Residential energy represents a significant portion of a community’s energy use. This includes heating and cooling your home, providing lighting, cooking and powering all your electrical devices. Energy use means resource use, which usually means coal or natural gas, which means more greenhouse gas emissions, contributing to climate change.
It probably seems daunting to try to make changes to your home, or to figure out what changes will really make a difference. Or maybe you think that reducing your energy use means reducing your comfort, or you think you’ve already done everything you can.
We’ve outlined a few suggestions below, starting with simple and relatively low-cost measures if you’re just getting started and leading up to advanced steps you can take if you want to be “Super Green!”
The Big 2
You might be thinking you just don’t have time to think about energy efficiency. We’re here to help. There are numerous steps you can take on the pathway to reducing your energy use – but we’ve narrowed all those steps down to two things that you should focus on first. Given that infiltration (air sneaking in from the outside or escaping from the inside out) can account for 30% of a home’s heating and cooling costs, we’ve identified
air sealing and
attic insulation as the primary opportunities for energy savings for Ann Arbor homeowners.
Already completed the Big 2?
The goal of air sealing is to keep conditioned air inside your home's thermal envelope. Maintaining a consistent, air-sealed barrier between the inside of your home and the outdoor weather is very important for energy efficiency and comfort. According to ENERGY STAR, sealing and insulating the "envelope" or "shell" of your home — its outer walls, ceiling, windows, doors and floors — is often the most cost-effective way to improve energy efficiency and comfort.
Think of it this way: there are enough air leaks in the typical U.S. home to equal leaving a window wide open for 24 hours a day. Simple fixes can make a huge difference: by reducing drafts you reduce the energy you’re paying for that just disappears from your house.
Sometimes it’s easy to see where the air is escaping, when you can feel cold air around windows and doors. If you’re handy with a caulking gun and sealant, there’s a lot you can do yourself. The Department of Energy’s
Tips for Sealing Air Leaks identifies many of the trouble spots for air leaks around typical homes and suggests what you can do to correct them.
But you don’t have to go it alone! A home analysis from an energy professional is a great place to start; using tools ranging from infrared cameras that detect heat loss to blower door tests that measure air infiltration, you’ll be guided through a personalized process specific to your home’s needs.
Learn more about getting a home energy analysis and working with contractors to seal up leaks in your home.
A useful tool in keeping warm air inside in the winter (and out in the summer) is insulation. The EPA
estimates that skilled homeowners or professional contractors can typically save up to 20% of heating and cooling costs (or up to 10% of total energy costs) by air sealing their homes and adding insulation in attics, floors over crawl spaces and accessible basement rim joists.
Insulation is the original low-hanging fruit. It’s relatively affordable and in most cases is easy to install or have installed, and you’ll notice a difference in your heating costs. Especially if you insulate your attic, because heat rises – always.
Later in these pages we address other places you might want to install insulation in an existing home. But the easiest place to start is your attic. Depending on the age of your home or previous home improvement projects, you may have plenty of insulation already. A
home energy analysis will not only measure existing levels of insulation in your attic but will also be able to identify where there are gaps or settling that render your existing insulation ineffective.
Want to do a quick check yourself? If you can access your attic and the floor is uncovered, take a look: can you see the floor joists? If so, you probably need more insulation. Or if you can measure it, grab a ruler; if you have less than 4 inches of insulation, you can gain a lot in terms of energy savings by upgrading your insulation.
What should I know?
Whether you’re headed to your local home supply or hardware store on your own or you’re going to call a contractor to give you an estimate on tackling this project for you, you’ll want to arm yourself with some knowledge before you start.
The Department of Energy has assembled some useful
background information on insulation where you’ll learn more about the following:
- Insulation comes in a variety of types and materials, some of which are more suitable to different parts of the home than others.
- Insulation is measured in terms of “R-value.” This number basically tells you how well insulation traps heat; the higher the R-value, the more you’re insulating your home.
- Where you live, what type of house you live in and how you heat your home are all contributing factors to how much insulation you need.
Tips to be a Pro Saver
Upgrade your home's lighting for a quick way to start saving money on your electricity bill. Replacing your remaining incandescent bulbs with compact fluorescent lamps (CFLs) can be done quickly and easily without outside help. Did you know that a CFL bulb lasts 10 times longer than an incandescent, and an LED lamp can last up to 25 times longer? Find out how much you can
save. DTE Energy has discount LEDs at several retail stores. Visit
dteenergy.com/light to view a list of retailers.
A low-flow, water-saving showerhead can save you $30/year on water heating alone! Low-flow showerheads are affordable, and you won’t have to sacrifice quality—you probably wouldn’t even recognize the difference!
Learn more about water-saving showerheads, and look for the
WaterSense logo. DTE Energy will install free low flow showerheads as a part of a free Home Energy Consultation. For more information visit dteenergy.com/HEC.
Every little bit counts – by switching to a water-saving faucet aerator, you can save $5/year on water heating. Aerators can be one of the most cost effective water conservation measures, as they are very inexpensive to replace. To learn more about water-saving faucet aerators, visit
Energy Savers. DTE Energy will install free faucet aerators as a part of a free Home Energy Consultation. For more information visit dteenergy.com/HEC.
Insulation (everything except attic)
Visit The Big 2 for detailed information on attic insulation. Insulation is a way to prevent the transfer of heat, and can help significantly lower your energy bills during the heating and cooling seasons. The thickness, density and type of insulation determine its “R-value,” which measures the insulation’s effectiveness. The higher the R-value, the more it protects against the flow of heat.
