Energy Recovery Ventilator Technology for Commercial Buildings
As concerns about energy efficiency and indoor air quality grow, technologies emerge and evolve to meet these concerns. In the commercial arena, energy recovery ventilator (ERV) technology is providing building owners and managers with a cost-effective way to increase ventilation while also holding down heating and cooling costs. Here is a brief overview of energy recovery ventilators and how they can benefit your commercial building and its occupants.
The Need for Energy Recovery Ventilator Systems
In a commercial setting, air exchange must occur to remove old, stale air and bring fresh, clean air into the building. Indoor air in a commercial space can accumulate particulates, odors, moisture and fumes that can harm occupants or the structure of the building itself. These materials must be removed through ventilation, while an equivalent volume of air is brought in as replacement. A significant problem with some ventilation systems is that large amounts of heating and cooling energy can be lost when stale air is exhausted out of the building. This occurs because even stale indoor air will still be warmer or colder than incoming air, depending on the season. Previously, little could be done to make up for this energy loss except to adjust the settings on the HVAC equipment to compensate. This solution may help maintain indoor temperatures at tolerable levels, but it drives heating and cooling bills much higher than necessary. An ERV will help prevent the overuse and waste of energy in these types of situations.
How Energy Recovery Ventilator Systems Work
An energy recovery ventilator is designed to recycle and reuse substantial amounts – up to 80 percent – of the heating and cooling energy contained in exhaust air. This reduces waste and cuts down on the amount of extra work your HVAC system must do. In summer and winter, incoming ventilation air will be either hotter or cooler than outgoing exhaust air. An ERV effectively transfers a major portion of the energy in the exhaust air to the incoming fresh air, either cooling or heating it as appropriate. Since the temperature of the ventilation air has been adjusted before it reaches the inside of your commercial space, the HVAC system doesn’t have to work as hard to make up for the difference in temperature between the incoming and outgoing air.
There are two major types of energy recovery ventilation system: heat recovery ventilators (HRV) and enthalpy recovery ventilators, usually referred to under the general term of energy recovery ventilator. Both systems rely on a configuration that sends both incoming and outgoing air through a heat exchanger. Within the heat exchanger, the two streams of air pass across specialized plates or similar surfaces where energy transfer can take place. The two streams of air do not mix, but heating or cooling energy is exchanged as appropriate. In the summer, incoming air is cooled by the outgoing exhaust air. In the winter, the opposite occurs, with incoming cool air being heated by energy from the exhaust.
An additional feature of an enthalpy-based ERV system is that it transfers some moisture to the incoming air. This exchange of humidity can be beneficial during the winter months or in areas of the country where the climate is often dry. An energy recovery ventilator is especially useful in newer buildings that are very thoroughly sealed against air leaks and energy loss. In these structures, ventilation is the major source of energy loss. An ERV takes best advantage of the building’s tight envelope and reduces the major source of waste that can reduce the facility’s energy efficiency.
Our goal is to help educate our customers about Plumbing, HVACR, Fire Protection and Alarm Systems in Mechanical, Commercial and Residential settings. For more information on the benefits of using an energy recovery ventilator to improve HVAC performance and reduce your monthly energy costs, and to view projects we’ve worked on, visit our website!