I'm looking to design an off-grid power system for my house. I'm a complete novice at this point but I'm willing to do a lot of reading to complete the project. There is a lot I still don't yet know and I have questions.
I want a system that will allow me to connect solar, wind, water and a gas generator. I'd like to have both the A/C and the D/C power sources go into the charge controller to charge my battery bank and then the battery bank connect to an inverter. This way, I have many types of input into my battery bank and failing everything else, I can power up the gas generator and that will charge my battery bank too.
I understand that the charge controller can push any excess electricity into a bypass.
- Am I seeking to do anything that is not possible with this?
- Is there a way for me to combine the A/C output from the inverter and the excess electricity from the charge controller as input to my house?
- If so, what is the device that would allow me to do this?
- Are there charge controllers that will receive both A/C and D/C input so that I can hook all my power sources into a single controller or do I need something more complicated to handle this scenario?
- Am I going about this the right way?
A little more background: As I commented in the notes, at the end of the year I am moving completely off-grid, so I have a year to figure out everything this entails and set it up - chickens, pigs, cows, water provisions, sewage and the whole 9 yards. I'm used to learning complex systems, so I know this is not beyond me. I've also lived an outdoor life for quite a lot of my life, so I'm used to being without the grid, so this won't come as a complete shock to me, but at the same time, I'm not looking to forego all modern conveniences. It's hard to throw out numbers as I'm not yet sure how exactly to calculate my needs.
Our hydro bill for last month has us pegged at averaging 29.84kW/h per day in January which thus far has been the coldest month of the year, December was 19.23kW/h per day.
Our heating/cooling and hot water are presently electric and the place we're presently living in has a criminal underuse of insulation between the units; this is not something I will suffer from with the next place. Not only will the insulation be better, but we're looking to move to geothermal to maintain a more temperate environment that will be supplemented by wood stove and propane for hot water, so I'm quite sure our energy requirements will drop significantly from our present requirements. We have high efficiency appliances, washer, dryer, fridge, freezer, dishwasher - I'd like to be able to continue using them - though I'm uncertain what the water situation will be yet, so the jury's still out on the feasibility/need for the dishwasher.
Our cooking stove is presently natural gas and I'll transition that to propane until I've mastered cooking on a wood burning stove.
I've put together a list of every piece of electrical kit we own, along with Wattage and Amperage requirements for each of them and put them into a spreadsheet, there's nothing particularly suprising on the list. I'm an avid cook/baker and I'd also like to be able to use all the tools in my workshop, most of which are presently electric, though I'm not averse to trading as many of those as I can to air drive.
I've been given advice that "peak" usage is what I should be gauging my electrical needs on - which means adding up all the appliances that will be in use concurrently, though a qualified(?) electrician we talked to suggested that that's not how you do it at all - can anyone advise if this is the case?
If I add up every electrical appliance we have, it totals 29kW & 234 amps. Near as I can tell, our peak load (max concurrent devices) would be around 15kW / 182 amps - and this assumes that washer, dryer, dishwasher, microwave, toaster, kettle, coffee machine and stand mixer, the tv, dvd player and sound system are all running, every light in the house is on and the fridge/freezer kick on - which rarely (if ever) happens. More typically, the washer, dryer and dishwasher don't get put on until after the kids are in bed, which means that most of the lights in the house are off and there's no cooking going on - though it's quite usual for the washer, dryer and dishwasher to all be running at the same time - whilst using TV (100W)/Sound (30W)/DVD (11W) and a couple of lights (perhaps 60-120W).