My panels have two inclinations, summer and winter. Turns out, I leave them on winter year round. In the summer I have excess power (and can't sell it) regardless of the inclination. In the winter I need every photon.
Inside clothesline or rack? We have a small one we use in the winter. Only two of us though.
Actually on our island home we have hanging racks that we haul up to the ceiling. They are called Sheila Maids (one example
I am moving closer to this view all the time. But it's fair to say I still got a ways to go... we just got a 17kw Solar Roof installed, with 3x Powerwall 2. Don't have PTO yet, and already was starting to plan for another 3x Powerwall 2. Then I had a possible epiphany.... that $$ could just as likely pay for an expensive geothermal system. I've got a shortfall projected for annual production of about 7500 kwh. Our annual useage is about 22000kwh, incuding car charging. If I replace my water heater with a heat pump water heater, I'm projecting a 3000kwh reduction in that shortfall. If I go geothermal, that should take care of the rest of it, and then some. But of course the summer overproduction exceeds my storage capacity by many times over, and all of this is estimates - I haven't verified the first month's numbers.
You might be the sort who know about what a 2 ton ground source HVAC uses....? I sure would like to have some number to work with....
Have you done an energy audit yet ? That really should be the first step. You will likely find that low(er) cost insulation and improvement in leaks will be a smart move.Not only will you use less energy, you will be able to time shift
These days, for climates like Maryland, there isn't much difference in efficiency between an air source heat pump and a geothermal heat pump. When you factor in the difference in installation costs and maintenance, geothermal units rarely come out ahead anymore.
Interesting.... and a bit counter-intuitive, at least on the surface. Thanks for the suggestions - I'll look into that. The disruptive nature of putting in retrofit geothermal is what put me off that in the first place.
Basically, a geothermal pump generally has a higher Carnot efficiency because the difference in temperature between soil and the house temperature is generally small (54F vs 72F), but they require more energy to move the fluid through the piping, and heat exchangers. Air source heat pumps have a larger temperature difference (20F to 72F or 105F to 72F), but lower running energy losses. Twenty years ago, geothermal was a solid win. With today's air source heat pumps, not so much, and the cost to install the geothermal piping puts the ROI so far into the future that for many sites, it just doesn't pencil out.
With my mini splits, (4 compressors and 10 heads, half of these hardly even get turned on), and normal house, I use like 60 to 80kwh per day. And with a total day of rain, I might make only 5kwh.
Since I posted in early Feb, my wife and I have settled on a different path, we think. We won't achieve off grid capability, so I've come to accept a little fossil fuel into our equation.... started looking into a vent free propane fireplace. Something that could help with continuing thru a winter season extended power outage by reducing solar generation demand. A lot cheaper and less disruptive than revisiting geothermal.... we don't have a pond or ready available heat source, and the arrangement of our property and house make getting a well drilling rig in a feasible position close to the house is problematic at best. It's not so much ROI as near term feasibility, disruptiveness and cost. We don't realistically have sufficient runway left for real ROI considerations, and so are more motivated by energy security than ROI anyhow.
Your last statement about energy security over ROI is how we feel. We would love to have heat pumps, but with lots of shading we would only generate 8-9 kWh/day from November-January. And don't get over 25 kWh until late March. So, we use natural gas for heating and cooking.
