Geology 101 Renewable Energy

Front 1

Renewable Energy Resources

Back 1

1) No one resource will provide all our energy needs
2) each has advantages and disadvantages
variety of renewable resources

Front 2

Alternative energy Advantages

Back 2

1) Renewable & abundant
2) Produce little pollution
3) low maintenance
4) Safe

Front 3

Alternative Energy Disadvantages

Back 3

1) Technology still being developed
2) Expensive
3) infrastructure compatibility
4) acceptance by society

Front 4

Solar

Back 4

Solar Farms use mirrors to focus/reflect sunlight onto a reciever

Front 5

solar electricity

Back 5

Photovoltaics
Sunlight strikes a semiconductor, knocking electrons free that flow as current
effeciently improving
2008 PV cells now 42.8% efficient
commercial cells at 14-19%

Front 6

photovoltaic

Back 6

method of generating electrical power by converting solar radiation into direct current electricity

Front 7

Solar advantages

Back 7

1) Widely available on a long timescale
Energy Payback (EPB) time it takes to generate enough energy to offset the energy used in system production
2) since 200 solar EPB has dropped 2-3 years

Front 8

Solar Disadvantages

Back 8

1) Insolation Variations
- latitude, season, time of day, weather etc
- need battery backups
2) generates DC current only
3) some pollution from making PV cells
4) room to build solar farms

Front 9

Hydroelectricity

Back 9

Flowing water used to turn turbines that generate electricity

Front 10

Hydroelectricity advantages

Back 10

1- Widely available
2- Doesn’t pollute the water
3- Quick profit
5 years to recover construction costs via sales of electricity

Front 11

Hydroelectricity Disadvantages

Back 11

1) Reservoir creating flood areas
2) Dams alter downstream environments
3) we've already used best sites
4) Fear about dam failure

Front 12

Case study: banqiao Dam

Back 12

Built to resist a 1000 yr flood event
Aug 1975: 2000 yr flood event
41in rain fell in 24hrs (full years worth of rain in 1 day)
700 million tons of H20 released in 6hrs
171,000 died

Front 13

New Buoy system

Back 13

convert kinetic energy into electricity
New Buoy system is 2 components:
1) stationary centerpiece with copper coils
2) float containing a magnet

Front 14

Buoy system advantages

Back 14

Simple device, consistent

Front 15

Buoy system Disadvantages

Back 15

1) rough Environment
storm damage/loss, salt water corrosion, marine life
2) Changes coastal environments
reduce wave energy
3)Some areas far from coasts
4) effects on wildlife
anchor line vibrations = noise pollution
Electro- magnetic fields disrupt wildlife

Front 16

Wind Power

Back 16

Winds generate 5x more power than total global energy consumption
N dakota could provide 1/3 of US electrical needs
2008 wind generates 1.5% of global electrical supply

Front 17

Wind Advantages

Back 17

1) Cost down 80% in last 20 years
2) Energy payback only 1year
3) safe for birds

Front 18

Wind Disadvantages

Back 18

1)Not consistent in many areas
2) Few places currently make the equipment
3) best sites often far from population centers
4) Not in my backyard

Front 19

WARP Turbines

Back 19

Wind Amplified Rotor Platform
More attractive tower design
focus winds into smaller area and accelerate it
faster = more energy produced

Front 20

Geothermal Advatages

Back 20

more consistent than wind, solar or hydro
provides < 1% global needs
can circulate water through pipes to draw heat
GT heat pumps: Temp below ground is more constant than at the surface
Heat water enough and you generate steam to run turbines

Front 21

Geothermal Disadvantages

Back 21

1) geothermal gradient varies
2) Fluids can contain unsafe/corrosive dissolved substances
3) Much heat energy lost during movement of fluids/steam
4) subsidence (when using groundwater)
5) can be depleted if poorly managed

Front 22

Biofuels

Back 22

Use of Bilogical materials as fuel
Renewable if managed properly

Front 23

Ethanol Advantages

Back 23

Starch from crops fermented to produce alcohol
1) mix with regular gas to reduce pollution and amount of gas needed
2) Big new source of income for farmers

Front 24

Ethanol Disadvantages

Back 24

1)Not yet cost effective without government subsidies
2) takes a lot of energy to produce
3) Ethics, growing fuel instead of food

Front 25

Algae Advantages

Back 25

Grow algae then convert their lipids into biofuel
algae farms = oil crop

1) doesn't need freshwater
2) doesn't need cropland/soil
3) waste is biodegradable
4) multiple harvests per year

Front 26

Algae disadvantages

Back 26

1) doesn't lower atmospheric CO2 levels as some claim
2) currently expensive
3) production estimates vary a lot
theory produce 150,000 gal/acre/year
reality you get 33,000 gal/acre/year