According to the Urban Green Council (UGC), buildings in the U.S. account for about 48% of the overall energy and 75% of the electricity consumption in the country. The plants that produce this energy are not only bad for the environment but our health as well. When a building is poorly operated and maintained, it cost more to operate that building. But if the building is operated and maintained properly, we reduce our utility cost, the number of power plants we need, and our impact on our environment.
The Ways We Waste Energy in Your Home
Many of our homes have been built poorly and waste energy in many different ways. Some of the most common reasons our homes waste energy are:
Poorly Performing Building Envelopes: The building envelope consists of the foundation, exterior walls, roof, windows, and doors. Holes in the envelope allow excessive and uncontrolled amounts of heat and air to pass in and out of the building.
Inefficient Lighting: About 25% of the electricity used in our homes is for lighting. Needlessly high-powered over lit areas and older lamps and ballasts can waste substantial energy.
Oversized or Undersized HVAC systems: Oversized units provide too much heating and cooling, making occupants uncomfortable. Oversized units also turn on for very short periods of time, or short cycle, causing unnecessary stress to the systems leading to decreased life spans. The opposite happens to undersized systems that have to work harder than they were designed, causing them to burn out quickly.
The Building Not Being Operated as Designed: Improper operation of building systems can lead to unnecessary energy waste. For instance, if a home has an automatic lighting system and it isn’t set properly, the lights could stay on all the time, defeating the purpose of having automatic lighting.
Lack of Monitoring and Management of Plug Loads: Having large amounts of plug-in devices such as computers, televisions, and other electronics can cause our homes to use more energy than anticipated. Monitoring your plug loads can help reduce wasted energy and help meet your energy-saving goal.
Ways to Reduce Energy Demand in Your Home
Using the ways we waste energy at home as our guide. These are some of the ways you can reduce your energy demand at home. Some of these energy-saving actions require certified professional help and can be expensive to perform, while other actions can easily be done by you for under $100, and depending on where you live some of these actions can be completed for free or put money back in your pocket instantly.
High-Performance Building Envelope: The envelope of our home is the largest building system with the most impact on how much energy is used. When the envelope is properly designed and tightly constructed it prevents outside air from getting in and slows conditioned air leaking out, allowing occupants to better control indoor temperature. It also prevents moisture from getting in, preventing damage from water vapor.
There are many ways to assess the tightness of your home’s envelope. Two popular methods are Infrared photography and performing a blower door test. Infrared photography allows you to see how much heat is being lost on a cold day. Colder spots show up as blue in the photo and hotter spots show up red and yellow. The bluer the home the better the insulation, the lower the energy demand. A blower door test measures the amount of airflow through the cracks of a home to determine how leaky the envelope is, by using a powerful to suck the air out of a building. Both tests are important for determining envelope performance and are becoming more widespread.
Obviously, it is easier to create a high-performing building envelope during new construction, but it is also possible to retrofit existing buildings to improve. These retrofits are also referred to as weatherization.
Some common weatherization practices include:
- Sealing of cracks and holes in exterior walls.
- Adding insulation to the roof and exterior walls.
- Repairing or replacing drafty windows.
- Sealing air ducts to deliver conditioned air only where it is supposed to go.
Retrofitting existing structures can be a difficult process. Although some tasks you may be able to accomplish yourself, we recommend that you reach out to a home energy specialist for help. Many offer free energy assessments and you can find many of the products you need to make these upgrades here at WeWentGreen.com.
Efficient Lighting Design and Daylighting: Efficient lighting design is probably the easiest way for you to save energy and money at home and daylighting reduces our need for artificial light during daylight hours. Combining these two methods will save you significant amounts of energy and money.
- LED Lighting- LED lighting requires less energy to use than non LED lighting. They also emit less heat than standard bulbs, reducing the demand for cooling in summer. LED lighting with electronic ballasts use one-fourth the amount of energy as an incandescent.
Passive Design: Passive design takes advantage of the local climate to reduce heating and cooling loads and reduces the need for mechanical equipment to provide a comfortable temperature in your home. Passive design is easier to accomplish during new construction or heavy renovations, but some techniques can be applied to existing homes as well.
