An Alliance to Help Illinois Residents Lower Their Energy Costs

Close your blinds during summer days

  • Cost: Free
  • Yearly Savings: $15-35 ?

    How are savings calculated?

    Yearly savings are estimated for a standard home in the Chicago area with the characteristics you select above. We estimate savings based on government data, local weather patterns, energy prices, and scientific papers. Your actual savings will depend on your home, behavioral patterns and equipment.

    If you're interested in more details, read on!

    We disaggregate energy use for each house type into space heating, water heating, cooling, and appliance end uses using the method developed by the U.S. Department of Energy for the Residential Energy Consumption Survey (RECS), and these disaggregations serve as inputs into the calculations. Calculations are based on engineering models taken from numerous sources including peer reviewed publications, National Institute of Standards and Technology (NIST) handbooks and reference materials, the Environmental Protection Agency's (EPA) Energy Star Program, various utility technical resource manuals, and other similar sources. Additional sources of data include secondary housing characteristics data at the zip-code level from the U.S. Census, hourly weather data from the National Climate Data Center, and incoming solar radiation data from the National Renewable Energy Laboratory.

    Dollar savings from actions are calculated based on the latest available monthly electricity price for ComEd. Natural gas, propane, and fuel oil prices are taken from latest statewide monthly average price data from the EIA. State-specific tap water prices (per gallon) are taken from the 2006 Water & Wastewater Rate Survey.

    We determine carbon emissions from electricity use based on North American Electricity Reliability Corporation (NERC) subregion level emission factors based on fuel mix and generation efficiency data from the EPA's eGRID. Emission factors also include state-level average transmission losses based on data from the Energy Information Agency (EIA) and indirect emissions associated with the fuel-cycle, plant construction, and plant decommissioning of natural gas, nuclear, oil, coal, solar, wind, biomass, geothermal, and hydro power based on P.J. Meier's "Life-Cycle Assessment of Electricity Generation Systems and Applications for Climate Change Policy Analysis" (2003). Direct emissions from natural gas, fuel oil, propane, gasoline, and diesel use are calculated based on standard emission factors from the EPA and estimated fuel-cycle emissions from Meier (2003).

  • Carbon Reduction:3185-7432 lbs CO₂ ?

    What do these tree icons mean?

    The number of trees represent how much less carbon dioxide (CO2) your home energy usage will introduce into the environment if you take the corresponding energy-saving action. Or, put another way, they tell you about how much you can reduce your carbon footprint by taking each action. One tree signifies a small CO2 reduction. Two trees signifies a medium-sized reduction. Three trees signifies a large reduction.

    If you're interested in how we chose the 1-3 tree scheme, read on!

    • 1 tree: Actions that reduce up to 400 lbs. of CO2 annually. These actions tend to be behavioral in nature, or if they rely on techonology, it's simple technology: for example, closing your blinds during sunny summer days, and putting an insulating wrap on your water heater.
    • 2 trees: Actions that reduce between 400-1000 lbs. of CO2 annually. These tend to be actions that rely on using efficient devices that are generally easy to find and install, for example, low-flow showerheads and CFL bulbs.
    • 3 trees: Actions that reduce more than 1000 lbs. of CO2 annually. Generally these are actions that involve upgrading key heating, cooling or insulation systems, for example, installing an efficient furnace or central A/C system. For many such actions, most people will want to have a professional contractor perform the installation. It's also these high-effort, high-impact actions that most frequently have incentives to make follow through easy and affordable.

    What carbon means to you and me...

    • 1 car off the road = 11,133 lbs CO2 per year
    • 1 mile driven = 0.9 lbs CO2
    • 1 100w lightbulb = 170 lbs CO2 per year
    • 1 100w lightbulb for 1 hour = 0.16 lbs CO2
    • 1 barrel of oil = 948 lbs CO2

    Click here to learn more about the science of climate change.


  • save 10% - 15% on your summer cooling costs.
  • enjoy a cooler home during hot summer days

Cooling your home during the summer takes a lot of energy. You can help keep your home cool by limiting the amount of sunlight that enters if you just shut the blinds during the day. You should especially consider your south and west facing windows because they recieve the most direct sunlight. 

Sunlight carries a large amount of heat, as anyone who has ever had a sunburn can readily attest, and windows are the single largest heat inflow for most houses during summer days. Close your blinds when the sun is up to prevent heat from entering your home, and open them again when the sun goes down to help any extra heat escape.