Alternative energy

Alternative energy

Comes from energy sources that:

• Have no undesired consequences

• Are often renewable

• Have lower carbon emissions than fossil fuels

What are alternative energy sources?

Solar, wind, hydro, other.

Wind power conversion

Kinetic to electrical energy

How does Wind power work?

• Rotating generator converts wind energy to electricity

• Increases voltage for transmission

• Input into the power grid

When/why was wind power explored?

In 1970’s as a response to an oil shortage.

• Fastest growing sector in the energy market.

• Accounts for 2% of worldwide energy.

What does it take to build a turbine?

• 335 tons of steel

• 4.7 tons of copper

• 1,200 tons of concrete

• 3 tons of aluminum

• 2 tons of Rare Earth Elements

• And more

What species does wind power affect?

Wind turbines kill ~500,000 birds annually

Who leads the world in wind energy?

Installed wind capacity in 2019:

• China: 36%

• Germany: 20%

• USA: 16%

• India: 6%

Texas and Wind power

• TX gets 21% of energy from wind – leads the USA

• Ranks 6th in the world

• Transmission is the biggest problem

Wind turbines

• Each turbine can power 600 homes

• Average lifespan of 25 years

• 25% growth each year

• Cost $3-4 Million

Pro’s of wind power

• Renewable

• operational cost

• Emissions free electricity generation

• Efficient

Con’s of wind power

• Not constant or steady

• High upfront costs

• Threat to wildlife

• Noise pollution

• Maintenance & lifespan

• etc…

Solar conversion

Photovoltaic - converts light energy into electrical energy

• Photons hit sheets of semi-conductive material, moving electrons and generating a current

Solar panels

• Average home = 14-36 solar panels

• Difficult to produce enough electricity to offset use

• Most electricity is sold to the grid to support usage

• The sun puts more energy on Earth in 1 hour than all humans use in 1 year

Solar (assisted) cars

• Doesn’t move the car

• Adds battery charge

• Increases range by 4 miles

• Solar panels only deliver a few horsepower

Solar power usage in 2018 and 2023

• China: 175.1 to 228.1

• United States: 62.1 to 132.4

• Japan: 55.9 to 82.4

• Germany: 45.9 to 72.6

• India: 27.3 to 116.1

Pro’s of solar power

• Unlimited

• Emissions free electricity

• No moving parts

• No noise

Con’s of solar power

• Only works when sun shining

• Storage

• Expensive

• Greenhouse chemicals needed for production: Nitrogen Trifluoride and Sulfur Hexafluoride

Hydroelectric conversion

Potential, kinetic, electrical

Hydro. usage

• 6.6% of US energy

• 18% of global energy

• Most abundant renewable energy

Hydro. dams

• 87,000 dams in the US: ~300 produce electricity

• The largest hydroelectric dam in the world produces more energy than 12 coal powerplants

• Mitigates historical flood damage

Pro’s of hydroelectric

• Renewable?

• No emissions

• Easily adjustable to demand

• Flood Control

• Fresh water reservoirs

Con’s of hydroelectric

• Limited viable locations

• Expensive to build

• Usually not profitable

• Damaging to ecosystems

• Dependent on water supply

• Increased evaporation

Ocean energy conversion

Ocean Thermal Energy Conversion (OTEC): Uses hot surface water and cold deep ocean water to turn a turbine

• Temperature must be 36°F different

• Limited to tropical water

Example of OTEC

MAKAI Power Station, Kauai

• Produces enough electricity to power 120 homes

• Is constant or steady

• Typically, far from populations

Tidal power conversion

Kinetic to electrical

Tidal power

• Up and down motion of the tide = tidal energy

• Requires coastline with exaggerated tidal activity

• Only two operating plants worldwide

Wave energy conversion

Kinetic to electrical

Wave energy

• Up and down motion activates a hydraulic pump

• 250-mile coastline with 3 ft waves = 1 nuclear plant

• Can generate 300x the power the world needs

Installed capacity of ocean energy

• UK: Tidal- 110, Wave- 90

• Australia: Wave- 90, Tidal- <1

• Portugal: Wave- 50

• US: Tidal- 10, Wave- 40

Pro’s of ocean energy

• Renewable

• No emissions

• Predictable

• Dispatchable?

Con’s of ocean energy

• Unknown env. impacts

• Transmission

• Expensive

• Installation & maintenance?

Biomass and Biofuels conversion

Chemical, electric, kinetic, heat.

Biomass

Uses the energy stored in plants, food and waste.

Biofuels

Sugar fermented into alcohol & converted to fuel to use for transportation.

