Lab 8: Energy Resources and Efficiency — Energy Audit

1. An energy audit systematically inventories a building's energy consumption: heating, cooling, lighting, appliances, hot water, and electronics. Audits identify where energy is wasted and which upgrades offer the best return on investment.
2. Energy efficiency means accomplishing the same outcome using less energy. Example: LED bulbs provide the same light as incandescent bulbs while using 75–80% less electricity. The 'negawatt' — the watt you do not use — is the cheapest watt of all.
3. U.S. households average about 77 million BTU of energy consumption per year (EIA 2022). Heating and cooling account for roughly 48% of household energy use; water heating ~18%; appliances and electronics ~34%.
4. Phantom load (standby power): electronics consume electricity even when 'off' or in standby mode. TVs, game consoles, cable boxes, and phone chargers all draw standby power. The average U.S. household wastes 100+ kWh per year to phantom loads.
5. Energy Star ratings identify appliances meeting EPA efficiency standards. An Energy Star refrigerator uses approximately 15% less energy than the federal minimum standard. Over its lifetime, the efficiency savings offset the higher purchase price.
6. Connection to environmental impact: every kilowatt-hour (kWh) of electricity from the U.S. grid produces approximately 0.386 kg of CO₂ on average (EPA 2023). Reducing household energy use directly reduces greenhouse gas emissions.
7. Renewable energy options for households: rooftop solar (photovoltaic), solar water heating, heat pumps (replace furnaces and AC with 3–4× efficiency), and green electricity programs (purchasing RECs — Renewable Energy Certificates).
8. Connection to BIO 1120 Outcome 3: household energy choices collectively determine how much fossil fuel is burned, how much CO₂ enters the atmosphere, and — through climate change — how severely ecosystems are disrupted.

Discussion post

1. Share the single biggest energy waste you found in your home audit. What would it cost annually in electricity, and how much CO₂ does it emit?
2. Propose one realistic efficiency change your household could make (not just 'unplug everything'). What is the barrier to making that change?
3. Connect to Course Outcome 3: if every household in your zip code made your proposed change, estimate the collective impact on CO₂ emissions.
4. Reply to two classmates: compare your household's energy profile to theirs. What surprised you about the difference?

Netiquette from the syllabus: address ideas, not people. Complete sentences, correct spelling. Personal matters go to email, never the board.

Ask at home: If your family's electricity bill tripled next month, what three things would you change first — and how much do you actually think each change would save?

En español: Si la factura de electricidad de tu familia se triplicara el mes que viene, ¿qué tres cosas cambiarías primero — y cuánto crees que ahorraría realmente cada cambio?