I compared our mid-April to mid-May NV Energy bills for 2019, 2020 and 2021 to get an idea of how our new hot water heater affected our energy use. The good news is that we used 59% less natural gas! We used an average of 34 therms in 2019 and 2020, and only 14 in 2021! So, it made a huge difference in our natural gas use.

Our use of electricity was up about 130 kWh from this time last year. The new hot water heater likely made up about 80 kWh of the increase. The other 50 kWh was likely due to a colder May this year and increased travel in our LEAF. It was about 9 degrees colder in May, 2021 than in May, 2020, so we used more of our booster electric heaters this year. Our parents are needing more help these days, so we are traveling more in the LEAF to assist them.

We are loving this new hot water heater! We’ve pretty much left it on the Heat Pump Only setting, which is the most efficient. This gives us the same hot water we are used to having with our old system. It works fine for the two of us, as long as we don’t take back-to-back showers, which we don’t usually do. If we have a higher use day, or have guests, we can set it to Hybrid or Electric mode. If we set it in Electric mode, it will automatically revert to Heat Pump Only in 12 hours.

An extra added bonus as we get into the warmer months is it keeps the garage cooler, because it takes the warm air from the garage to heat the water, expelling cold air out of the tank. It does make a bit of noise when it is in operation, so I can see that you may not want it inside your house. It works great in the garage. So far we haven’t noticed any condensation coming out of the unit in our dry climate.

Our next adventure will be adding a heat pump heater and A/C unit, so stay tuned!

Isn’t she a beauty? What? You don’t think water heaters are sexy? Oh, but she is hot and super-efficient! I bet you’re wondering what is a “hybrid heat pump water heater”?

NOTE: This post has been updated as of May, 2025. Changes are in red.

A hybrid water heater, or heat pump water heater, uses heat from outside air drawn into the appliance’s evaporator coil. The evaporator coil contains refrigerant, allowing it to absorb heat from the air. Finally, a heat exchanger heats water within the tank to the desired temperature before it passes from the heater tank into your home’s showers, faucets, and large appliances.

This electric water heater uses heat from outside air drawn into the appliance’s evaporator coil. The evaporator coil contains refrigerant, allowing it to absorb heat from the air. Finally, a heat exchanger heats water within the tank to the desired temperature before it passes from the heater tank into your home’s showers, faucets, and large appliances. It’s helpful to think about this process as being like that of your refrigerator, but in reverse. Instead of expelling hot air to cool the contents of a refrigerator or freezer, a heat pump water heater pulls hot air in to heat the water. Because it moves heat, it is over 50% more efficient than a standard electric water heater.

Our water heater is a Bradford White Model #RE2H50S10. It has three settings: heat pump only, hybrid, and electric. The most efficient setting is the heat pump only, which works when the ambient temperature is higher and hot water demand is lower. The hybrid mode will use the heat pump and when it can’t find enough heat to move, it will create heat through heating elements (like a standard electric water heater). That is why it is called a hybrid. The electric mode is useful if you have a lot of people taking showers at one time. This mode uses the heating elements to keep up with the demand. Afterwards, you can reset it to hybrid or heat pump only, or it will default back to hybrid within 12 hours if you forget to reset it. It is expected to use 958 kWh per year of electricity. In our colder climate, we estimate we use about 1500 kWh to power this unit.

Did you know that your water heater is one of the most energy intensive systems in your home? According to the EPA, “If every residential electric water heater in the country were replaced with a heat-pump water heater, 140 billion pounds of annual greenhouse gas emissions would be prevented, equivalent to the emissions from more than 13 million vehicles.” Here’s a good article on the subject if you want to learn more: https://www.thisoldhouse.com/plumbing/21015567/all-about-heat-pump-water-heaters.

We chose this water heater so we could use more of our solar power and less natural gas to heat our water. This meant replacing our old natural gas system with an electric one. We were waiting until our 20-year-old gas water blew up, which it did over the winter. Fortunately, Scott had a backup on hand to get us through until our hybrid could be produced and shipped to us (took about a month due to Covid, but you can get one from another manufacturer at Home Depot or Lowes immediately). Thankfully, Scott was able to install the 220-volt circuit himself and our friend, Brad helped with the installation of the tank. So, our labor costs are less than normal for making this switch.

Here are the costs:

• $1,428 Bradford White Model #RE2H50S10
• +$600 Labor for Installation
• =$2,028 Total
• -$700 Less Cost to replace with a new gas water heater
• -$300 Less Federal Tax Rebate
• =$1,028 Additional cost of switching to a hybrid electric water heater

We will add this to our solar installation costs and see how long it takes us to recover our investment. However, our main reason for choosing this system is to reduce our carbon footprint by burning less natural gas to heat our water.

Our heat pump water heater has been saving us about 235 therms of gas per year. Our average gas cost is about $0.50 per therm. So we save about $118 per year. That means the system will pay for itself in about 8.5 years. We hope it will last 20 years like the last one did-then we come out way ahead!

