Increased ventilation in schools has proven to increase air quality, which can improve student health and focus. However, bringing in more outdoor air means more air must be heated or cooled, often leading to higher energy use and utility bills. One great solution to increase ventilation without the steep increase in bills is the use of energy recovery ventilators (ERVs).
ERVs can reduce the energy used in ventilation by up to 90% by capturing and reusing the heat and energy of the building’s exhaust air. In Minnesota, nearly half of all energy recovery occurs between about 12°F and 45°F, meaning that these units save the most energy during the school year when ventilation is needed most.
ERVs are especially effective in schools
Modeling completed by the Next Gen RTU Initiative shows that primary schools with traditional rooftop units (RTUs) that incorporate ERVs can save around 9% on their energy bill. When combined with a dual fuel heat pump RTU, the number increases to 14% of their energy bill.
Even schools with relatively low ventilation rates, at or below 30%, can see up to a 10% reduction in bills from installing an ERV when replacing an RTU.
Recommendations
ERVs can be integrated directly into HVAC systems or stand alone for exhaust. For buildings with RTUs, the Next Gen RTU Initiative recommends ERVs with an effectiveness of over 60%. Next Gen RTUs has found RTUs with ERVs should always be considered before heat recovery ventilators (HRVs) since ERVs can control both heat and humidity, preventing issues like the common “dirty sock syndrome” in locker rooms.
Although ERVs provide long-term energy and bill savings, upfront costs can be a barrier. To reduce upfront costs, schools are encouraged to apply for the Minnesota Air Ventilation Pilot Grant Program.
You can also visit our Incentive & Financing page to find additional incentives that may apply to the project.
Get Involved
For schools with RTUs that are looking to install ERVs, Next Gen RTUs can offer incremental funding to support the study of new units. We are also eager to hear from schools with RTUs and ERVs about their perspective on how these units work.
Contact us to learn more or share your experience.