The profit in Green is there, just ask the ordinary people who have done and keep doing. And it’s not always about profit yet like any Green incentive, we’ll take it if it helps cover costs and a wise investment. That is where Joe Emerson of Zero Energy Project comes in with an interview on Greening a building! Posts here are usually short yet this is a great Do it Yourselves read to understanding going Green makes dollars and cents. Image is courtesy of Jenifer, Scott and Jonathan at Sea Green Architects in Bethany Beach, Delaware.
In 2018, David Reddy, Lisa Dulude, Eric Thomas, and Alexandra Salmon formed Artemisia LLC to build and operate a vacation rental. Motivated by their personal values and professional skills, they set their sights on making it a zero energy building. Zero Energy Project talks with Artemisia partners about the vision behind the project and its success.
ZEP (Zero Energy Project): Tell us about your zero energy vacation rental.
Artemisia: We built what we believe is the first zero energy nightly vacation rental, an 1,815-square-foot, 3-bedroom, 100% electric grid-tied net-zero energy home.
ZEP: What were your motivations and goals, and to what degree did you meet them?
Artemisia: All four of us share a deep concern about climate change and a strong interest in reducing the carbon footprint of homes. Eric and Alex had built a previous zero energy home in Seattle. Dave and Lisa both work in the fields of sustainability and energy efficiency. They wanted to apply their knowledge by “walking-the-walk” in their own project. We all enjoyed the challenge of pushing the energy-efficiency envelope while sticking to a budget.
Our goal was simple: to build a highly energy efficient, all-electric zero energy design that was achieved on a modest budget and was financially profitable. In the first year of operation, we achieved our goal by producing more solar energy than the home used over a 12-month period.
ZEP: How much additional are you paying per month on your mortgage to cover the added costs of getting to zero and how does that compare to your monthly energy savings?
We weren’t able to get a traditional mortgage for this project because it is owned by the LLC our two families set up. However, if we were to finance the $26,000 price difference of getting to net-zero over 30 years at 3.92%, it would add about $123 per month to the mortgage bill. When you factor in the $190 per month utility bill savings, we would actually come out $67 per month ahead by going the zero energy route, right from the very first month.
ZEP: Can you break down the added cost to get to net-zero versus a similar home built to code?
Artemisia: In general, we tried to prioritize energy efficiency and rooftop solar over costly finishes, and in so doing, we believe we kept our construction budget in line with or below other vacation homes in the area. That said, we estimated that building our home net-zero cost about $26,000 more than if we had built the identical design to code-minimum standards.
The 5.4 kW PV system, with installation, was just under $20,000, or about $3.50/Watt. The remote location was a factor in a higher system cost. However, the cost of the solar was offset by a federal tax credit of 30% of the cost of the system, as well as a small production incentive we will receive annually from Washington State.
We used Structural Insulated Panels (SIPs) for the building envelope. They cost up to 20% more than traditional 2×6 framing. SIPs may have added about $5,500 to the cost of our home, although we did not get bids for traditional framing. One of the benefits of SIPs construction is lower labor costs, but we found our labor costs to be on par with stick building because we had to bring in a framer familiar with SIPs construction from out of state.
We chose vinyl-framed windows, which were less than wood or fiberglass. However, to achieve our zero energy goal, we went with triple-pane instead of double-pane, which added about 20% or $2,500 to our window package price.
Our fresh-air ventilation system makes use of a LifeBreath heat recovery ventilator (HRV), which cost about $3,900 installed. If we had gone the code-minimum route, we might have gotten away with a whole-house, exhaust-only system for less than half that price, but we would have paid more in heating and cooling costs, and it could have led to cold drafts in the winter.
We chose an 80-gallon Voltex heat-pump water heater from AO Smith, which retails for about $2,100. A low-end propane water heater costs about $1,200. Even though the initial cost was higher for the heat pump water heater, it was a far better deal because propane is more expensive than electricity and the heat pump water heater is significantly more efficient than the propane water heater. Choosing efficient electric appliances, such as our heat pump clothes dryer and induction range, added about $1,000 over their less-efficient electric or propane counterparts.
A back-of-the-envelope calculation shows that we spent roughly $32,000 to meet our net-zero goal, $6,000 of which came back as a federal tax rebate, for a net total of $26,000. Our construction costs totalled about $300,000, so we would estimate our incremental cost of achieving net-zero to be roughly 8.7%.
ZEP: How do you calculate your saving on energy bills each month?
Artemisia: We pay only the $32 base service charge for our local electric co-op and no propane or gas bill. Our utility estimates the average monthly electricity bill in the area to be $120. The cost to refill a propane tank would average out to about $100 per month. So we would estimate our average monthly energy savings to be about $190. For a limited time, Washington State will also be paying us a production credit for each kilowatt hour our solar panels generate, which we estimate will add up to about $1,200 per year.
For the complete story with graphs and contacts, click here and thank you Joe. Stay tuned for more on Green building on the Coast of Delaware!