There are several different types of insulation. The most common types are fiberglass (in both batt and blown forms), cellulose, rigid foam board, and spray foam. Different types with ranging R-values are recommended for different areas of your house.
To learn more about recommended levels of insulation, visit
ENERGY STAR. DTE Energy has insulation rebates. For more information visit
High-efficiency heating and cooling systems: water heater, furnace, air conditioner
More than half of the energy used in your home likely comes from heating and cooling, which makes it an important measure to tackle if you’d like to save energy and reduce your utility bills. Upgrading your heating and cooling systems can also make your home more comfortable when the weather outside is at its worst.
If your central air conditioner is more than 12 years old, replacing it with one that is ENERGY STAR qualified can reduce your cooling costs by 30%. By switching to a more efficient model, you’ll also reduce your carbon footprint by releasing less greenhouse gas emissions into the air!
Furnaces are important here in Michigan. But did you know that your heating bill depends on the efficiency of your furnace? The average older gas or oil furnace is only 60-75% efficient, meaning that you’re losing 25-40 cents of heat for every dollar you spend.
Modern high-efficiency furnaces are 90-97% efficient. If you’re making upgrades to your heating and cooling systems, be sure to have your ducts checked and sealed to avoid any potential air leakage that might make your new furnace less efficient.
tankless whole-home gas water heater, which only heats the water when it’s needed, instead of the traditional tank-type water heater that heats water (and consumes energy) 24/7. Not only could an ENERGY STAR tankless water heater reduce water heating costs by 30%, but it also offers many other benefits.
DTE Energy has rebates for high efficiency heating and cooling systems and water heaters. For air conditioner rebates visit
dteenergy.com/ac. For furnace and boiler rebates, visit
dteenergy.com/hvacrebates. For water heating rebates visit
ENERGY STAR appliances
To earn an ENERGY STAR label, products must be significantly more energy efficient, and still deliver the performance and features that consumers demand.
By replacing your old washing machine with one that is ENERGY STAR qualified, you can reduce your energy costs by about a third (which could mean reducing your utility bill by $135). Many qualified washers use over 50% less water and have a greater capacity than regular washers, which means fewer loads of laundry.
How old is your refrigerator? If you’re stuck in the 1970s, you could be saving $200/year by switching to an
ENERGY STAR qualified model. Upgrading from a 1980s model would save you over $100/year. Due to recent improvements in insulation and compressors, ENERGY STAR qualified refrigerators use 20% less energy than those sold today without the label!
To find out more about how much your appliances could be saving you, visit
ENERGY STAR. For more information on Energy Star rebates for appliances/thermostats purchased at a store, visit
dteenergy.com/energystar. To purchase Energy Star appliances/thermostats and receive an instant rebate, visit
An exterior door represents a gap in your home’s insulated wall area. If your doors are old or not properly air sealed, they could be significantly contributing to air leakage and heat transfer. To learn more about selecting the right type of door, visit
Replace + refurbish windows
Windows account for about 10-30% of your home’s heating and cooling bill. By replacing your home’s single-pane windows with ones that are
ENERGY STAR qualified, the average Michigan home could save $372/year.
The upfront cost of replacing your windows might not always be worth the energy savings you would incur. To learn more about refurbishing your existing windows, visit
Energy Savers. DTE Energy has insulation and window rebates. For more information visit
Using your programmable thermostat to set your temperature back at night and when you’re away from home can save you a substantial amount on your heating and cooling bills. ENERGY STAR estimates that the average household could save about $180/year, just by changing your thermostat a few degrees! For tips on how to select and set your thermostat, visit
For more information on Energy Star rebates for appliances/thermostats purchased at a store, visit
dteenergy.com/energystar. To purchase Energy Star appliances/thermostats and receive an instant rebate, visit
Tips to be Super Green
Solar photovoltaic (solar PV)
Creating your own electricity using
photovoltaic (PV) technology is a great way to take your energy consumption off the grid.
Is a PV system right for you? Visit
Energy Savers to find out more.
Solar water heating
Using the sun’s rays to heat your water supply can be a very cost effective way to generate your home’s hot water. After all, sunshine is free! Read more about
solar water heaters.
Ground source heat pump (geothermal)
Geothermal technology uses the earth’s constant temperature as a heat source in the winter, and as a heat “sink” in the summer. Geothermal heat pumps use 25-50% less electricity that traditional systems for heating and cooling, and are essentially silent. A ground source heat pump can be installed in almost any home, whether new or existing, and the investment made is often recouped in only a few years by energy, operational, and maintenance savings. Read more about the many benefits of
geothermal heat pumps.
Energy recovery ventilator
In the winter, an energy recovery ventilation system reduces the cost of heating ventilated air in the winter by using the heat from warm exhaust air to heat the fresh (cold) air. The process is the opposite in the summer: the inside air is used to cool the warmer air from outside, which reduces your cooling costs. Learn about the many benefits of an
energy recovery ventilator.
ENERGY STAR roof
An ENERGY STAR qualified roof reflects more of the sun’s rays to keep your home cool in the summer. By replacing your roof with ENERGY STAR qualified products, you can lower the surface temperature by up to 100 degrees, which can reduce peak cooling demand by 10-15%. To learn more about roofs that can lower your utility bill visit