Action to address climate change started happening in some areas of the U.S. roughly 20 years ago. Certain businesses started to adapt their spaces, and build more efficient ones, recognizing serious long-term cost savings. Now, gradually, residential homeowners are beginning to recreate with sustainability in mind.
The trick for a Minneapolis homeowner – whether pursuing a new build or a renovation or retro-fit – is how to find local developers who can offer the smartest sustainable impact. MPLS Green is beginning deeper conversations with some of them (see Resources below).
In this conversation with architect Ron Fergle, owner of Solart Inc., his passion for the technology and big-picture of the changing landscape of sustainable building is obvious. He is a detail-oriented man and cycling enthusiast who has painstakingly updated his century-old Uptown home to add space and provide modern conveniences, but at the same time maintain its original style. This included finding authentic finish materials with regular visits to Bauer Brothers and other local businesses that sell repurposed building products. He is an MIT graduate who travels to conventions around the world to give presentations on sustainable design, as well as to learn more about new green building products and sustainable construction practices.
Q: What are big-picture changes that interest you right now?
1. Material Selection
I like how the public is starting to look more at the whole picture of how we construct and use buildings. This includes how much energy goes into creating the materials we use and how much energy it will consume during the life of the building.
In the past, a lot of the discussion was simply on the first-costs. Now we’re looking at the total costs incurred over time. This helps select materials that are better in the long run.
We’re also more aware of the environmental impact of the materials we use – not only how they affect the environment as a whole, but how building materials can influence the health of the occupants. Cradle-to-cradle, life-cycle costs, environmental footprints, and holistic design are just some of the terms for concepts that consider energy usage and environmental impact of materials.
2. Water Impact
I also think we’re changing how we look at water — how much water we use and how we affect the quality of the water we put back into the environment. We’ve had a lot of focus on energy issues (rightly so), but I think water is going to be the next ‘hot topic.’
Water quality issues are becoming increasingly important to local governments. In our area, I like that both the city of Minneapolis and the Park & Recreation Board are looking seriously at site-water runoff. This is when a site has too much surface area comprised of impervious materials, and rainwater that can’t be absorbed quickly enough into the ground finds its way into storm sewers and from there into our lakes. This runoff carries the oils, chemicals, pesticides, garbage, and other pollutants that collect on the roadways and parking lots and deposits them in our lakes and waterways.
The Park Board has been using permeable pavers for a few years. These help rainwater infiltrate immediately back into the ground without having to flow into the sewers. The City is conducting regular street sweeps to help collect pollutants and contaminants before they get washed into our sewers and lakes. And, some neighborhood groups (like East Isles) are encouraging residents to create raingardens. This is where the rain that falls on a property is directed to an area where it can collect and absorb into the ground without creating surface runoff. These raingardens can be designed to be beautiful amenities.
3. Solar Energy
Another big-picture change is what’s happening in the solar industry right now. It’s quite exciting. Photovoltaics have been developed that are transparent, flexible, and come in different colors. Some of these products are just hitting the market.
The traditional rectangular panels are also becoming more efficient and are highly cost effective. The best part is, the electricity these photovoltaic systems produce is clean – there are no carbon compounds, sulfurs, mercury, or other toxic emissions released into the environment as they create electricity.
Europe has been implementing solar effectively for quite a while. It’s nice that Minnesota is helping to lead the U.S. in this process with our 2013 state law mandating that major utilities generate at least 1.5% of their electricity from photovoltaic sources.
In addition, where homeowners, renters, or businesses don’t have sites suitable for photovoltaic installations, they can now get the benefits of solar energy by participating in off-site community solar gardens. (Much more on that to come at MPLSGreen.)
Q: Explain how our buildings could use energy better than they often do.
- using energy-efficient appliances
- improving insulation to reduce heating and cooling costs
- having automated controls to reduce energy consumption (for example, motion sensors can turn lights off when no one is present, and digital thermostats with set-back settings can reduce heating loads in winter and cooling loads in summer by not having to heat/cool the building when occupants are asleep or not in the building).
But many homeowners don’t realize the importance of reducing air infiltration (and exfiltration) that occurs through the building envelop.
The building envelop consists of the walls, doors, windows, roof — the “membrane” that separates the inside of the building from the outside.
While insulation is an important component of a building envelop — it helps to reduce heat transfer through the solid envelop itself — if the heated (or cooled) air from the inside of the house is constantly getting blown outside through leaking doors, windows, or gaps in the “membrane,” then energy has to be used to heat (or cool) the new air that is leaking into the house to replace that air being blown out.
This is why it is important that:
- gaps around windows are caulked,
- electrical outlets located in exterior walls are installed to prevent air leakage,
- weather stripping is located at doorways.
