I have expressed dismay in the past that builders of new homes in our area are not getting “with it” when it comes to incorporating the latest thinking and technology regarding energy efficiency.
Builders boast their Energy Star appliances and lower HERS scores, but they are still, for example, installing gas forced-air furnaces instead of heat pumps, gas water heaters instead of heat pump water heaters, and gas cooktops or ranges instead of induction cooktops.
The Geos Community in Arvada provided proof of concept for the all-electric solar-powered, net zero energy home, and homes in that small, privately developed neighborhood have been featured for several years on the annual tour of “green homes.” But no production builder here has picked up on that concept, and when another builder acquired the undeveloped parcels at Geos last year, the first thing they did was bring a natural gas pipeline into the community to serve their new homes, greatly upsetting the happy homeowners of the original net zero energy Geos homes, which purposely have no natural gas lines.
Above is one of KB Home’s all-electric homes in Menifee CA, a smaller city south of Riverside. Not only is every home in that subdivision “net zero energy ready,” but they are tied together in an electric “microgrid,” designed to power itself cooperatively should there be an outage in the larger electric grid.
In the garage you can see both an EV charger and a wall-mounted battery backup system. The small print on the sign reads: “This all-electric, solar-powered home is equipped with smart technologies and a backup battery, plus community microgrid connectivity designed to help maximize home energy efficiency and comfort.”
Meanwhile, here in Colorado, neither KB nor any other builder, to my knowledge, is even offering heat pump HVAC units or heat pump water heaters as upgrades.
A reader who has been following my columns about fire resistant home construction, including concrete, sent me information about a Houston TX builder, Everlasting Homes Building Group LLC, which uses RSG 3-D structural concrete insulated panels to build homes which are not only fire resistant but also meet “extraordinary levels of excellence in energy and performance.”
At the top of its excellent home page, EverlastingHomesGroup.com, is the following statement: “Our vision is to design and build the most comfortable, healthy, resilient & sustainable living spaces dedicated to creating the best net zero energy homes and communities for our future.” They promise to build homes “resistant to hurricanes, tornados & floods, extreme cold / hot weather, earthquakes & fires, wood-destroying insects, and allergens, pollens, molds & dust.”
I don’t know anyone who doesn’t like the idea of saving money, which will happen when you convert your home to “net zero energy.” So, what are the steps you can take to get there?
“Net zero energy” means that your home generates more energy than it consumes. With “net metering,” your electric meter runs backwards when your solar panels generate more electricity than you’re using (on a sunny day), then runs forward at night, resulting in zero (or less) net consumption of electric power.
Solar power gets more affordable every year. When I purchased my first 10-kW solar photovoltaic system 15 years ago, the cost was over $60,000, but Xcel Energy gave a rebate of $4.50 per watt, so I got a check for $45,000 from the utility, reducing my net cost to $15,000. Nowadays that same system would cost as little as $15,000 with no Xcel rebate but a 26% federal tax credit.
While you can generate your own electricity, you cannot generate your own natural gas, so terminating natural gas service is key to achieving net zero energy. This involves some major system changes if you are currently heating your home and your water using natural gas, cooking with gas (including with a gas grill) and have a gas fireplace.
There are electric alternatives to all of these uses of natural gas, and you’ll appreciate that eliminating natural gas also eliminates the possibility of a gas explosion and of carbon monoxide poisoning (unless you have a gas powered car).
Heating your home with electricity used to mean installing baseboard resistance heating units in each room, but that is so 20th century. Nowadays electric space heating is done far more efficiently (and evenly) using heat pumps.
Gas forced air furnaces and water heaters are considered to have a 15-year life expectancy, so when yours fail, think of that as an opportunity to adopt heat pump technology for both functions. And a heat pump eliminates the need for a separate A/C unit, since it heats and cools.
Gas furnaces and water heaters generate heat by burning gas. A heat pump moves heat, similar to what A/C does. (How heat pumps work) It cools your home by moving the heat out of your house. If you put your hand over the external compressor unit while it’s cooling your home, you will feel the heat that was moved from inside your home. In heating mode, the process is reversed, and the heat pump moves heat from outdoors into your house. It may surprise you to know that when it’s freezing outside there is actually heat that can be moved from outside to the interior of your house, but it’s true. (Heat pumps work in extremely cold climates) Our office has been heated solely by heat pump since November 2017, and ever since there has never been a day when the system failed to keep our office at 70°F or warmer.
A heat pump water heater (which I installed at our home) has the compressor built into the unit, above the tank. You can feel cool air emitting from it when it is heating water. I suggest putting it in a wine cellar where it’ll keep the room cool without buying a separate A/C unit.
For cooking, you’ll be amazed and delighted by the induction cooktops that are now widely available. I saw them used on a cruise ship for both cooking and warming surfaces, and the chefs loved them. (Modern cruise ships have eliminated natural gas because of the fire hazard.)
