A household replaces incandescent bulbs with LEDs that provide the same light using less electricity. Is this energy efficiency or energy conservation?

A student takes shorter showers, reducing the amount of hot water used. Is this energy efficiency or energy conservation?

Weatherstripping is added so a classroom stays at the same temperature while its heater runs less. Is this energy efficiency or energy conservation?

A family turns off a game console rather than leaving it in use when no one is playing. Is this energy efficiency or energy conservation?

An old refrigerator is replaced with a model that keeps food equally cold while using fewer kilowatt-hours. Is this energy efficiency or energy conservation?

Instead of driving separately, three classmates ride together in one car for the same trip. Is this energy efficiency or energy conservation?

A factory installs a motor that performs the same pumping work while drawing less electricity. Is this energy efficiency or energy conservation?

An office policy requires employees to switch off lights in empty rooms. Is this energy efficiency or energy conservation?

An audit finds 40% of a home's heat loss through an attic and 6% through one window. Attic insulation costs $1,800, and window replacement costs $1,200. Which measure cuts more heat loss per dollar?

Measure A saves 500 kWh per year and costs $250. Measure B saves 300 kWh per year and costs $100. Which saves more electricity per dollar of upfront cost?

A programmable thermostat saves 300 kWh per year for $150. Weatherstripping saves 180 kWh per year for $60. Which saves more electricity per dollar spent?

A high-efficiency washer saves 240 kWh per year and costs $400 more than a standard model. An efficient dishwasher saves 180 kWh per year and costs $150 more. Which has the greater annual kWh saving per extra dollar?

Window film reduces annual cooling use by 180 kWh and costs $300. Shade trees reduce it by 120 kWh and cost $100. Which measure saves more cooling energy per dollar?

Repairing a steam leak saves 900 GJ per year and costs $3,000. Installing a variable-frequency drive saves 600 GJ per year and costs $1,000. Which saves more energy per dollar?

Route planning saves a delivery fleet 400 L of fuel per year for $200. Low-resistance tires save 600 L per year for $600. Which saves more fuel per dollar?

An automatic shutdown schedule saves 80 kWh per month, while an LED retrofit saves 1,000 kWh per year. Which has the larger annual electricity saving?

A 60-W lamp is replaced by a 10-W LED used 4 hours per day for 5 days. How much electricity is saved?

A 500-W appliance is replaced by a 300-W model that runs 6 hours per day for 10 days. How much electricity is saved?

An efficiency upgrade costs $600 and lowers an electricity bill by $150 each year. What is its simple payback period?

A school pays $900 for efficient equipment that saves $225 each year. What is the simple payback period?

Insulation lowers a building's monthly electricity use from 1,000 kWh to 700 kWh. At $0.20 per kWh, how much does it save each month?

A 2-kW pump runs 5 hours per day. A controller reduces operation to 3 hours per day for 10 days. How much electricity is saved?

A retrofit costs $1,200 and reduces use from 2,000 to 1,400 kWh per year. Electricity costs $0.15 per kWh. What is the simple payback period?

Twenty 100-W lamps are replaced by 40-W lamps and operate 6 hours per day for 10 days. How much electricity is saved over the 10 days?

A hospital generator produces electricity, and its normally wasted heat warms nearby buildings. What practice is this?

A hybrid vehicle uses its electric motor as a generator during braking and stores the captured energy in a battery. What is this process called?

A factory pump does not need full flow all day, so its motor speed is electronically adjusted to match demand. Which efficiency technology is being used?

A gas-turbine plant sends its hot exhaust through a unit that boils water to drive a second turbine. What is this unit called?

A delivery driver turns off the engine during a 15-minute loading stop instead of leaving it running. What transport energy-saving practice is this?

A hybrid car's gasoline engine turns itself off at a red light and comes back on when the driver presses the gas pedal. Which feature reduces fuel use while the car is stopped?