Biomass requirements

• Tons of water and energy to grow

• Burning

Which countries use biomass?

• Brazil is the only country to profitably use biomass.

• Some African countries are 100% biomass.

How many people depend on B/B?

2.5 billion people depend on traditional biomass for cooking.

Deaths from indoor smoke from solid fuels

0-10, 50-100 in North and South America and 400-610 in Africa and Asia.

Biomass electricity in Southern states

• Are limited in wind and solar.

• Convert lumber and food waste to energy.

• Experiment in converting coal plants to bio plants.

Biofuel generation

• Requires more energy to produce than it generates

• Water use

• Pesticides

• Pumps

Pro’s of Biomass/Biofuels

• Renewable?

• Abundant?

• Carbon neutral?

Con’s of Biomass/Biofuels

• Health hazard

• Produce CO2

• Major deforestation  affects climate

• Requires large area

Geothermal conversion

Thermal, kinetic, electrical.

Geothermal

Using heat from the earth to heat or cool structures.

Geothermal process

• Hot water is pumped

• Turns into steam

• Spins a turbine

• Condenses

• Pumped back into the earth

Examples of who uses geotheral power

• <1% of New Mexico’s

• <1% of Idaho’s

• 1% of Oregon’s

• 1% of Hawaii’s

• 3% of Utah

• 22% of Nevada’s

• 72% of California’s resource

• 25% of Iceland's power

• 0.4% of US’s power

Geothermal Heat Pump

• 10ft below the surface

• Temperature is constant ~74%

• Cool in the summer and hot in the winter

• 72% less energy than an electric system

• 2-10 year cost recovery

Pro’s of geothermal

• Little pollution

• Renewable

• Scaled up or down

• Meets baseload demand

Con’s of geothermal

• Small EQ

• Minor subsidence

• Location specific

• Expensive?

Nuclear conversion

Chemical, kinetic, electric

What is nuclear?

Fission = Splitting of Uranium atom to produce heat

• Only nonpolluting energy source that can produce electricity 24/7.

• ~8% US electricity.

Most reliant countries on nuclear energy (FUSH)

• France: 76.3

• Ukraine: 56.5

• Slovakia: 55.9

• Hungary: 52.7

Nuclear waste

• Radioactive waste material from the use of nuclear fuel.

• Emits radiation

• Cannot be disposed of with regular waste

• 1 in 3 Americans lives within 50 miles of nuclear waste

Cooling tanks

• Requires 5x as much material

• Relies on electricity to run

• Vulnerable to accidents/attacks

Dry casks

• Steel and concrete

• Air Cooled

• No electricity

Yucca Mountain, NV

• Long term, underground storage facility

• Defunded in 2011/2018 under the Obama and trump administration

• Costs as high as $100 Billion

Andrews, TX

• Costs $10,000 per cubic foot

• Texas wants to ban high level fuel rods

• Companies lobby for high level fuel rods

Accidents- Chernobyl

Emergency backup test gone wrong

• ~$700 Billion

Three Mile Island

Computer error stopped water from going to steam generators

• ~$5 Billion

Fukushima-Daiichi

Safeguards were damaged during earthquake and tsunami

• ~$187 Billion

Energy density (Mj/Kilo) (w,s,c,f,g,ng,h,n)

• Wood- 16

• Sugar- 17

• Coal- 25

• Fat (from surgery)- 38

• Gasoline- 46

• Natural gas- 55

• Hydrogen- 120

• Nuclear- 80,000,000

Pro’s in nuclear

• Extremely energy dense

• Cheap to run

• Great base load provider

• Low emissions

• Sustainable?

Con’s of nuclear

• Mining of Uranium

• Expensive to build

• Potential accidents

• Nuclear waste

Why not alternative?

GHG (Emissions (Tones CO2e/GWh) Lignite, Coal, Oil, and Natural gas are high.

Why not alternative?

• Dispatchability

• Storage

• Transmission

• Scalability

• $$$$

Storage Problem

• Must generate electricity in real time!!

• What to do with extra electricity that is generated??

• Gigantic Batteries?

• 4 Hours of power to 60,000 homes

• Costs ~$2 Billion

Why not Alternative?

• “ We can’t drill our way out, we can’t conserve our way out, we can’t bomb our way out… we need to do it the old fashioned American way… we need to invent our way out…together”

• Donald Sadoway,

• MIT Professor of Materials Chemistry

Thermal Storage

• Cheap

• Abundant

• Domestic

Transmission

• Lose ~7% of power during transmission

The Duck Curve

The growing challenge of balancing solar energy with real-time demand.