Alternative Forms of Energy Flashcards
clean energy=
energy gained from sources that do not release air pollutants
-not necessarily green or renewable or natural
green energy=
energy derived from natural sources
- often comes from renewable energy sources
renewable energy=
power generated from sources that are constantly being replenished
clean vs green vs renewable energy
clean= no air pollutants (carbon-free/low)
green= natural sources (mostly renewable)
renewable= replenishing sources
what are 5 types of renewable energy?
- bioenergy
- wind power
- hydropower
- geothermal
- solar photovoltaics
MOST renewable energy is also “__-___”, meaning:
carbon-free (no CO2 or other greenhouse gas emissions)
T/F
not all renewable energy is C-free, and not all C-free energy is renewable
true
bioenergy is ___, but not ____
explain
renewable
not carbon-free
- we can regrow plants to burn, but burning plants releases CO2
nuclear energy is ____ (___), but _______
explain
carbon-free (clean)
non-renewable
- nuclear power plants don’t release ant GHG, but nuclear reactors use uranium that we can’t get back
wind power uses ___ to turn a set of ___ and generate ___
wind
blades
electricicy
- wind turbines are up to ___m tall, and blades can be up tp ___m long
- wind speed has to be between ___km/hr and ___km/hr for wind turbines to work
- life of a wind turbine is __-__yrs, operating continuously for ____ hours
- 200m tall, 60m long
- 13km/hr and 90km/hr
- 20-25years, 120,000hrs
what are the 4 types of turbines?
- traditional windmill (Dutch)
- land-based wind turbine
- shallow water wind turbine
- deep water wind turbine
how do shallow-water turbines stay in the water?
- deep water turbines?
shallow-water: piles are driven into the seafloor, and the turbine is placed on top of it
deep-water: the turbine rests on a floating platform, which is connected to piles that are driven into the seafloor
the world’s first floating wind farm was constructed in ____ in ___
scotland
2017
list the 5 biggest problems associated with wind power
- ideal wind sites are often in remote locations
- installation is expensive
- the wind doesn’t always blow!
- turbines= noisy and alter the landscape
- kills wildlife (esp birds)
solar power=
using solar radiation to generate electricity via photovoltaic cells; also used for heating (solar thermal)
enough energy to meet the planet’s power needs for an entire year reaches the earth from the sun in just ___
1 hour!
(we need to learn how to capture it efficiently)
T/F
an average house does not have enough roof area for the necessary amount of solar panels to supply its power needs
false
most have plenty of space!
this is how solar power capture works:
1. solar panel converts ___ to __ ____
2. _____ converts electricity DC to AC
3. you take the ___ your home needs
4. extra electricity is sent to the ___
- sunlight to DC current
- inverter
- electricity
- grid
solar ___ are used to concentrate sunlight around solar farms
mirrors
Explain the “Brooks Project” in alberta
- western Canada’s first utility-scale solar project!
- ~49,000 panels
- completed in 2022
- powering ~3,000 homes right now (90,000 in future)
Problems with solar power:
- initial ___ for installing are quite high
- ____-dependent
- ____ ____ are expensive
- requires a lot of ____
- transportation and installation of solar panels= ___ ___
- ___ materials used during manufacturing
- cost
- weather
- storage batteries
- space
- GHG emissions
- toxic
Are solar panels toxic?
short answer: no, unless we abandon them in the enviro after use
- modern panels: silicon-based (no toxic heavy metals)
- contains lots of plastic, some lead, but nothing that can leach during use
using fast-moving water to generate electricity=
hydroelectricity
water can be captured for hydroelectricity how?
-What’s the most common way?
