Midterm Exam Calculations

Potential Energy

mass x gravity x height

power (w)

energy (J) / time (s)

Sustainability

Meeting the needs of the present without compromising the ability of future generations to meet their own needs.

Renewable Energy

Energy derived from natural resources that are replenished naturally over time

Non-renewable Energy

Energy derived from finite resources that will eventually run out

Energy

The capacity to do work.

Kinetic Energy

Energy of motion

potential energy

Stored energy due to position or state

Embodied Energy

The total energy required to produce a product, including raw material extraction, manufacturing, transportation, and disposal.

Fuel Efficiency

A measure of how much energy is converted to useful work.

1 kWh to J

3.6×10⁶ J

1 kW

1000 W

1 MW

1 × 10⁶ W

1 GW

1 × 10⁹ W

Energy (KWh)

power (kW) x Time (hours)

fossil fuels

provide 60% of global electricity

hydropower

provides 15% of global electricity

wind and solar

together provide 10% of global electricity

nuclear

provides 10% of global electricity

an average coal power plant produces

500 to 2,000 MW

an average natural gas power plant produces

250 MW to 1,000 MW

an average nuclear power plant produces

500 MW to 1,500 MW

an average hydropower plant produces

several hundred MW

an average onshore wind turbine produces

2 to 5 MW

an average offshore wind turbine produces

8 to 15 MW

an average photovoltaic solar farm produces

hundreds of MW

an average geothermal power plant produces

a few MW to around 100 MW

an average biomass power plant produces

10 MW to 50 MW

energy gap

the risk that the electricity demand will sometimes exceed the supply if adequate plans are not implemented

life cycle analysis

what does the lifespan of a technology product look like, what happens when it can no longer be used

24kWh

1kW = 1000W

LED’s

more efficient than fluorescent bulbs with a longer lifespan

second-hand energy

wind power

third-hand energy

wave power

hotspots

areas with high geothermal activity

peak oil

the point when global oil production reaches its maximum rate, after which it will begin to decline irreversibly.

entropy

a measure of the quality of energy

toe

tonnes of oil equivalent

density of water

1000kg/m^³

1 litre of water weighs

1kg

half life

The time taken for the radioactivity of a specified isotope to fall to half its original value.

atom used in nuclear fission

U (uranium) - 235

WEC’s

wave energy converters