- Insulating and air sealing your home beyond common practice to minimize heat gain in the summer and heat loss in the winter.
- This is more suitable for new construction or heavy renovations. South-facing windows are a great way to warm a home during the winter, and properly positioned overhangs providing shade can reduce cooling costs in the summer.
- You should take advantage of natural ventilation when possible and use heat recovery ventilation during the heating and cooling seasons. Heat recovery ventilation systems or HRVs, allow outgoing warm air to preheat incoming fresh, cold air during the winter. During the summer incoming fresh air is precooled by the cooler outgoing air.
Proper Equipment Operations: Believe it or not you should read the operator’s manual for all the equipment in your home that has one. There is actually a lot of good information in them and when it comes to increasing the longevity and efficiency of our HVAC system, not reading it will cost you thousands. The U.S. Environmental Protection Agency (EPA) has a great maintenance checklist for you to follow that will help you prevent unwanted problems and costly repairs (HVAC Maintenance Checklist).
Your HVAC system components aren’t the only pieces of equipment that need to be maintained and operated correctly. Automatic lighting systems need to be set correctly to ensure lights don’t stay on unnecessarily. Even irrigation controllers being run improperly could lead to unnecessary waste of water and energy.
Monitor Plug Load: Simply put, anything you plug into an outlet draws electricity, even when they are turned off. The biggest offenders of causing unnecessary plug load are our mobile phone chargers, most chargers actually. A good practice to start is if it doesn’t need to be plugged in, unplug it.
There are also several energy load monitors you can add to your home that will monitor every appliance, electronic, light, etc. that uses electricity in your home. You can also have your outlets connected to a switch that will allow you to turn them on and off, helping you to prevent non-essential electronics from drawing energy when not in use.
Increase Efficiency: The easiest way to reduce your energy demand is to ensure that your building systems and appliances are energy efficient. One way to do this is to look for the energy star logo on the equipment or appliance.
- High-efficiency boilers can reduce the amount of fuel need to heat hot water or space heating by 15%. They accomplish this by capturing heat from water vapor condensing in the exhaust flue.
- Ground Source Heat Pumps (GSHPs) are one of the most efficient ways to heat and cool a building, passive design being the most efficient. GSHPs extract heat from the Earth in winter to warm a building, and dumps the heat into the Earth in the summer for cooling.
- Better controls and dedicated sensors maintain correct temperatures and turn off equipment serving unused spaces. Variable speed drives allow fans and pumps to run at the right speed, instead of all the way on or off. Take advantage of all of these features will greatly reduce energy waste and increase efficiency.
Using Renewable Energy Sources
We receive questions about solar and wind energy on a regular basis. The truth is, is that you want to take as many of the previous steps mentioned above first, before adding solar or wind. To truly take the advantages of renewable energy you need to ensure that your home is as energy efficient as possible before adding renewable energy sources to your home. By making other energy efficient improvements first, you greatly reduce the amount of solar panels, wind turbines, and batteries you need to power your home.
Solar is more popular than wind as an alternative energy source used to power our homes. Solar provides a more consistent production of power as an independent generator of energy. Sunlight shines more than the wind blows. But where the wind blows more than the sun shines, wind can be an acceptable alternative. Combining solar and wind, if it makes sense, is always the preferred method of harnessing the most out of renewable energy. But to truly maximize the freedom of using renewable energy, you need to add a way to store the energy produced.
When it comes to adding solar to your home you can have an on-grid system, an off-grid system, or a hybrid system. With an on-grid system energy is produced and used during daylight hours, off setting energy used from the national grid with energy produced by the panels on your home, at night your home would use energy from the national grid. An off-grid system has battery storage which powers your home and is not connected to the national grid. Energy is produced by solar panels or wind turbines and stored in batteries, whatever energy is needed by your home comes from your batteries. A hybrid system is connected to the national and has battery storage, providing with multiple options to power your home and reduce your energy cost at the same time.