Energy-efficient house model

An energy-efficient house uses less electricity, less heating, and less cooling than a standard home — without making the people inside any less comfortable. Engineers and architects design every part of the house, from the windows to the walls to the roof, with energy in mind. In this project lesson you will plan a model home that puts those ideas to work.

Where Energy Goes (and Leaks)

Most of the energy a home uses goes toward heating in winter, cooling in summer, lighting, and powering devices. A poorly designed house wastes much of that energy through drafty windows, thin walls, and old appliances. A smart design plugs those leaks before they happen.

• Heating and cooling — usually the largest share of a homes energy bill.
• Hot water — heating water for showers, dishes, and laundry.
• Lighting — bulbs that run hours each day.
• Appliances and electronics — fridges, computers, TVs, chargers.

Key Design Choices

• Orientation — face most windows toward the sun for free winter heat.
• Insulation — thick walls and roof insulation slow heat from escaping or entering.
• Double-pane windows — two panes of glass with air between trap heat.
• Solar panels — turn sunlight into electricity for the house.
• LED bulbs — give the same light as old bulbs while using far less energy.
• Shade trees — block hot summer sun, reducing the need for air conditioning.
• Thermal mass — brick or concrete walls that store heat and release it slowly.

Renewable vs Non-renewable

Where the homes electricity comes from matters as much as how much is used. Renewable sources — solar, wind, and hydro — refill themselves naturally. Non-renewable sources — coal, oil, and natural gas — run out and release pollution when burned. A solar roof lets a house make some of its own clean power.

Phantom Power

Many devices keep drawing electricity even when they look "off" — TVs, chargers, game consoles. This wasted electricity is called phantom power or vampire power. Power strips and unplugging devices when not in use cut this waste at the source.