Need Design Advice! Building a brand new 2300sq ft 100% off grid

I’m new but I think you should consider a wind turbine or two to bolster that locations alt E 24 / 7. Amazing technology and simplicity

evotech said:

Looking for any advice I can get from those who have gone before me. Should I consider propane for stove, dryer, and heat to relieve some of the solar requirements? Any advice is appreciated.

Click to expand...

You won't have steep winter temp differences between inside and outside there in San Diego. If they still allow catalytic wood stoves there, it will be all that is needed. I live an hour north of Sac, (so cooler in the winter and hotter in the summer than S/D ) and I haven't lit my house furnace in over 20 years... nor have I had to buy a single stick of wood in all that time. I simply have gotten the word out that I am open to trim trees for our community in exchange for the wood. This has allowed me to maintain an average of four cords of hardwood here at all times.

Likewise, a simple batch solar water heater will provide all of the hot water that you would need.

I purchased two Rheem/Ruud Commercial 50 gal hot water heaters, both new on their pallets, from a gov't auction for $175 for the pair. These readily lent themselves to be used as passive hot water heaters. Housed in a well insulated enclosure, there is so much thermal banking of heat in 100 gallons, that 24/7 hot water is on tap.

I'm cipherin' a way to use the pool as an energy store.

I reccomend you go 100% electric
I did it in Florida 100% offgrid all electric home
Just finished it last year
I used icf for a total concrete shell
HPWH (heatpump water heater)
Geothermal heat pump
I built everything myself. (Extreme DIY)
My trade is solar

Here is my system

I have videos of my home build on my channel

Here is a cool battery backup system i did a few months ago

evotech said:

Great post. I am learning a lot reading it all. Thank you. Do you or anyone else have any opinions or experience with The Hot Point Heat Pump Water Heater/ AC Combo unit. It looks very interesting to me.

Click to expand...

I would personally avoid doing any business with Hot Spot Energy. I purchased a 48v heat pump from them and have had lots of trouble with it and their support was sub-par. I very much wish I had purchased a regular heat pump from one of the major brands instead of going super-efficient with this unit. As it is, I use it on occasion for cooling and never for heating because the machine errors out so frequently it's basically worthless for heating.

When diagnosing the heating errors, the company was slow to respond to support requests and eventually shipped me a new part, which didn't fix the problem. They promised to work with the factory in China that made the unit to find a resolution, but a year+ later, never have. I am very disappointed with their service and I actively steer people away from the company whenever possible.

evotech said:

Sorry that 30KWH was a daily average. So 900 KWH monthly. I have a gas stove and clothes dryer. I have plenty of time and motivation, so building my own battery system is definitly in the cards, unless that powerwall price is accurate. Being new construction, the tesla solar roof and powerwall almost actually makes sense with the hefty rebates. Doing a traditional roof will yield me no rebate on the roofing itself, just the solar, but going the tesla route I earn the rebate for the entire roofing of my new home. I know they are not designed for off grid, but it seems just a software update away or hopefully integrated into a V3 powerwall whenever that comes. I am probably 12 months out from roofing the house. I don't even have permits yet.

Click to expand...

That's what had me totally baffled,
I'm earth sheltered home, no real heating or cooling consumption, and according to the government about 20kWh is 'Average'.

I would design in any and all reasonable efficiency, starting with home insulation and sealing up everything against air leaks.

If the pool is mandatory, consider solar thermal for heating if needed.
Also consider salt opposed to chlorine so the pool doesn't need the extra circulation/cleaning/maintenance.

As much south facing roof as possible, for both thermal & PV panels.

Then research induction cook tops and steel/iron cookware.
While they are rated at really high consumption, the electro-magnetic induction is stupid efficient and you will burn everything past about half power.
The better a magnet sticks to the pan, the more efficient it will be with induction.
My 1,800 induction top will boil a gallon of water in under 3 minutes in cast iron.
It also doesn't heat the house up like gas or resistance electric that dumps a lot of heat into the room.

Think of it like a microwave for pots & pans.

Look at the consumption rate on everything, including timers or motion sensors for light switches, entertainment systems, etc. Nothing gets left on and wastes power.
I got light switches intend for outside with light sensors, you can't even turn a light on in common areas with big windows in the daytime without jumping though hoops.
Keeps that reflex of flipping on light when you don't need them under control.

That includes 'Smart Chargers' or timers on cell phone, pad, lap top chargers and any other 'Wall Wort' (transformer) chargers.
Those things are power hogs...

Consider sky lights or light pipes in common areas, the light pipe in my utility, bath, kitchen rooms do a great job, just the outside security light is enough to make light pipes effective night lights.

Conservation is ALWAYS the first step in Off Grid unless you are rich and stupid, and just insist on wasting energy.
Some idiots think wasting everything is a status symbol... I don't have much use for those types...

Once you have a good idea of consumption,
Then work at what feeds that consumption, an inverter properly sized.
Work back from there to panels that will SUPPLY every Watt or BTU.
Charge controllers that will pass that filtered power to consumption, and recharge batteries in a reasonable time.

Power, absent sunlight, will come from batteries or generator.
Batteries need to be sized for the normal loads needed,
If you don't want to do a generator, then a battery bank large enough to cover a day or two without sun,
Translation, a MUCH bigger battery bank, since it's not just nighttime power, but all power for a day or two.