You might be wondering what a heat pump water heater can save your household. For a family of four, the Energy Star website estimates you would save around $330 a year on your electric bill, which adds up to a savings of around $3,400 over the life of a typical heat pump water heater. This is assuming you had an electric hot water heater to begin with-we had gas. An average new electric hot water heater costs between $300 and $600. If you already have an electric hot water heater, the additional cost (less the federal tax rebate) is only $500-$800 more. This would be paid for by your savings within 1.5-3 years. Plus, it’s so much better for the environment! (Ours was more expensive because we had to switch from gas to electric.)

Additional Information About Our Hot Water System

We are lucky to have a circulation pump system in our home, which helps us use less water. This system gives us instant hot water, so we don’t have to run a lot of cold water through the pipes, waiting for it to get hot. In our desert climate, where water is so precious, it is nice to have. Depending on your home’s construction, it can be added, but it is easier to do during new home construction. If you are building a new home, this is something worth considering.

Here’s Scott’s explanation and diagrams on how this works:

This is our house if we had a traditional hot water system. The hot water heater (HWH) is in the garage and there would be plumbing that extends, one way, from the HWH to wherever hot water is needed.  In our case, the master bathroom and the kitchen. (For simplicity forget that we have a laundry room and a guest bathroom.) If we turn the hot water on in either of these locations after not using it for an hour or two, the water coming out is cold, so we have to run the hot water for a minute or two before it becomes warm then hot.

This is how our house was built. There is an extra hot water line (in yellow) that runs from the Master to the Kitchen. This creates a hot water loop. There is a hot water circulation pump next to the HWH (red device in this “Circulation Pump” picture):

It continuously circulates the hot water through the loop and then through the HWH. Anytime we turn the hot water on in the Master or Kitchen, the hot water is piping hot. We do not have to wait. This system is good in deserts like Nevada where water is not abundant. We do not want people to let precious water run down the drain waiting for it to get hot.

Scott has the timer set so the pump is off at night when we are not using hot water.

Bottom Line After Four Years of Use

We love this heat pump! It is our favorite heat pump system and has reduced our use of natural gas the most and saved us the most money. It works as well as our old system did to heat our water, and an extra benefit is it cools off our garage in the summer by taking the hot air and putting it into the water. Very cool!

NOTE: This system does make some noise, so it is probably not a great system to have in the house where you can hear it. It works great in the garage.

Our Online SolarEdge Panel. Click to see what we are producing with our rooftop solar array!

Reflections on our Second Year of Going Solar & Driving the Cars of the Future

I won’t repeat here all I said in my first annual report, so if you want to read that one, click this link: https://rhondaashurst.com/2020/02/03/1st-annual-solar-report-for-2019/. This post gives information on our initial set up and the purchase of our EV and Hybrid vehicles.

IT JUST KEEPS GETTING BETTER! We continue to enjoy the thrill of driving the cars of the future, greatly decreasing our carbon footprint, using the sun to power more of our home and transportation, and watching the savings pile up. Of all our home improvements, going solar has been our best decision.

Our gratitude to Travis and the guys at Great Basin Solar (https://www.greatbasinsolar.com/) for the awesome job they did designing and installing our system!

Here’s the summary for this year with cumulative data:

We produced about 13 megawatts of electricity in 2020, about 1 megawatt more than originally estimated. We saved almost $3,000 between our utility bills and the lower costs of driving electric and hybrid vehicles. At this rate, we will recover our costs in 2.5 more years. We also saved over 22,000 pounds of CO2 from entering our atmosphere, and a total of nearly 45,000 pounds over the 2 years since we installed the system!

This year I added in our CO2 savings from burning less natural gas in our home, due to using electric zone heaters during the winter. Next year we plan to replace our aging water heater and air conditioning unit with super-efficient electric heat pump models. The A/C unit will include a heater that extracts heat from the air to warm our home in the cooler months, reducing even further our use of the gas furnace. It will be fun to see how much more gas we will save in the coming years by making those two simple changes that we need to make anyway.

It is definitely driving the cars of the future that saves the most. For a fun read on what you can save by driving electric or hybrid vs. gas-powered vehicles, check this out: Article on cost and climate savings of Electric and Hybrid Vehicles. It includes information from MIT on a variety of different cars–the cost of driving them and their carbon emissions.

THE DATA

Electricity Production and Accumulated Credits

Our panels produced 12.9 megawatts, almost 1 megawatt over what Travis estimated when he built our system. We only slightly increased our banked electricity with NV Energy to 2.66 megawatts from 2.60, so we used almost all the electricity we generated this year. The difference was caused by (1) using electric zone heaters in the winter to reduce our gas usage, (2) plugging in a second refrigerator for most of the year due to stocking up to weather the pandemic and keep our parents supplied with groceries, and (3) running more A/C at night in the summer.