One way to think of it is to imagine a thermos bottle. When the lid of the bottle is on tight, the liquid inside stays hot (or cold) for a long period of time. But when the top is removed, the liquid quickly cools down (or warms up) no matter how well ‘insulated’ the bottle material is. A house is the same way. Keeping it “tight” can save a lot of energy.
Buildings can also use energy better if heat exchangers are used. In building ventilation systems, an air-heat exchanger takes the energy contained in the exhaust air and transfers it to the fresh air coming into the building ventilation system. (Even though it’s good to reduce infiltration/exfiltration, some amount of fresh air is required to keep unhealthy contaminants from accumulating inside.)
I think a new trend is going to be capturing the energy leaving a building through the waste water. Some products are already on the market that do this. Just imagine how much energy is being flushed down the pipes during a hot shower or after a hot bath, or when the dishwasher is running.
A related topic is how buildings can use different sources of energy that have a less negative impact on the environment.
Currently the main sources of fuel used to generate the electricity we get from utilities are coal and natural gas. These sources emit large quantities of carbon dioxide, sulfur, mercury, and other toxic materials into the environment.
It is also highly inefficient to transfer the electricity long distances from the utility power plant to the end location where it will ultimately be used. If we can reduce our dependence on these fuel sources, at least to some extent, and generate the power closer to where it will be used, then we’re having a more positive impact on the environment.
There are a number of energy sources that are “cleaner” than coal and natural gas. In terms of sources that can be utilized on-site or directly on a building itself, I see geothermal systems and photovoltaic systems as having the most potential.
This essentially uses the ground as an energy storage medium. Heat is transferred back and forth depending on the season. In summer, the heat from inside a building can be transferred into the ground. In winter, the heat in the ground can be used to warm the building.
Naturally there are design parameters that need to be taken into consideration, but if done properly geothermal systems are highly reliable. They can be used for heating and cooling houses as well as large office buildings.
There are a number of residences along Lake of the Isles that use geothermal systems. Manitoba Hydro Place is an excellent example of a large office building that utilizes geothermal. It’s even located in a climate more challenging than ours!
Photovoltaic (PV) Technology
This is the other energy source that I see as having great potential for providing electricity directly at a building location (also known as “DPV” for Distributed Photovoltaics).
Most people are familiar with the traditional roof-top PV array – long rows of rectangular black panels angled towards the south. They reliably produce large amounts of electricity without polluting the environment. (Quite a few building roof-tops in our area are covered with these, including the Minneapolis Convention Center.)
I’m most excited about the new photovoltaic cells now hitting the market. They’re not what most people think of when they imagine solar cells.
- The new cells can come in different colors, from red to green to gold.
- They can be flexible, like rolls of carpet you lay out on a roof.
- They can be integrated into building materials themselves (some are called “BIPV” for Building Integrated Photovoltaics, and others “BIOPV” for Building Integrated Organic Photovoltaics). For example, there are shingles and roof tiles that are also PV cells, and colored wall panels that you wouldn’t even know were PV unless someone told you.
- There are photovoltaic cells that are translucent and others that come in different degrees of transparency.
The most exciting to me are the ones that are transparent. The transparent cells look like ordinary glass, but they’re actually photovoltaic cells that are generating electricity. These transparent cells are not yet on the market as a building product, but that can’t be too far away. I expect to see them in the near future as coverings on the surface of ordinary smart phones. MIT and UCLA are doing some impressive research in the production of transparent PV cells right now.
Resources About New Solar Technologies
COMING UP: More with Ron Fergle and other experts on how to pick the right sustainable designer for you
Related MPLS Green Resources
- Green architect Alex Haecker, AWH Architects
- Energy efficient landlord Timothy Springer
- MetroBlooms raingarden expert Rich Harrison
- A Zero-Energy House in Our Backyard
- Home Designer Michael Anschel, Otogawa-Anschel
- COMING: A local passive house designer
- COMING: Converting a century-old house
- Where are the Minneapolis LEED homes?
- The LEED commercial buildings in Minneapolis
In Our Climate Change Series
- The Minneapolis Climate Action Plan
- Do you know what your home energy costs are?
- How Edison High School (NE MPLS) is making change happen
- The costs of energy and air quality in our schools
- Portland, Oregon: Catching up to our older and wiser sibling
- How does Minneapolis become zero waste?
- What is a carbon price and why should I support it?
- The cost impact of LEED and Minnesota Green Star
- Typical Minneapolis household expenses for gasoline, oil, electricity
- Why plants and trees matter
- Progressive multifamily and affordable housing
- Creative use of garbage