Ive just finished a starting installation of a battery and inverter solution at my place so I might be able to add some value in the discussion.
Ive got two young kids and the load shedding for our area was 6pm to 830pm which was pretty crap while trying to bath kids and put them to bed. My requirements were therefore:
- Fridge/freezer (I measured temps after 2 hours of no power. The freezer goes from -25 to 3. So I want to keep my fridge running during power outages)
- 4xTVs. One being a plasma that eats 450w
- my internet (3x routers)
- DSTV
- PCS: Interl NUC, Microserver, iMac, MAcbook Pro on charge and 3x RPis
- Various cellphone chargers
- All lighting (i already have LEDs) - I dont have more than 26 downlights on at the same time so that is only 130w
- outside lighting - also LEDs but at 50w.
In determining an inverter size you need to first determine what your max power usage will be. Dont assume that everything will on at once. For example - I dont have all 4 TVs on, but I would like to have them all on if need be. Also consider start-up power draw. The fridge is the largest for me - 500w. but after that it is anywhere between 5w and 100w. Its a AAA enegery grade samsung thing.
Go out and buy a power meter to measure if you arent sure, but you will be surprised how little power you use. Then work out an average.
Average light use: 150w
Fridge: 100w (startup 500w)
DSTV, RPis, and routers: 40w
imac: 40w
macbook: 50w
49inch LED TV: 80w
40 inch LCD TV: 80w
24 inch LCD: 50w
60 inch plasma: 450w
Based on my measurements I opted for a 1600w inverter with a surge rating of 2400w. Also with UPS function and auto changeover. It also charges the batteries. Dont cheap out on inverter or else you are stuck with it. Rather get less batteries and add on as you go - I started with 2x100Ah deep cycle 10 year life batteries.
at an average of 350w usage (with the plasma not being used which is often), these seemingly small battery pack runs it all for at least 5 hours.
In terms of wiring, the DB was split to exclude geyser, aircons, stove etc from the UPS, so it is connected to all plugs and lights. I cannot however use a kettle as mine draws 3000w and will overload the inverter and it would shut down. THis is why I have a changeover switch for so I manually switch to battery power, however when eskom power is restored I wouldnt know the difference due to teh auto changeover. You could choose to only include the plugs that can run off the inverter and leave it on permanently, but I dont have any life support systems or fish tanks that rely on power.
If I would like more up-time or want to use more power hungry items more often I can either triple the battery capacity or install solar to charge batteries during long outages.
Anyway, point is, it is pretty easy to start off small. Going off grid is another thing all together, and personally I dont think we are there yet. Although lets wait for winter...
Ive got two young kids and the load shedding for our area was 6pm to 830pm which was pretty crap while trying to bath kids and put them to bed. My requirements were therefore:
- Fridge/freezer (I measured temps after 2 hours of no power. The freezer goes from -25 to 3. So I want to keep my fridge running during power outages)
- 4xTVs. One being a plasma that eats 450w
- my internet (3x routers)
- DSTV
- PCS: Interl NUC, Microserver, iMac, MAcbook Pro on charge and 3x RPis
- Various cellphone chargers
- All lighting (i already have LEDs) - I dont have more than 26 downlights on at the same time so that is only 130w
- outside lighting - also LEDs but at 50w.
In determining an inverter size you need to first determine what your max power usage will be. Dont assume that everything will on at once. For example - I dont have all 4 TVs on, but I would like to have them all on if need be. Also consider start-up power draw. The fridge is the largest for me - 500w. but after that it is anywhere between 5w and 100w. Its a AAA enegery grade samsung thing.
Go out and buy a power meter to measure if you arent sure, but you will be surprised how little power you use. Then work out an average.
Average light use: 150w
Fridge: 100w (startup 500w)
DSTV, RPis, and routers: 40w
imac: 40w
macbook: 50w
49inch LED TV: 80w
40 inch LCD TV: 80w
24 inch LCD: 50w
60 inch plasma: 450w
Based on my measurements I opted for a 1600w inverter with a surge rating of 2400w. Also with UPS function and auto changeover. It also charges the batteries. Dont cheap out on inverter or else you are stuck with it. Rather get less batteries and add on as you go - I started with 2x100Ah deep cycle 10 year life batteries.
at an average of 350w usage (with the plasma not being used which is often), these seemingly small battery pack runs it all for at least 5 hours.
In terms of wiring, the DB was split to exclude geyser, aircons, stove etc from the UPS, so it is connected to all plugs and lights. I cannot however use a kettle as mine draws 3000w and will overload the inverter and it would shut down. THis is why I have a changeover switch for so I manually switch to battery power, however when eskom power is restored I wouldnt know the difference due to teh auto changeover. You could choose to only include the plugs that can run off the inverter and leave it on permanently, but I dont have any life support systems or fish tanks that rely on power.
If I would like more up-time or want to use more power hungry items more often I can either triple the battery capacity or install solar to charge batteries during long outages.
Anyway, point is, it is pretty easy to start off small. Going off grid is another thing all together, and personally I dont think we are there yet. Although lets wait for winter...
