My plan is radiant floors with an electric boiler, heat pumps in every room with an insanely tight building envelope… Plus, we save $25k out of the gate going without a natural gas connection.
The electric boiler is really attractive especially with the option of using A3 refrigerants. We bought an existing house which already had conventional HVAC ducting and very few A2L heat pumps were available this fall for purchase so we had to buy one of the last R-410a units.
, electric instahots at every sink/shower location,
I looked at that route but the energy efficiency is lower compared to other electric only options. Also the maintenance of descaling multiple times a year wasn’t appealing. We went with a tank-based heat pump water heater to replace the existing electric tank water heater. The energy efficiency has been amazing, and the side benefits of extra cooling and de-humidification in the basement where the unit is was nice.
and a massive solar array.
We put in a 17kW array with 10kWh of battery and its been wonderful so far. We haven’t had an electric bill since a month after installation, with this month being the first since then. If your state/locality has true 1:1 Net Metering, the cost of batteries isn’t worth it from a ROI perspective, but we were interested in not only that, but the backup capabilities in the even of an outage.
Good to know about the refrigerant, I haven’t even begun to consider different types of systems.
I didn’t think about the descaling, that’s definitely something to consider. My prime consideration with them was a) save on the extra piping, b) not have to wait for hot water to arrive, wasting water in the process (mountains, it gets a bit nippy up here), c) not have to operate a circ pump. I wouldn’t necessarily mind an electric tank WH, I just thought it’d be nifty having instant hot water in each room and not worrying about the tank running empty.
And yeah since we’re building from scratch, I intend on designing the roof with to accommodate as many panels as necessary (I haven’t even begun to do the load calcs for anything yet. In a perfect world, I’d want the front of the house facing north, leaving the entire south side of the house available for solar without cluttering up the curb appeal. Since we don’t have net metering where I’m at, I also have my eye on a battery system primarily for night operation and outages (they’re frequent up here), and as essentially a whole house UPS.
In a perfect world, I’d want the front of the house facing north, leaving the entire south side of the house available for solar without cluttering up the curb appeal.
This is a good strategy for producing the most electricity, but without net metering, it may not match when you need to use it. Southern facing will give you peak generation at noon. East facing will give you peak production in mid-morning. West facing will give you late afternoon-early evening peak. You can also have parts of your array in all of these directions, if your consumption is fairly even throughout the day.
For HOA reasons, I had to put all 44 panels on the back of my house which faces south-southwest. It was a happy accident that this is also nearly optimized for when we consume the most of our electricity. During the summer, the morning isn’t hot yet so we aren’t running AC much, by high noon we’re generating a really good amount already at the peak of the day heat. By late afternoon-early evening its still very hot and we’re starting to do our cooking and laundry which are larger consumers.
Since we don’t have net metering where I’m at, I also have my eye on a battery system primarily for night operation and outages (they’re frequent up here), and as essentially a whole house UPS.
If you don’t have net metering, make sure you don’t overbuild on your array and waste money. You’ll be producing more electricity than you can use during the daylight hours, and unless you’re buying a mountain of batteries (and batteries are expensive as-is) all that oversupply will go to waste. This is another place where a tank water heater would help you. With the Smart tank water heaters (heat pump or otherwise) you can set them for when they should heat, so you could set it to run while you have excess electricity, essentially a thermal battery.
Do you know if you have “Time of Use” (TOU) options for how you pay for your grid electricity? If so, you could reduce the amount of batteries you need and be able to shave off the most expensive hours (while you run on battery) knowing that your batteries will be close to exhausted most nights, but you’ll recharge them on morning sun.
Our utility up here is pretty much a “you’re lucky we even offer you power” type, so yeah they have nothing for as far as rate incentives or the like. At this point the idea is to operate as if we are off grid, as to only pay the utility access fee (or completely disconnect if possible, I know there are certain legalities with that I need to look into as California tends to frown upon off grid living when utilities are available). Same reason I want a well and have a city water connection as backup. Sewer, trash collection, and Internet would be from local providers.
My current train of thought is, depending on the inverter and charge controller, is to draw direct from solar during the day and batteries at night. Again I haven’t done load calcs, but system sizing depends on max average load during the day while simultaneously charging the batteries. Again a lot of this depends on the house orientation on the lot we get, and how I can balance the design of the house with technical requirements.
