Heating, Ventilation, and Air Conditioning
Heating and Cooling
Heating, cooling, and ventilation accounts for about 39% to 54% of the energy use in a typical office. Larger offices have more cooling because of the internal heat gain from people, lights, and office equipment. Either way, heating, ventilation and air conditioning (HVAC) is a large part of energy bills. The purpose of an HVAC system is to heat, cool, control humidity, and bring fresh air into a building. Employee and customer comfort is the main priority. But saving energy doesn’t just mean colder spaces in the winter and uncomfortably warm spaces in the summer. As with lighting, it is generally possible to get better comfort while using less energy. HVAC systems are among the largest energy end-uses in commercial buildings. With greater energy use come greater opportunities for savings. Seven HVAC energy-saving options are:
Turning your heating and cooling off when it’s not needed is a simple way to save. Just as lighting is frequently left on when no one is around, the same happens with HVAC systems. Having someone responsible for switching off the system can work, but introduces the possibility of human error. A better option may be an automatic setback thermostat. They provide the added comfort of a pre-warmed or pre-cooled office when you arrive at work. Setback thermostats don’t cost much and automatically adjust the settings up (or down) for evenings and weekends, eliminating the uncertainty and waste of manual control. Another opportunity with HVAC systems is adjusting the temperature settings to avoid overheating or over-cooling. An adjustment of only a degree or two can cut heating or cooling bills by two to three percent. Extending that to three or four degrees can produce savings of 10 percent or more. Try making small changes to find the optimal settings that maintain comfortable conditions for employees and customers. Allowing and encouraging employees to dress comfortably and seasonably will make them appreciate the changes more.
Good equipment maintenance pays off in higher reliability of the equipment and reduced operation costs. Proper operation and maintenance (O&M) will uncover ongoing problems and eliminate nonproductive maintenance practices. Proper O&M is also important for energy performance. Aside from the obvious tasks like changing filters or calibrating controls, HVAC system maintenance can influence the energy performance of the total building. An overheating fan motor lowers the efficiency of the entire HVAC system. A leaking chiller pump will waste water, draw extra power, and also hurt the chiller efficiency.
1. Daytime air temperatures can be three to six degrees cooler in tree-shaded
neighborhoods than in treeless areas.
2. Collectively adding up the millions of small savings achieved by energy-efficiency measures such as caulking and sealing can save America two-fifths more energy than the entire domestic oil industry produces.
By adding dampers in the ducts for certain areas of your office you can control the temperature and reduce energy costs. As an example, a south facing conference room or set of offices may naturally heat up more than other rooms.
Use Energy Efficient Equipment.
Older HVAC equipment is usually not as efficient as newer products. Inexpensive HVAC equipment costs more to operate than the premium HVAC technologies. When replacing heating and cooling equipment, specify the most efficient models. Some HVAC products, such as smaller air conditioners, are rated by ENERGY STAR®. Remember that bigger is not better—oversized HVAC equipment does not run as well as correctly sized equipment. Look into heat pumps, because the latest technology is very efficient and utility companies often offer cost per Kilowatt reductions for switching from oil or natural gas to electricity. Also consider commercial/industrial grade dehumidifiers in appropriate utility or storage areas.
Office HVAC Checklist:
- Energy Audit
- Programmable Thermostats
- Heating System Tune-up
- Temperature Equalizers
- Weatherstripping and Duct Sealing
- Insulated Ducts
- Insulated Walls
- Outside Air Economizers
- Whole Building Fans
- Window Treatments
- Ceiling Fans
- Heat Pumps/ AC
- Furnace Replacement
- Air Quality by Room
- Insulated Double Walls
- Thermal Mass Floors
- Cross Ventilation
- Radiant Floors