I have a home in Hawaii, where net metering was ended in 10/2015. I have 60x330w = 19.8 kWdc connected to 2 Solaredge HD Wave inverters (10k, 7.6k). Six months per yr I live there and use 2 EVs. Six months/yr it is a vacation home on the Sunniest but hottest part of the island where renters run my AC 24/7 as low as I will permit them (72F). During both periods my production is usually close to but some times 10-20 kWh below my consumption. However, I usually export & import about 35-50 kWh during the 6 months that guests use it due to high AC use. My utility credits me $0.1 & I pay $0.32kWh for export/import amounting to $350-450/month when guests are present. My AC comes from an Icebear 20, which I have programed to make 'ice' from 9a-5p. The IB20 uses the 'ice' to chill the coolant after 5 pm til it isn't cool enough to help. When I am there, it can keep my master BR ~76F til 2-3 am. When renters are there, the 20 tons of cooling from the ice last 2-3 hr.
I self consume as much power as I can by running my pool pump & heater, making 'ice, super heating my HPHW tanks to 140F and charging my EVs from 8:30a-4:30p.
One solution is to add batteries but they are very expensive on the Big Island. There is no Tesla Direct solar here and local installers charge about $12-14k per PW2. I would prefer LG Chem 16 kWh (~$8k each) batteries because they can be connected DC-DC, which not only provides slight increased efficiency but would allow me to oversize my inverters without clipping. My HD Wave inverters can not be linked DC-DC to batteries. I could replace my 7.6 kW inverter with a 7.6 energy hub inverter & connect that to two 16 kWh LG Chem batteries. A new inverter plus the back up unit would be about $5k. I can use the original 7.6 inverter at my other house.
Another step might be to change my AC system to decrease my AC power consumption. The IB20 has a SEER of 14 but newer AC units have SEERs of 22 or higher. I could add a higher efficiency AC unit and switch the IB20 to just making ice from 8:30a-4:30p and using the 'ice' after 5 pm. Does anyone know how much less power a 22 SEER AC would consume vs the 14 SEER? That would probably cost less than $10k.
Any thoughts or suggestions?
20210911_035308.jpgimage_14755.jpg 20210911_035308.jpg
I self consume as much power as I can by running my pool pump & heater, making 'ice, super heating my HPHW tanks to 140F and charging my EVs from 8:30a-4:30p.
One solution is to add batteries but they are very expensive on the Big Island. There is no Tesla Direct solar here and local installers charge about $12-14k per PW2. I would prefer LG Chem 16 kWh (~$8k each) batteries because they can be connected DC-DC, which not only provides slight increased efficiency but would allow me to oversize my inverters without clipping. My HD Wave inverters can not be linked DC-DC to batteries. I could replace my 7.6 kW inverter with a 7.6 energy hub inverter & connect that to two 16 kWh LG Chem batteries. A new inverter plus the back up unit would be about $5k. I can use the original 7.6 inverter at my other house.
Another step might be to change my AC system to decrease my AC power consumption. The IB20 has a SEER of 14 but newer AC units have SEERs of 22 or higher. I could add a higher efficiency AC unit and switch the IB20 to just making ice from 8:30a-4:30p and using the 'ice' after 5 pm. Does anyone know how much less power a 22 SEER AC would consume vs the 14 SEER? That would probably cost less than $10k.
Any thoughts or suggestions?
20210911_035308.jpgimage_14755.jpg 20210911_035308.jpg
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