I haven’t even gotten into which batteries I’d go for, but I’m leaning towards off the shelf 12/24vdc industrial batteries that I can easily swap as opposed to a monolithic prepackaged system from a company that I may not be able to service myself. My goal is to remain manufacturer agnostic so I don’t run into servicing issues.
The electric boiler is really attractive especially with the option of using A3 refrigerants. We bought an existing house which already had conventional HVAC ducting and very few A2L heat pumps were available this fall for purchase so we had to buy one of the last R-410a units.
I looked at that route but the energy efficiency is lower compared to other electric only options. Also the maintenance of descaling multiple times a year wasn’t appealing. We went with a tank-based heat pump water heater to replace the existing electric tank water heater. The energy efficiency has been amazing, and the side benefits of extra cooling and de-humidification in the basement where the unit is was nice.
We put in a 17kW array with 10kWh of battery and its been wonderful so far. We haven’t had an electric bill since a month after installation, with this month being the first since then. If your state/locality has true 1:1 Net Metering, the cost of batteries isn’t worth it from a ROI perspective, but we were interested in not only that, but the backup capabilities in the even of an outage.
Good to know about the refrigerant, I haven’t even begun to consider different types of systems.
I didn’t think about the descaling, that’s definitely something to consider. My prime consideration with them was a) save on the extra piping, b) not have to wait for hot water to arrive, wasting water in the process (mountains, it gets a bit nippy up here), c) not have to operate a circ pump. I wouldn’t necessarily mind an electric tank WH, I just thought it’d be nifty having instant hot water in each room and not worrying about the tank running empty.
And yeah since we’re building from scratch, I intend on designing the roof with to accommodate as many panels as necessary (I haven’t even begun to do the load calcs for anything yet. In a perfect world, I’d want the front of the house facing north, leaving the entire south side of the house available for solar without cluttering up the curb appeal. Since we don’t have net metering where I’m at, I also have my eye on a battery system primarily for night operation and outages (they’re frequent up here), and as essentially a whole house UPS.
This is a good strategy for producing the most electricity, but without net metering, it may not match when you need to use it. Southern facing will give you peak generation at noon. East facing will give you peak production in mid-morning. West facing will give you late afternoon-early evening peak. You can also have parts of your array in all of these directions, if your consumption is fairly even throughout the day.
For HOA reasons, I had to put all 44 panels on the back of my house which faces south-southwest. It was a happy accident that this is also nearly optimized for when we consume the most of our electricity. During the summer, the morning isn’t hot yet so we aren’t running AC much, by high noon we’re generating a really good amount already at the peak of the day heat. By late afternoon-early evening its still very hot and we’re starting to do our cooking and laundry which are larger consumers.
If you don’t have net metering, make sure you don’t overbuild on your array and waste money. You’ll be producing more electricity than you can use during the daylight hours, and unless you’re buying a mountain of batteries (and batteries are expensive as-is) all that oversupply will go to waste. This is another place where a tank water heater would help you. With the Smart tank water heaters (heat pump or otherwise) you can set them for when they should heat, so you could set it to run while you have excess electricity, essentially a thermal battery.
Do you know if you have “Time of Use” (TOU) options for how you pay for your grid electricity? If so, you could reduce the amount of batteries you need and be able to shave off the most expensive hours (while you run on battery) knowing that your batteries will be close to exhausted most nights, but you’ll recharge them on morning sun.
Our utility up here is pretty much a “you’re lucky we even offer you power” type, so yeah they have nothing for as far as rate incentives or the like. At this point the idea is to operate as if we are off grid, as to only pay the utility access fee (or completely disconnect if possible, I know there are certain legalities with that I need to look into as California tends to frown upon off grid living when utilities are available). Same reason I want a well and have a city water connection as backup. Sewer, trash collection, and Internet would be from local providers.
My current train of thought is, depending on the inverter and charge controller, is to draw direct from solar during the day and batteries at night. Again I haven’t done load calcs, but system sizing depends on max average load during the day while simultaneously charging the batteries. Again a lot of this depends on the house orientation on the lot we get, and how I can balance the design of the house with technical requirements.
I haven’t even gotten into which batteries I’d go for, but I’m leaning towards off the shelf 12/24vdc industrial batteries that I can easily swap as opposed to a monolithic prepackaged system from a company that I may not be able to service myself. My goal is to remain manufacturer agnostic so I don’t run into servicing issues.