Key impacts in the environmental lifecycle of appliances include the energy and water consumed over their lifetime and hazardous releases of chemicals either at the power source or at the product's end of life. Based on data from the U.S. Department of Energy (DOE), major home appliances account for nearly one third of the nation's residential energy consumption (equivalent to about 10% of total energy consumption).
The information available to assess the energy and water impacts of different types of appliances varies by sub-category. In sub-categories like dishwashers and refrigerators, average annual energy consumption is used to characterize energy impacts. In other sub-categories, various measures of appliance efficiency are used.
GoodGuide uses the following key indicators for different appliance types:
- Room Air Conditioners — Energy Efficiency Ratio (EER) is the main indicator of energy impacts. EER is the ratio of the cooling effect measured in BTU per hour divided by electrical energy input measured in Watts. The higher the EER, the more efficient the AC unit.
- Dishwashers — kWh/year is the main indicator of energy impacts.
- Refrigerators and Freezers — kWh/year is the main indicator for energy impacts. Fridges may also have energy-intensive features such as through-the-door ice dispensers or inefficient refrigerator/freezer configurations.
- Clothes Washers — Modified Energy Factor (MEF) is the main indicator for energy impacts. MEF is an energy efficiency measure based on the energy needed to run the washer and heat the water. The higher the MEF, the more efficient the washer. Washer types are also indicative of potential energy impacts – “High Efficiency (HE)” washers use less energy than conventional, top-loading washers.
- Clothes Dryers — Energy Factor (EF) is the main indicator for energy impacts. EF is a measure of energy needed to run the dryer. The higher the EF, the more efficient the dryer. Dryers may also have energy-saving features such as moisture control/automatic shut off.
Environment scores are assigned to appliances by combining product-level environmental indicators (weighted at 75%) with company-level environmental indicators (weighted at 25%). Product-level scores incorporate the most significant aspects of the overall life cycle impacts of a product, but company-level scores are included to address product-level data gaps.
Product-level scores for appliances are based on indicators of:
- Energy use, as measured by annual energy consumption or energy efficiency metrics, appliance type, and appliance features.
- Water use, as indicated by appliance type and applicable certifications.
- Certifications of energy and water efficient appliances.
Health scores are not assigned to appliances
This product category is not associated with human health risks.
Social scores are based on company-level research.
Product-level data on societal performance are generally unavailable for this category of products, so GoodGuide relies on company-level societal scores to characterize the performance of a product on this dimension.
For each attributes selected to characterize the environmental impacts of an appliance sub-category, we applied scoring rules based upon:
Using data from EnergyGuide labels and the CA Energy Commission, GoodGuide determined the energy impact of an appliance relative to similar products. GoodGuide uses the yearly operating cost (and range for similar products) published on EnergyGuide labels to assign energy impact scores. Products with annual operating costs approaching the lower limit of the range score well, and products approaching the upper limit of the range score poorly. Clothes dryers are rated based on the Energy Factor value calculated by the CA Energy Commission. Products that exceed the minimum federal standard score higher.
Due to data availability challenges, GoodGuide is only able to indirectly assess the water use impacts of washing machines and dishwashers. Product-level data is not readily available from manufacturers on specific metrics relevant to dishwashers (e.g., gallons/cycle) or clothes washers (e.g., gallons of water used per cubic foot of capacity). Therefore, water use impacts are addressed indirectly using surrogate indicators like washing machine type or ENERGY STAR certification. High-efficiency washing machines or certified machines score higher than conventional washers.
- Combination refrigerator/freezers with top-mounted freezers use 10-25% less energy than French door, side-by-side or bottom-mounted freezer configurations.
- High-efficiency washers use 20-66% of the water and 20-50% of the energy of traditional top-loading agitator washers.
- Gas dryers are preferable to electric dryers when it comes to greenhouse gas emissions, primarily because they avoid energy transmission losses between power plants and homes.
- Fridges that have a through-the-door ice dispenser increase energy use by 14-20%.
- A dryer with a moisture sensor and an automatic shut-off feature is likely to save energy by not running longer than necessary.
On average, ENERGY STAR rated appliances perform 10-30% better than non-rated appliances on energy efficiency, and 10-50% better on water efficiency.
Note: Other Environmental Issues
Due to data availability challenges, GoodGuide ratings do not take into account the following issues that contribute to the overall lifecycle impacts of the appliance category: coolant type, foam blowing agents, recycled content, raw materials extraction and hazardous materials used in production, embodied energy, transportation, and end-of-life considerations.
In older generation air conditioners and refrigerators, coolant release to the atmosphere has been a significant component of the category's overall environmental impact. However, these issues are largely mitigated in current generation appliances:
- Room Air Conditioners — Units manufactured before 2010 may contain ozone-depleting, climate-warming hydrochlorofluorocarbon (HCFC) refrigerants which must be properly disposed of, but new units have coolant fluids that are ozone-neutral but still contribute to global warming.
- Refrigerators and Freezers — Refrigerators and freezers manufactured before 1995 typically contain chlorofluorocarbon (CFC) refrigerants, which deplete the ozone layer. Units manufactured since 1995 contain hydrofluorocarbon (HFC) refrigerants, which are ozone-neutral but are potent greenhouse gases. Units manufactured prior to 2005 may contain ozone-depleting foam, but those manufactured since 2005 contain ozone and climate neutral foam.