Solar Air Conditioner
Okay for all boondockers needing to run air conditioning, gotta love ingenuity! :B Solar Air Conditioner
Forum Discussion
As Sushidog notes, going to higher voltages ameliorates a lot of problems
"...Wiring it at 48 volts, the amperage drops to 1/4 of what it would be for a 12v system. The wire size required drops too, making the wiring weight and expense 1/4 of what it would be for a similar wattage 12v system.." Son
Our son designed and fabricated our system so that the six 235 W panels are ganged in two series of 3 each so that they go to controller at around 90 V. The LFP batteries (each of 4 cells) are ganged in series to be a nominal 48 V (54.6V float) after going through controller etc. Having the panels in series requires that we try to find a "camping" spot that gives us solar for several hours each day.
Son has been in solar for 23 years after 6 years of research at New Mexico State University's Alternative Energy Labs. He just completed the contract for a 1.6 megawatt system for power company. He is off grid with 7 kW in mountains above Las Vegas, New Mexico; our daughter has 7 kW in Las Cruces; NM and brother-in-law has around 3kW in Albuquerque.
Our 1.42 kW solar and 9.6 kW-hour LFP combination is good for up to 4 hours with the 15,000BTU Dometic system (a power hog) with 50% DOD. We generally just run for an hour or so to get the temperature down to 85 and then let it recharge to -1000 kW-hours or so. As Almot noted regarding our earlier post, the 12V fan and Fantastic-fans make things quite livable with interior temperatures below 90 (provided the humidity is low.
We do have a Morningstar TS-MPPT-45 which is quite sufficient for 1300 W at 90 V. If we were to go to 2 kW solar, we might go to a TS-60 but the 45 should be sufficient at 90 V.
We have had the Lithium Iron Phosphate (LiFePO4) battery suite for 13 months now and have had zero problems. The suite is about 9.6 kW-hours and weighs 256 lbs. Prices have dropped quite a bit in the last year. One poster noted that a 14 kW-hr system was going for around $4.5k and a 24 kW-hr system was going for around $7k. Tesla may be selling 50 to 80 kW-hr suites (about 1000#)
Reed and Elaine
"...Wiring it at 48 volts, the amperage drops to 1/4 of what it would be for a 12v system. The wire size required drops too, making the wiring weight and expense 1/4 of what it would be for a similar wattage 12v system.." Son
Our son designed and fabricated our system so that the six 235 W panels are ganged in two series of 3 each so that they go to controller at around 90 V. The LFP batteries (each of 4 cells) are ganged in series to be a nominal 48 V (54.6V float) after going through controller etc. Having the panels in series requires that we try to find a "camping" spot that gives us solar for several hours each day.
Son has been in solar for 23 years after 6 years of research at New Mexico State University's Alternative Energy Labs. He just completed the contract for a 1.6 megawatt system for power company. He is off grid with 7 kW in mountains above Las Vegas, New Mexico; our daughter has 7 kW in Las Cruces; NM and brother-in-law has around 3kW in Albuquerque.
Our 1.42 kW solar and 9.6 kW-hour LFP combination is good for up to 4 hours with the 15,000BTU Dometic system (a power hog) with 50% DOD. We generally just run for an hour or so to get the temperature down to 85 and then let it recharge to -1000 kW-hours or so. As Almot noted regarding our earlier post, the 12V fan and Fantastic-fans make things quite livable with interior temperatures below 90 (provided the humidity is low.
We do have a Morningstar TS-MPPT-45 which is quite sufficient for 1300 W at 90 V. If we were to go to 2 kW solar, we might go to a TS-60 but the 45 should be sufficient at 90 V.
We have had the Lithium Iron Phosphate (LiFePO4) battery suite for 13 months now and have had zero problems. The suite is about 9.6 kW-hours and weighs 256 lbs. Prices have dropped quite a bit in the last year. One poster noted that a 14 kW-hr system was going for around $4.5k and a 24 kW-hr system was going for around $7k. Tesla may be selling 50 to 80 kW-hr suites (about 1000#)
Reed and Elaine
