At its most basic, energy efficiency refers to a method of
reducing energy consumption by using less energy to attain the same amount of
useful output. For example, an energy-efficient 12-watt LED bulb uses 75-80%
less energy than a 60-watt traditional bulb but provides the same level of
light.
Efficient energy use has been a
rising trend due to increasing energy costs and the environmental problems
caused by greenhouse gas emissions. This green energy trend is evident in the
products and appliances for sale to consumers, many of which become more
energy-efficient from year to year. The trend also extends to homes: a growing
number of prospective homeowners are starting to request energy ratings before
deciding to purchase the property.
On a generalized scale, residential
energy consumption per housing unit has been falling over the years. This fall
in consumption is attributable to increasing energy efficiency and is
happening despite the growing number of electronic devices an average
household uses. However, the average size and the total number of housing units have
also risen over the same period. As a result, total residential energy
consumption has remained relatively constant since 1993.
In 2014, residences were responsible
for approximately 21 percent of national energy consumption, contributing an
equal amount to national emissions. There is a significant opportunity for
emissions reductions in the residential sector; in fact, the U.S. Department of
Energy estimates that you could reduce your energy use, and by extension
your utility bills, by 25-30% by implementing energy-efficient appliances and
projects in your home. Because households are charged for electricity per
kilowatt-hour (kWh), reducing your energy consumption results in proportionate
utility savings.
Energy conservation – the concept of reducing energy consumption through the
minimization of activities that consume energy – is often confused with energy
efficiency. The main difference between the two concepts is how much you have
to alter your behavior.
Energy conservation calls for a certain degree of sacrifice, such as using
the clothes dryer less often or turning down the heat in the winter. Energy
efficiency, on the other hand, maintains the same amount or quality of output
while using less energy. Instead of turning down the heat, you can install an
energy-efficient furnace to keep your house at a certain temperature while
consuming less energy than you would with a conventional one. Energy efficiency
does not inconvenience you with inhibitive restrictions, and it requires no
change in behavior on your part to reduce your utility bills.
Another misconception is that energy-efficient options are not worth buying
because they are more expensive than their conventional alternatives. Indeed,
efficient options, whether for appliances or home specifications, often come
with a high price tag. However, energy efficiency should be considered
an investment that accumulates savings over time, rather than a
typical purchase that is evaluated based on up-front costs.
The utility bill savings generated over the lifetime of an energy-efficient upgrade has the potential to offset the total purchase price and can even
generate a positive return on investment (ROI). Besides, a long-term energy-efficient installment can add value to your home upon resale.
According to the 2018 Cost vs. Value Report, an attic insulation renovation earns a 107.7% return on investment on average when you sell your house. In the Pacific region, the same investment earns over a 122.8% return upon resale. In contrast, conventional options offer lower up-front prices but require more frequent replacements and generate higher utility expenses, diminishing the benefits of saving on the sticker price.
A common misconception about energy efficiency is that replacing a couple
appliances will result in significant savings. For substantial utility savings,
you should consider a holistic approach that strategically targets the most
significant sources of energy waste in your home or business.
For example, electricity consumed by appliances that are turned off or in
standby mode, known as the “phantom load”, can add $100-$200 to your annual
utility bill. While your first instinct might be to replace appliances with a
more energy-efficient version, consider first using a smart power strip. Smart
power strips prevent plugged-in appliances from drawing power by turning off
when it senses the appliances are not in use, and effectively eliminates their
phantom load.
Another example is installing an energy-efficient furnace or air
conditioner. While installing an energy-efficient HVAC system can reduce your
energy bills, your savings will be smaller if your home is not sufficiently air
sealed or insulated because it will take more energy to maintain the interior temperature at any given level.
The price of a holistic approach to energy efficiency may seem daunting, but
keep in mind the potential savings and home
value appreciation from such upgrades. The Department of Energy estimates that
you can save about 30 percent on your annual utility expenditures through
comprehensive home improvements.
In homes and businesses, energy is used for space and water heating, air
conditioning, appliances, electronics, and lighting. However, residential and
commercial buildings are subject to separate energy efficiency standards and
regulations due to their different magnitudes of energy use.
For instance, the commercial HVAC system of an entire office building will
consume much more energy than an average home. According to the
Department of Energy, a residential building must meet the minimum requirement
of having less than three stories above ground level. Any building that is not
categorized as a residential building is considered a commercial building,
including an office building or warehouse. Energy efficiency measures will
differ in scale and price between residential and commercial buildings,
although the intended objectives are the same.