Question

In general, where is the preferred location for providing heating or cooling within a space? That is, what might be considered an overriding principle of environmental control?


Answer 1

Your home's heating, ventilation, and air conditioning system, sometimes referred to as HVAC system, uses the majority of the energy required to operate your household. The heating and cooling system also costs more money than any other system in your home. It generally accounts for up to 50% of all your monthly utility bills.

An energy efficient HVAC system will not only help you save money and energy, but it will also contribute to your overall health and increase the level of comfort in your home. There are many different models of energy efficient home heating and cooling systems available for purchase. Obtaining sufficient information is the first step in selecting an HVAC system that works best for your household.

Centralized heating systems rely on a single piece of equipment to generate heat which is then delivered throughout the entire interior space of your home. These systems may use a variety of fuels including electricity, oil, natural gas and liquid petroleum gas.

Electrical systems do not produce any toxic by-products and are generally safe and healthy to use. On the other hand, electricity is more expensive than oil and propane. Also, in the event of a power outage, the electrical HVAC system will stop working.

With oil and propane-based systems, the equipment is able to convert most of the fuel into heat, but homeowners must have a large storage tank to hold the liquid fuel. Natural gas systems are up to 99% efficient at converting the fuel into heat; however, they require a properly functioning ventilation system to dispense the carbon monoxide gas. Oil, propane, and gas generally cost less than electricity but are not as environmentally-friendly. It is also important to remember that their price tends to be highly volatile, which makes it difficult for homeowners to budget their heating bills.

Central heating systems may include a furnace, boiler or a heat pump. A furnace uses a burning chamber and flame to convert the fuel into heat. An air handler then blows the heat through air ducts into the living space. A boiler uses fuel to heat water which is then distributed to each room through a network of pipes. Most homes in the UK use a gas boiler system for heating. Electric space heaters, pellet stoves or fireplaces can also be used for home heating. However, these systems are not very efficient and their operating costs are high.

Heat pumps are very energy efficient, as they move heat instead of producing it. They are powered by electricity and use a chemical refrigerant to transfer heat from warmer spaces to cooler spaces. In the summertime, the pump extracts heat from inside your house and delivers it to the outdoor environment, functioning like an air conditioner. This process also dehumidifies the air, with liquid water being drained into your waste water system. In the wintertime, heat is extracted from the outdoor environment and transferred into your home.

There are three types of heat pumps used in residential buildings. An air-to-air heat pump is the most common type, involving the transfer of heat from the air. Water source heat pumps extract heat from a natural supply of water on a property, while a geothermal heat pump uses a network of pipes laid 10 to 35 meters under the soil. The pipes transfer energy from the earth's crust to your home. Ductless mini split heat pumps are a modern type of heat pumps that provide zoned climate control using several interior centres. They rely on a chemical refrigerant and a fan rather than air ducts to deliver the heated or conditioned air.

Heat pumps and mini ductless split heat pumps function as both heating and cooling systems. Other home cooling alternatives include central air conditioners, window air conditioners, evaporative coolers and fans for cooling. Central air conditioners deliver consistent cooling but are costly to operate. Room air conditioners can cool one space of your house, but are bulky, loud and difficult to place into the window. Electric fans do not actually cool the air in your house but offer a wind chill effect to help you feel more comfortable. Evaporative coolers, on the other hand, cool air using evaporated water.

Energy efficient windows keep the heated or conditioned air inside and prevent thermal transfer from the outdoors. When professionally installed, these windows also insulate your home from outdoor noise and prevent condensation. Energy efficient windows have two or more panes of glass with a gas inside that helps to reduce air transfer and heat loss. Consider installing double-glazed windows. These windows feature a protective glaze on all of the panes in order to stop heat transfer and energy loss.

Improve your existing windows by adding storm windows, caulking the edges of your windows and applying weatherstripping. In the wintertime, apply an energy efficient plastic film that can be sealed using a hair dryer. Thermal drapes and fitted curtains also help insulate against thermal loss. Combine several layers of energy-saving curtains and add fitted curtains that separate the room from the window surface, creating a dead-air space that acts as an insulator.

Energy Efficient Doors, Skylights, and Conservatories

When choosing a new exterior door, inspect its energy performance rating. Doors come with an R-value to help you determine how well they insulate your home. Rather than a solid wood door, consider one with a steel skin and foam insulation core. They can be finished with a wood veneer to resemble solid wood. Doors with large windows may look nice, but are inefficient. Instead, choose one with several layers of glass and a thermal break.

Install skylights that are glazed and insulated. Professionally installed skylights prevent unwanted water leakage. If your home has a conservatory, keep the doors to the conservatory closed to avoid heat loss. Conservatories are not thermally efficient and should never be heated. Consider energy efficient glass for the conservatory or use blinds or thermal drapes to prevent heat exchange with the outdoors. Your conservatory can act as an insulating layer to the main part of your home.

To conclude, energy efficient HVAC systems, combined with energy-saving doors and windows result in significant savings. Proper maintenance and usage of your equipment prevents energy loss and prolongs your system’s lifespan. In addition, energy efficiency inevitably leads to a healthier and more comfortable lifestyle and is environmental friendly too.