Averaging our 2017 and 2018 utility bills, we paid $1269 annually for electricity and gas. This year we paid only $614 for a savings of $654! We decided to look at our total utility bill, since we are now using electric heaters to lower our use of natural gas to heat our home in the winter. Next year we expect to use even less gas when we install the new heat pump systems.

The Natural Gas Log is a record of our gas usage in therms. It went down 18% in 2020 for a savings of 110 therms and 1320 pounds of CO2. We are excited to see how much it will change when the new systems are installed!

Above are the SolarEdge graphs showing our total production in 2020 and the comparison of 2019 and 2020. Our system didn’t go online until February 19, 2019. You can see that our lowest production months are November-January, which is when we are using the electric zone heaters and running Christmas lights. It’s during these months that we tap into our banked power with NV Energy. In the higher production months, we send more power into the grid, which is used by other households and increases our banked power.

This is our December NV Energy bill showing our banked credit of $212.71 (line right above Meter Information). Divided by the 8 cents per kWh charge, the bank equals 2.66 megawatts of stored power. We used less electricity this December than last December, because we switched from incandescent to LED Christmas lights for the exterior of our house. We couldn’t believe it when we learned that 1 incandescent bulb uses the equivalent of 2 STRINGS of LED lights! OUCH! So, we ought to use a lot less electricity for the 6 weeks of Christmas lights.

The changes we made this year saved natural gas and used more of our solar power. Once the new systems are installed in 2021, we may start tapping into our bank. We’ve decided to monitor our electric use for a year and if we need to, we will install more solar panels.

2016 Nissan LEAF

We are still loving driving our LEAF! We used BeeBee even more than the Highlander this year, since we didn’t travel long distances as much due to the pandemic. However, the total miles driven (6084) was about the same as last year. We used 1.5 megawatts of electricity to power her. If we didn’t have solar panels, it would’ve only cost us $123! That is a savings of around $713 over my old Subaru! (So, it pays to have an EV whether you have solar or not.) But, because we have solar panels, our savings is actually $836! Plus we saved 5800 pounds of carbon dioxide from entering the atmosphere (290 gallons X 20 lbs/gallon of gas).

We also saved money on repairs and maintenance. I have driven 100,000+ ICE vehicles for most of my life and they have high R&M bills, about $900 per year on average. This year the LEAF had her 30,000 mile check up, which is a big one, but it only cost $410. So the LEAF cost $490 less to maintain than my old vehicles. This brings the total savings of driving the LEAF for a year to $1,323! (NOTE: This will decrease as the car ages and the R&M bills get higher.) In future years, I will keep a running total of savings so you can see how owning an EV plays out over time. Most EV’s cost about 1/3 of an ICE to maintain due to not having engines and transmissions, and saving the brakes with regenerative braking.

We did lose one bar on the battery indicator this year, meaning that the battery pack is beginning to degrade. This is a normal occurrence and actually I’m surprised we haven’t lost more than one bar given that the car is now 4 years old. We have not noticed any change in our range, so that’s the most important thing. Nissan says to expect 10 years of battery life or 100,000 miles. Our LEAF has only about 34,000, so we should be good to go for long time!

The best part for us has been the pure joy of driving this car and knowing we are powering it with Nevada sunshine and emitting zero carbon and no pollution. We use it most of the time, saving the Highlander for when we need two cars or will be traveling out of the LEAF’s 100-mile range, which wasn’t much this year as you’ll see below.

2019 Toyota Highlander Hybrid

We also still love our Highlander–what a luxurious and smooth ride with lots of fun bells and whistles! We drove 4526 miles during 2020, significantly less than 2019, because we didn’t do long trips and used the LEAF more around Reno. We used only 159 gallons of gas, a savings of 124 gallons and $356 over the 4-Runner for the same mileage, and 3180 pounds of carbon emissions (159 gallons X 20 lbs/gallon). This savings does not take into account the fact that we drove less this year because of the pandemic. So, technically there was even more savings than the formulas above show. I think that was true for most of us. I loved all the data coming out this year that showed how much better our air quality was and how much less carbon we produced worldwide. It gave me hope that we can change our habits and have a healthier planet, which in turn makes us (and everything else living on Earth) healthier too.

The Highlander was still on its 2-year free maintenance contract with Dolan Toyota, so we saved the $590 average, inflation-adjusted cost we used to spend maintaining the 4-Runner. This brings the total savings of driving the Highlander to $947! Hybrids cost about 2/3 as much to maintain as regular ICE vehicles, due to the use electric motors and regenerative braking. We will see how this averages out over time.

This is our all-around vehicle and it continues to do everything we need it to. It is way more comfortable and pleasurable to drive than our old 4-Runner. The combo of the Highlander and the LEAF is perfect for us. We saved $2,273 and nearly 9,000 pounds of carbon from entering our atmosphere. We are thrilled with our decision to replace our old internal combustion engine (ICE) vehicles with the cars of the future!

Stay tuned for updates when we add in our hybrid heat pump systems this year!