- movement of a river (eg dams)- most common
- wave power (surface of ocean)
- tidal power (from flowing waters during the rise and fall of the tide)
what’s the leading (and oldest) form of renewable energy?
hydropower
2 main types of hydroelectric plants:
- dam
- accumulate water, regulate flow and energy
- more control - run of river
- limited storage capacity
- natural speed of the river (less control)
T/F
hydropower has zero pollutants, except construction of plants (and has a very long lifetime)
true!
a main issue with dams is they cause problems for places ____ of the dam
downstream
list 6 problems associated with water power:
- habitat alteration/ destruction
- can affect water quality/ supply (creates stagnant water)
- can displace people and wildlife
- droughts and floods- must consider when building the dam
- Construction of dams is dangerous
- safety/ maintenance over time (dam breaks= huge floods downstream)
geothermal power=
using the heat trapped inside the Earth to bring highly heated water to the surface and generate electricity
how is geothermal power captured? (list 2)
- geothermal power plants: using heat from inside the earth to generate steam (deep in the earth)
- geothermal heat pumps: using heat close to the earth’s surface to heat water or provide heat to buildings (near surface)
explain the enhanced geothermal system (EGS)
you inject water at high pressure to fracture the rocks= able to use this to heat the water then pump to the surface
where does the heat for geothermal energy come from?
sometimes the crust can crack or thin, allowing plumes of hot magma from the mantle to rise
hot water for swimming/ bathing, greenhouse heating, and aquaculture are all direct uses of ____ ___
geothermal heat
probems with geothermal power:
1. production is limited to areas near ___ ___ ___ (very limited)
2. some locations may ____ ___ over time
3. ____ and____ for new sites is expensive and high ___
4. can release harmful ___, like ___ ____
5. potential ___ due to digging and fracking
- tectonic plate boundaries
- cool down (cracks may close= no longer heated)
- drilling and exploring, risk
- gases like hydrogen sulfide (smells like rotten eggs)
- earthquakes
biomass power=
use of organic material from plants and animals
2 ways of generating biomass power:
- biological conversion of biomass (eg. anaerobic digestion by microbes)
- thermal conversion of biomass resources (eg. combustion- burn it like you would coal)
biomass can also be converted into liquid ___, such as __ and biodiesel, which is used to power vehicles
biofuels
ethanol
explain the cycle of biomass material when it’s being used for biofuel
- forests absorb CO2
- forests are harvested to produce biomass
- biomass is compressed/ stored then burned for energy (converted into heat and power)
- CO2 is released back into the atmosphere
- forests absorb CO2
list 4 biomass resources
- animal wastes
- sewage
- food processing waste
- forestry residues
note- there are unlimited sources!
problems with biomass power:
- ___ emissions
- if not controlled, can lead to ____/ destruction of habitats
- less ___ than fossil fuels/ other renewable energies
- ____ and requires a lot of ___
- unpleasant ___ and concerns about ___
- requires large amounts of ___
- GHG
- deforestation
- efficient
- expensive, space
- odors, pathogens
- water
____ is the most abundant element in the universe
hydrogen
using ____ ___, ____ energy, or ___ power, we can produce H gas store it, transport it, and ___ it to generate ___
fossil fuels
renewable energy
nuclear power
burn it
power
T/F
hydrogen emits CO2 when burned, but it yields water!
false
- does not emit CO2
- yields water vapor :)
what are some end uses for hydrogen power? what’s it similar to?
- transport
- power production/ storage
- heat for industry/ buildings
used similarly to natural gas
what are the 3 hydrogen production pathways?
- fossil resources
- coal gasification
- natural gas conversion - biomass/ waste
- H2O splitting/ electrolysis
- split water into H and O using electrolyzers
T/F
fuel cells used in hydrogen power generation need to be recharged like batteries
false!
____ ___ is the leading option right now for storing renewable energy
hydrogen production
BUT most production of H is still tied to fossil fuels
list 4 problems associated with hydrogen
- it’s expensive
- lack of H infrastructures, and not easy to convert existing ones
- still too dependent on fossil fuels to produce it (enviro impacts)
- H is highly flammable! very dangerous b/c can combust even in low concentrations in the air
