Net Zero isn’t just a goal – it’s a responsibility
In the face of increasingly austere budgets and an uncertain economic future, school systems are looking for creative ways to reduce expenditures. Costs to operate facilities are second only to personnel costs, but have comparatively little impact on teaching and learning. It’s understood that wholesale reductions in utility consumption would significantly impact the bottom line…and potentially improve outcomes for student success. Sounds like a win-win, right?
But getting there means making some big changes in the way we do things. The next 50 years will see dramatic shifts in energy supply, demand and cost. Demand for energy will multiply in developing nations. Periods of higher-than-normal inflation (up to 10-12%) is not only possible, but expected by some forecasters. Supply of fossil fuels will diminish dramatically – and costs will escalate proportionately. It has been speculated that the water supply in Texas, where I’m based, will diminish with population growth and from the effects of global warming. So, what does all this mean? It means that we need to start designing to minimize energy consumption now, as a rule of practice, rather than looking at this as a “trend.” Instead of chasing “green” designations, we should be focusing on incorporating sustainable concepts into design as a matter of course. There is a way to design facilities that can move them towards “net zero” with minimal costs up-front.
Richard J. Lee Elementary School
What is Net Zero?
Net Zero is essentially a way to mitigate impacts. It means that the total amount of energy used by the building on an annual basis is roughly equal to the amount of “renewable energy” created on the site. Sounds good, right? But for many school systems – particularly in the public realm – the idea of Net Zero sounds out of reach. So how do we get there?
- Start with the site selection. First, understand the soil and topography conditions of your potential site. Are there multiple access points to the site for pedestrians and vehicles? Are utilities nearby and, therefore, easy to bring onsite?
- Consider the physical design of the facility. Orient the building to maximize daylight harvesting. Keep the building form/massing compact and reduce the volume of surface area. Design the building envelope as thermally efficient as you can, while balancing the quantity, shape, and size of your windows (and locating them to maximize daylight into the classrooms).
- Don’t forget lighting, heating, and cooling systems. Light fixtures should be as efficient as possible – make sure you aren’t over-lighting the building. If you invest in geothermal systems you can harvest free heating/cooling from the earth. Energy recovery wheels can take expended energy and make it work for you by capturing energy from waste products.
- Try (at least) to control the little things that contribute to energy load. The strategy with the biggest impact but the hardest to control is the behaviors of the occupants and maintenance teams. Did you know that controlling the load on the electrical plugs is the biggest culprit? Laptops consume less energy than PCs. Hidden coffee pots, foot warmers, and mini fridges all add to the electrical load demand. Try to educate staff on the effects these appliances can have on energy consumption, and see what results you can report when the team reduces its use. Money spent on building system controls (occupancy sensors, DDC controls, etc.) also allows a school district to virtually eliminate excess energy consumption throughout the entire day and night.
- Incorporate renewable energy sources to offset energy consumption. Solar panels on the roof harvest massive energy in southern climates, which are abundant with sunlight. Wind power is equally viable in the wide open plains of the Midwest. Thermal properties of the earth have made geothermal heat pumps a logical choice in many geographic regions. Discover what options could possibly work for you. Resources such as DSIRE, the National Associate of State Energy Officials, or the EPA’s Green Power Partnership may be a helpful place to start.
So what’s the bottom line? Schools truly can reduce energy consumption and offset it with renewables to reach net zero. Add up all your sources of energy consumption (heating, lighting, cooling, equipment, pumps/fans, hot water) and divide by your gross building area to determine your Energy Use Intensity (EUI) in kBTU per square foot, per year. Add up the amount of renewable energy you capture on your site with your facility. If they are equal …congratulations! You have achieved that perfect balance: Net Zero!
About the Author
Jennifer Henrikson is an architect and project director in our Houston, Texas office. She focuses especially on educational facility design.More Content by Jennifer Henrikson