generate electricity too. Or... Just don't water the grass?
    - llukas 7y ago
      I wonder how viable is to cool down some thermal mass? (similar to HVAC systems taking advantage of cheap electricity at night). Fridge can be "pre-cooled" and cut power usage at night.
      - icebraining 7y ago
        Joey Hess (the git-annex developer, also lives off-grid) has done a lot of experimentation with his fridge, including adding a thermal mass: https://fridge0.branchable.com/thermal_mass/ https://fridge0.branchable.com/thermal_mass/
        adamcharnock 7y ago
        That is very interesting to me, thank you!
      - ElKrist 7y ago
        In winter I turn up the max temperature of my water heater. This way I can soak more energy into it when it's "off-peak" (cheaper) hours for electricity. You just have to be careful not opening the tap on the hottest temperatures anymore. I don't see how you picture it with the fridge though. Aren't you limited by the fact that you can't go down much below 0°C ? Or perhaps you add some new mass? Where do you actually put this mass when the fridge is already full?
        llukas 7y ago
        Right with fridge there is not much wiggle room - but each fridge contains freezer compartment?
    - 7y ago
  - deleted 7y ago
    [deleted]

csours 7y ago

What about running out of power?

adamcharnock 7y ago
Well at that point everything turns off :-) I’m still running the system in, so the (NiFe) batteries are not at full capacity yet (perhaps only at 30%-50% storage capacity). Even so I can easily stay up until 2am watching TV. And that’s only with 4 (25%) of the panels out (it is summer though, I’ve yet to do a winter.). Oh, and I’m running a fridge/freezer on that too. Still, probably going to get a UPS for the NAS soon. Edit: just to rabbit on a bit more - panels are cheap. They only accounted for around 20-25% of the total system cost. Power storage is the expensive part (more like 40% of the cost). It is interesting to try to tailor my systems to draw power at suitable times of day. At 2pm I have more power than I know what to do with, I could happily run 3kw load for a few hours most days around that time. At the batteries theoretical max capacity I have 10kWh stored, but I’m only getting around 3kWh at the moment. I’ve got a backup generator to cover any extreme weeks in winter. Figuring out the water pumping/irrigation has been a fun one I’ve been looking at today. The trees will have wood chip moats around them, a side effect of which is they can be watered at any time of day (which is great), but watering the grass must happen when it isn’t sunny (so maybe I can squeeze in a watering when the last rays are hitting the panels, or first thing in the morning). As a software developer it’s an absolute dream.
- dev_dull 7y ago
  extremely cool! How easy was it to disconnect from the grid? What's your city/county? Also, just curious, why did you decide on NiFe? Most off-grid folks I know either use li-ion for density or lead acid for cost/abundance/ease-of-use. > At 2pm I have more power than I know what to do with, I could happily run 3kw load for a few hours most days around that time. A fun and interesting problem to have. This is why we need so much more research into energy storage.
  - adamcharnock 7y ago
    I've moved to rural Portugal (from London). I would have to get the grid extended to my place in order to get grid power, and I was quoted at around €30k. I realised that for a fraction of the price I could get a pretty beefy solar system (and – you know – free power thereafter). I went for NiFe batteries because they they are basically impossible to break. This is my first system, and I wanted to take the reliable and stress-free path. Space wasn't a concern. NiFi batteries also last circa 40 years, so the price per year is actually very cheap. However, my planning horizon is definitely not that long.
- benj111 7y ago
  Pumped hydro. Pump the water into header tanks, then it doesn't need electricity to water the grass, and you could generate electricity too. Or... Just don't water the grass?
  - llukas 7y ago
    I wonder how viable is to cool down some thermal mass? (similar to HVAC systems taking advantage of cheap electricity at night). Fridge can be "pre-cooled" and cut power usage at night.
    - icebraining 7y ago
      Joey Hess (the git-annex developer, also lives off-grid) has done a lot of experimentation with his fridge, including adding a thermal mass: https://fridge0.branchable.com/thermal_mass/ https://fridge0.branchable.com/thermal_mass/
      - adamcharnock 7y ago
        That is very interesting to me, thank you!
    - ElKrist 7y ago
      In winter I turn up the max temperature of my water heater. This way I can soak more energy into it when it's "off-peak" (cheaper) hours for electricity. You just have to be careful not opening the tap on the hottest temperatures anymore. I don't see how you picture it with the fridge though. Aren't you limited by the fact that you can't go down much below 0°C ? Or perhaps you add some new mass? Where do you actually put this mass when the fridge is already full?
      - llukas 7y ago
        Right with fridge there is not much wiggle room - but each fridge contains freezer compartment?
  - 7y ago
- deleted 7y ago
  [deleted]