An all-electric home will, of course, demand more electricity, but Xcel Energy now allows you to install enough solar panels to generate double your electrical usage over the prior 12 months. That is more than enough to cover your new electric space heating, water heating and cooking needs, with capacity left over to charge an EV, too.
An important first step in pursuing net zero energy for your home is to reduce your need for energy, and the easiest and cheapest way to do that is to improve your home’s insulation. I had Dennis Brachfield of About Saving Heatblow cellulose insulation into the exterior walls (not just the attic) of a 1940s bungalow I owned, and I was astonished at how much more comfortable the house became. Even if your exterior walls have batt insulation in them, there is still space in the walls to blow in cellulose. (How to insulate an old house)
I learned something interesting from that experience. We all know that walls can radiate heat, such as a brick wall in bright sunlight. Well, walls can also radiate coldness, or suck heat. The air temperature in my bungalow before and after blowing in insulation was the same, but I felt warmer and burned less gas.
You can go beyond improving the insulation of your exterior walls and attic. There are numerous places that allow cold into your home, especially around your windows. Whether or not you install triple-pane Alpen windows, as we did at our office, caulking around the window frames and elsewhere can reduce the energy needed to heat your home.
A blower door test done by a contractor will identify the air leaks in your home. Insulating your attic with blown-in cellulose and your crawlspace with plastic sheeting will also reduce your home’s energy needs whether from gas heating or your new heat pump. (Insulating crawl spaces)
Of course, many homes, especially in older neighborhoods, can’t benefit from solar power because of shading from trees or insufficient south-facing roof area, but you can purchase community solar. (This is also a good solution for condos which have no roof at all.)
The way community solar works is that you invest in solar panels that are part of a solar farm in some distant pasture. The electricity generated by your panels in that remote location is credited to the electric meter for your home or condo. One advantage of community solar is that when you move, you only need to change which meter gets credited with your solar production.
Other ways of reducing energy use include replacing CFL or incandescent light bulbs with affordable LED bulbs and “daylighting” your home or office. (Batteries + Bulbs sell 8-packs of 60W LED replacement bulbs for $6.49, tax included, after $15 instant rebate.) We have “sun tunnels” in our home and office to bring daylight into interior spaces. In fact, on a sunny day we don’t need to turn on any lights in our office. It’s great— and saves energy. We had Design Skylights of Evergreen install Velux sun tunnels at both home and office.
Would you like one of us to visit your home for a private consultation about the sustainability possibilities in your home? Email me at Jim@GoldenRealEstate.com.
The Geos Community located southwest of Indiana Street and 72nd Avenue in Arvada is a shining example of what’s possible in net zero energy home construction.
All Geos homes are solar powered and have no natural gas service. Heating and cooling is provided by ground source or air source heat pumps. Water heaters utilize heat pumps, not gas, and all the homes and townhouses are built according to passive solar design standards.
Two Geos homes were on last fall’s Metro Denver Green Homes Tour, and you can view narrated video tours of them by clicking on that link.
Now a developer has bought the remaining land within the Geos Community but is intending to install natural gas service in all the homes they will build. Naturally, the current residents are quite upset about this turn of events and are hoping to convince the City of Arvada not to allow this diminution of the original intent of Geos to be a strictly net zero energy community.
Visit www.DiscoverGeos.comto appreciate this community’s net zero energy mission.
Rainer W Gerbatsch, a Geos resident, in an email to Linda Hoover, Senior Planner for the City of Arvada, expressed concern about the new developer’s plan to deviate from the community’s principles by installing natural gas in future homes. Here is Ms. Hoover’s emailed response:
Thank you for your strong interest in your community. I was forwarded your concerns regarding the new upcoming development in the GEOS Neighborhood and I will do my best to address your comments. The GEOS Development was approved 12 years ago. I took over as the staff planner for this project in 2014 when the previous planner left the City. When GEOS was approved, it was intended to be a sustainable community and Norbert Klebl tried for many many years to obtain the funding to make that happen. To date, the only homes constructed out there are on Block 10 which has a mix of the staggered “checkerboard” single family detached homes and townhome units. This totals approximately 38 units out of the 282 planned. While the existing homes have a number of sustainable features, SunStudios (Architect) and Laudick Engineering are telling us that marketing of this concept has been very difficult in part due to the economics of having a development without gas service and other unique features of this development, such as having custom designed mechanical heating systems, etcetera. Most of the larger home builders want developments that have gas service. As you may know, this development went through a bankruptcy last summer. The new owners are currently in the process of working with a new builder – Dream Finders Homes. As Dream Finders comes on board, they are planning on keeping many of Norbert’s original concepts, but wanting to make some adaptations to make it economically feasible. The lot layout which has the staggered checkerboard placement of single family detached homes in the middle of the block and townhome units on the ends of the block will remain as originally intended. As a result these homes will continue to have the same architecture and passive solar design. In addition, solar panels will be placed on the rooftops and appliances will be energy efficient. These new homes will follow the Building Code to construct energy efficient homes. The building codes adopted by the City already allow various paths/choices to construct very efficient (minimum energy code) all the way to net-zero buildings – the traditional codes were followed to build the first 38 units. It is my understanding that DreamFinders would prefer to have the project served by gas, but are still looking into the economics of this issue.
