What Are the Steps You Can Take Toward Making Your Home Net Zero Energy?  

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 simple one-unit 12,000-BTU, 29.3-SEER ductless mini-split system from Fujitsu can be found online for $1,961. That’s a small unit, suitable for one room or a garage (a great application!). For our office, we bought a Mitsubishi system in which a single compressor drives three separate wall units, each with its own thermostat.

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 Heat blow 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.

Buyers Benefit From Having an Agent Who Knows Home Systems and Sustainability

One of the reasons I enjoy showing homes to buyers is that I get to educate them about home systems and how they work, as well as identify the sustainable and not-so-sustainable features of each home.

The agents at Golden Real Estate have a thorough understanding of home systems as a result of our combined decades of experience and hundreds of transactions. In addition, we have taken classes on energy efficiency, insulation, solar power and home construction which allow us to serve buyers better when we show them homes.

Together, for example, we toured the model homes at Richards Farms when they were under construction, where we learned, among other things, about that builder’s foam insulation process.

There are so many aspects of energy efficiency and sustainability. Everyone by now knows about solar photovoltaics — creating electricity from the sun. Our office has 20 kW of solar panels, but having solar power is only the beginning. It’s how efficiently you use that power that makes the difference.

Heating and cooling is the biggest user of energy in any home, and the number and variety of HVAC systems have become more extensive and more complicated, and we understand and can explain them. They include: gas forced air heating and compressor-based air conditioning (most common in Colorado and much of the country), hot water baseboard heat, hot water radiant floor heating, wall-mounted heating panels or strips, heat pump mini-splits for both heating and cooling, hybrid heat-pump with gas forced air (which Rita and I have in our home), ground-source heat pump for both heating and cooling (the “gold standard” of efficient heating and cooling) — and let’s not forget heating with wood or wood pellets!

Windows can vary greatly. Double-pane windows may be standard now, but a Colorado company, Alpen, has made a name for itself with triple-pane windows and now quadruple-pane windows.  Recently I wrote about John Avenson’s Westminster home, in which some of his south-facing Alpen windows have micro-etching to divert sunlight toward the ceiling of his kitchen, a high-tech alternative to reflective window shelving, which we saw when we toured a newer building at the National Renewable Energy Laboratory.

Skylights are so 20th Century. Today’s modern replacement are sun tunnels (Solatube is a leading brand), which are great for illuminating interior rooms. Just last week I showed a home with five Solatubes in it, lighting up the living room and an interior bathroom amazingly well from the mid-day sun. My buyer didn’t realize they weren’t ceiling light fixtures until I pointed them out. (We have two sun tunnels in our home illuminating our windowless garage and laundry room, and we have four sun tunnels in the Golden Real Estate office. We don’t have to turn on any lights on sunny days!)

A knowledgeable agent can also point out passive solar features of a home, which others might not recognize. These include proper window configuration, wide overhangs above south-facing windows, thermal masses in south-facing sunrooms, and deciduous trees providing strategically positioned shade in the summer but allowing more sunlight in the winter. I like to see (and point out) cellular shades, especially vertical ones covering patio doors for cold-weather insulation.

Often I notice that the listing agent didn’t mention the features (such as the Solatubes) that my buyers and I recognize as selling points. Of course, when doing the narrated video tours of our own listings, my broker associates and I don’t miss the opportunity to point out those features. And, of course, we are sure to mention those features in the MLS listing.

Many agents miss the opportunity to write a separate description on the MLS for each individual room. It’s not a mandatory field, but it’s the best place to mention a room’s Solatube, heated floor, porcelain tile, hardwood or other feature.

John Avenson of Westminster Is a Committed Teacher of Energy Efficiency

The sponsors of the annual Metro Denver Green Homes Tour, held on the first Saturday each October, are preparing to “go virtual” in case an  in-person tour is not allowed.

John Avenson’s house at 9988 Hoyt Place, Westminster

That will be accomplished by creating online video tours of the most notable “green” homes featured over the past 20 years. Since I’m on the steering committee for the tour and have the equipment and experience from creating video tours of homes for sale, I volunteered to create those video tours, starting with John Avenson’s home at 9988 Hoyt Place in Westminster.

By clicking here, you can view the 41-minute video tour, led by John, which I created last Friday. It is highly educational.

John Avenson

Many people, myself included, have created homes which can be considered a “model” of sustainability, solar power, and energy efficiency, but John is surely the only homeowner who has turned his home into a classroom for teaching it. He even posted pictures and diagrams throughout the house with instructional content about this or that feature, as you will see on that video.

He also hosts monthly Passive House meetings in his home theater which are also streamed online. They can be found at www.meetup.com/Passive-House-Meetup-S-W-Region/

John’s house was originally built by the Solar Energy Research Institute (SERI, now the National Renewable Energy Laboratory or NREL) in 1981 using then-state of the art technology, but John has diligently, and at great personal expense, kept retrofitting his home with newer technology, which he is happy to explain to visitors and which he explains on the 41-minute video.

CERV monitor screenshot

For example, because of increased insulation and Alpen quadruple-paned windows, he was able to get rid of SERI’s supplemental natural gas furnace, installing a conditioning energy recovery ventilator (CERV) which is powered electrically. His grid-tied solar PV system provides all his home’s energy needs and has reduced his Xcel Energy bill to under $10 per month — the cost of being connected to the electrical grid.

Some of the technological innovations featured in my video with John were new to me. For example, the Alpen windows across from his kitchen have horizontal micro-etching which redirects the sun’s rays 90° upward to his ceiling instead of straight through the glass, reducing the need for lighting.

John provided his email address in the video, saying that his “learning center” is open 24/7 and that he welcomes all inquiries and visitors.