Gasoline prices have finally started to fall giving many Americans a well-deserved break for their pocket books, but another great way to drive down those energy dollars is within the home or business by reducing energy spending.
Residential and commercial use accounts for 41% of the energy consumed in the United States, according to the National Academy of Sciences.
Building energy-efficient homes and structures has been the driving passion of Associate Professor Tim Hemsath’s career. He has researched, presented, published and taught on this subject, to the point he can probably lecture about this topic in his sleep.
“I’ve always been interested in sustainability. You could say I was raised with those values,” Hemsath commented. “When I was a kid, we would walk to church along the highway and my dad would have the family pick up trash. So before there was an Adopt a Highway program there was the Hemsath program.”
Hemsath explains his desire to make a sustainable impact only intensified in college when he decided to go into architecture.
“I wondered where I could have a measurable impact and how it would affect design. How can we better design our buildings with a greater understanding of its impact, and how can we alter that impact so it creates a positive difference?”
Energy is measurable, so Hemsath knew he could set clear objectives and goals for his designs and his research.
“You can use computer modeling to understand the operational energy consumption of a building and then in theory, design buildings that are more efficient.”
There is no one silver bullet to achieve an energy-efficient building. Hemsath tells his architecture students an efficient building depends on various factors such as climate, its size, the building design, how it is used, etc.
“There are too many factors involved to say this one thing can save you x amount in energy because every place in the world is different, every building is different. What I like to say is you have to understand all your factors before you can make any conclusions.”
Hemsath’s resumé regarding energy-related projects is quite extensive. His research started in 2006 with the College of Engineering on a project developing energy-efficient housing prototypes. He later served as the principal investigator on a Nebraska Research Initiative to increase research capacity surrounding zero-net energy at the University of Nebraska.
Hemsath explains he has seen an upward trend in designing sustainable buildings at the national level.
“I see the use and demand growing,” Hemsath observed. “When I started researching and teaching about sustainability in 2006, only homes were achieving high-efficiency results. Now you see large facilities, campuses and communities also meeting these standards. The capabilities and the technology are all there. It really comes down to market demand and the desire from everybody’s standpoint to make it happen. It’s a matter of the right dominos falling in the right places.”
Many factors are driving this trend including regional and national legislation with energy codes, building standards and emissions restrictions. Furthermore, 2009 American Recovery and Reinvestment Act stimulus funds were tied to local energy code adoptions for its recipients. Also some municipalities such as Minneapolis and Chicago have implemented benchmark ordinances requiring energy consumption reports from commercial buildings. At this point, Hemsath says these reports aren’t used to reduce consumption but if history repeats itself, he can see these established reporting mechanisms eventually being used to for energy conservation similar to the origins of the 1970 Environmental Protection Agency’s Clean Air Act.
But even with all these government entities pushing the market to be more efficient, Hemsath believes design professionals have to be at the forefront of that effort.
“We are the ones who design the buildings. We are the doers, the innovators.”
When designing new buildings, to achieve a zero-net energy building, there are three action steps Hemsath recommends:
Use energy efficiently. Design for solar, daylight, climate and design the appropriate envelope. Build the most energy-efficient building possible.
Minimize energy use. Incorporate energy-efficient systems and install technology such as occupancy sensors.
Apply renewable energy. Produce energy through such mediums as photovoltaic, thermal and wind.
However the greatest need for energy conservation efforts are actually in established buildings. It is estimated that ¾ of our current buildings will be renovated by 2050. Hemsath says that is an untapped market for innovation. For those looking to improve the efficiency of their home there are key elements he suggests.
Have someone evaluate the home for energy efficiency. Many energy companies offer this service.
Insulate the attic and walls and make the home airtight by sealing window trim and baseboards.
Make sure the home has a well-designed duct system with a balanced supply and return air flow. Make sure the ducts are sealed so there are no leaks.
Hemsath says if the home owner can only afford to do one thing, he says the number one thing they should do in Lincoln’s climate is improve the home’s insulation or airtightness.
With all his teaching and research experience, Hemsath is often regarded as an expert in his field. He has spoken internationally and nationally on issues of energy-efficient design and using building energy modeling. He has several local engagements this semester including a talk entitled “Zero-net Energy Homes” at the March Nebraskan’s for Solar meeting and then another presentation at the Nebraska ASHRAE Chapter on "Building Energy Modeling in Design," date to be determined.
Furthermore, Hemsath has several published works on this subject including two recently in Science Direct entitled "Building Design with Energy Performance as Primary Agent" and "Sensitivity Analysis Evaluating Basic Building Geometry's Effect on Energy Use."
Hemsath will have a book coming out in early 2017 published by Routledge entitled “Energy Modeling in Architectural Design.”
With the outlook of energy consumption projected to increase, Hemsath’s work couldn’t be more important or timely.