A number of years in the past I began writing commonly about electric cars and the batteries that energy them—applied sciences which can be serving to humanity transition away from reliance on fossil fuels. And as dangerous information continued to pile up concerning the harms attributable to local weather change, I began to suppose tougher about my own carbon footprint.
So final yr, my spouse and I bought solar panels for our roof. Then we changed our air conditioner, getting a mannequin with a warmth pump functionality. Shortly after that, our boiler sprang a leak and we bought a brand new high-efficiency boiler. Then we bought a battery electrical automotive.
We’ve not but achieved a carbon-free way of life. The brand new boiler burns pure gasoline and we’re conserving our previous gasoline-powered automotive. We even have an oven and fireside that run on pure gasoline. Nonetheless, our carbon emissions in 2021 might be far decrease than they had been in 2019. And we’re on a path to radically cut back our carbon emissions over the subsequent decade.
Authorities insurance policies had been a giant assist right here. The federal authorities gives beneficiant incentives for the acquisition of photo voltaic panels and electrical autos. The District of Columbia, the place we reside, gives further incentives for each. Not solely did these immediately cut back our out-of-pocket prices, they’ve additionally helped producers achieve economies of scale that made these applied sciences inexpensive within the first place.
So I believed strolling by the expertise may inform—and maybe encourage—others who could be contemplating taking an analogous leap.
Rooftop photo voltaic
My inexperienced power odyssey began with photo voltaic panels. My spouse and I reside in a Washington DC row home with a gently-sloping, south-facing roof. With no tall timber behind the home, it is excellent for producing energy all day lengthy.
Within the spring of 2019, I bought quotes from two photo voltaic corporations. One firm wished $35,538 for a 8.5 kW system with 26 panels. The opposite agency quoted us $33,372 for a 8.64 kW system with 24 panels. In both case, we would get a 30 % federal tax credit score price greater than $10,000, bringing the web value under $25,000.
We determined to go along with the costlier vendor. The cheaper bidder wished to anchor the photo voltaic panels on to the roof, whereas the costlier proposal would droop the panels from beams mounted on the parapet partitions on both facet. The primary agency assured me that they may seal the roof up good as new, however the concept of chopping into the roof made me nervous.
Later, the successful contractor informed us that our roof was nearing the tip of its life and would value extra to exchange after photo voltaic panels had been put in. So we determined to have them change our roof. Our chimney was additionally in dangerous form, so we had a special firm rebuild that. This added $17,482 to the price of the undertaking. We financed all of this—and the HVAC upgrades I am going to focus on shortly—with a house fairness mortgage.
The roof was put in in early August. The photo voltaic panels arrived in October. Then there was a month’s await Pepco to hook up the system to the electrical grid. Our system was lastly lively in November 2019.
Photo voltaic panels solely generate energy within the daytime. So if we wished to construct a self-contained system, we might have wanted to purchase batteries to retailer extra energy within the day and to be used at evening. However fortunately for us, DC regulation requires our electrical utility, Pepco, to do what’s often called internet metering. When we’ve got extra energy, Pepco credit us at retail charges, successfully offering us with free power storage.
Our photo voltaic panels pays for themselves in 5 years
In 13 months of operation, our system has generated greater than 11 MWh of energy, which our photo voltaic system’s web site estimates saved us $1,250. Our electrical payments replicate that. Within the yr earlier than the photo voltaic panels had been put in, our electrical payments totaled $1,254. Over the next yr, we paid solely $72.
Nonetheless it will have taken greater than 20 years for the photo voltaic panels to pay for themselves based mostly solely on these electrical energy financial savings. Fortunately, free electrical energy wasn’t the first profit for us.
Beneath DC regulation, Pepco should purchase a rising share of its electrical energy from renewable sources. Pepco can both generate renewable energy itself or purchase photo voltaic renewable power credit (SRECs) from third events like us.
Due to DC’s stringent inexperienced power necessities, SRECs within the district promote for greater than $400. Every SREC represents 1 MWh of electrical energy, so our photo voltaic panels generate about 10 SRECs per yr. Therefore we will count on as a lot as $4,000 per yr in SREC earnings. Up to now we have gotten three quarterly funds totaling $3,647.
If you mix SREC revenues with our electrical energy financial savings, the photo voltaic panels are prone to pay for themselves in about 5 years.
Individuals outdoors of DC most likely will not get such a very good deal. Many states haven’t got an SREC program, and those that do have decrease SREC costs.
After we put in our photo voltaic panels in 2019, they had been eligible for a 30 % federal credit score. That determine dropped to 26 % for 2020. It was scheduled to drop to 22 % in 2021 and to zero in 2022. Nevertheless, Congress simply passed legislation to increase these deadlines by two years. So the 26 % credit score will now be obtainable by the tip of 2022. Then it will fall to 22 % in 2023 and to zero after that.
Then again, the price of photo voltaic panels retains dropping. And a few elements of the nation get extra solar than Washington DC. So when you reside in one among America’s sunnier states, you could discover that photo voltaic panels are a very good funding even with little or no state assist. And regardless, it is good for the setting.
After we determined to exchange our air conditioner in early 2020, we weren’t fascinated by lowering our carbon footprint. The condenser for our previous air-con system was noisy and took up house in our tiny yard. As we made plans to place photo voltaic panels on our roof, we puzzled if we might put the condenser on the roof as properly.
Our preliminary plan to do each on the identical time did not work out. However a couple of months after the photo voltaic panels had been put in, I employed an organization to put in a brand new system on the roof, for the reason that previous one was nearing the tip of its life.
We determined to pay an additional $1,000 or so for a model that doubled as a warmth pump that would warmth our home in addition to cooling it. In complete, the air-con system—together with warmth pump functionality and crane rental—value $12,666. Shopping for the warmth pump probably makes us eligible for a $300 federal tax credit in addition to a rebate from the District of Columbia.
Weeks after the brand new air conditioner was put in, the oil-fired boiler that feeds our radiators sprang a leak, making a puddle of water on the basement flooring. I would been eager to eliminate that previous boiler—and the large oil tank in our basement—for years. The leak accelerated our timetable. Fairly than attempting to salvage our getting old boiler, we determined to exchange it. It was July, so we had loads of time to get a brand new one.
After researching the choices, we determined to get a high-efficiency condensing mannequin. We bought a “combi” unit that doubles as a tankless water heater. It hangs on the wall and takes up dramatically much less house than our separate boiler and water heater had earlier than. It value $10,500. I bought an $825 rebate from the District of Columbia and could also be eligible for a $150 federal tax credit.
Typical boilers waste warmth by sending numerous steam up the chimney. A condensing boiler, in distinction, cools down exhaust gases to show most of that steam again into water, extracting a couple of additional proportion factors of warmth within the course of. These cooler, moister exhaust gases cannot go up a traditional chimney. As an alternative, condensing boilers use a plastic exhaust pipe that stands out of the facet of the home—angled barely downward so the condensing water runs outdoors.