This development was and still is zoned PUD (Planned Unit Development) which has its own unique design requirements rather than following the standards in the City’s Land Development Code (LDC). The GEOS Design Book states that “architecture should strive for Energy Self-Sufficiency and the avoidance of Fossil Fuels.” It also identifies net zero homes as one of the intended goals (not requirements) and further clarifies that that “goal can be achieved by combining good solar orientation and good insulation with geothermal or solar thermal heat, and photovoltaics.” However, it is silent on the issue of gas service.
As a result, we would allow the development to be built without gas service (just as was done for the first phase of GEOS) provided alternatives were ensured. However, no restrictions were included in the Design Book or on the project approvals that prohibited gas service. Passive systems, energy efficient buildings, heat recovery ventilation are guidelines not requirements.
Sent 5/13/2021
Here is Rainer’s response to Ms. Hoover’s email:
I am familiar with the background of GEOS and the more recent events. Contrary to your statement that net-zero homes are difficult to sell, recent sales activity of homes in GEOS show just the opposite – there is high interest in these homes resulting in higher than expected returns for the seller and very short listing periods. It would appear that cited developer/builder statements are either uninformed or demonstrate an unwillingness to engage in construction practices that are a win-win situation for the builder, the buyer, and perhaps most importantly, the environment we all rely on. Also, I contacted and asked the architect whether he supported the cited developer/builder statements, and he responded that he did not.
Studies of completed net-zero buildings in Colorado (including GEOS) conducted by SWEEP also show that the initial cost of net-zero, all-electric homes at this time is on par with so-called traditional (polluting) construction. Net-zero construction represents a clear choice once future buyers understand that (1) these homes represent (already at this time) substantial yearly savings in energy use/expenditures (fossil fuel based energy costs will only increase as the cost of natural gas escalates based on the need to curtail and ultimately eliminate gas as a potent driver of climate change), and (2) eliminate health risks related to exposure to gas appliances and fossil-fuel burning heating devices that generate a variety of air pollutants which have been linked to cancer, decreased lung function, heart disease and a host more diseases. While these risks have been recognized for some time, they are finally receiving mainstream media attention. However, resolution is not possible without the engagement of all levels of government with developers/builders on more responsible construction practices. In summary, net-zero construction is currently superior to traditional construction because of reduction in emissions, elimination of health issues traced to fossil fuel based energy use in homes, and escalating future costs of fossil fuels, particularly natural gas.
GEOS’ prominence as a leader in de-carbonized and sustainable community living is recognized locally (we have been visited by members of sustainability committees of several Colorado towns), and nationwide (CNN’s chief environmental correspondent Bill Weir visited GEOS; CNN will be airing a nationwide broadcast on GEOS, highlighting its features as the model for home construction to achieve decarbonization and healthier interior air quality for residents). In that vein, responsible governments on all levels are preparing and committing to road maps with the goal to rapidly reduce emissions in home construction through elimination of fossil fuels, increased efficiency in appliance/lighting and heating/cooling, as well as the production of on-site renewable energy. In order to have an effective road map, commitments are required which mean nothing less than elimination of fossil fuel use in all new buildings. Consider that the IEA has just issued a special report; this statement stands out: Fatih Birol, the IEA’s executive director and one of the world’s foremost energy economists, told the Guardian: “If governments are serious about the climate crisis, there can be no new investments in oil, gas and coal, from now – from this year.”
It is 2021, and permitting a developer/builder team the inclusion of natural gas infrastructure for about 250 new homes, based on questionable developer/builder concerns of perceived marketability or economics, thereby locking in emissions for the life of the buildings, subjecting owners to health risks related to gas pollutants and escalating energy costs (not considering future mandated retrofits based on the trajectory of climate induced changes), is not responsible, sets the wrong signal and constitutes a serious setback in rising to the challenges of the climate crisis.
The City of Arvada has the opportunity and responsibility to address the climate crisis, facilitate the transition from fossil fuels to renewable energy, and protect the health of residents from natural gas pollutants. Both can be realized, simply and effectively, through rapid adoption of policies and building codes that support state and nationwide goals in emission reductions. We urge you to demonstrate your commitment to a sustainable future not only through elimination of the fossil fuel infrastructure for the next phase(s) of GEOS, but through a city-wide commitment to net-zero construction, fossil-fuel free construction.
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