Chapter 18: Energy Policy and the Environment Flashcards
What are energy systems?
Energy Systems present major environmental challenges:
- Heat and power
- Transport
What are CT Options ⇒ I. Heat and Power Options & II. Transport Options
What are Heat and Power Options (1)?
Heat and Power
> Energy Efficiency: Often the cheapest way to meet system power needs
- Coal (27%)
- Nuclear (19%)
- Natural Gas (35%)
- Renewables (10%) [wind, solar, geothermal, biofuels]
- Hydroelectric Power (7%)
What is demand-side management?
Demand-Side Management: (DSM) Promote technologies use energy more efficiently (or at most efficient times of the day)
“Produce” energy by freeing up supply:
- Weatherization
- Cogeneration
- Energy efficient lighting, industrial motors and cooling and cleaning appliances
- Peak shifting
Most efficient time of the day: not use energy during peak time
- Reduce need new time
Heat and Power
Coal
- Decreased energy consumption from 48%-27%
- Common poorer countriesWhy?(1) competition from natural gas and renewables;(2) aging plants facing new environmental regulations;(3) fear of future CO2
Heat and Power
What are the historical advantages and problems with coal?
-
Historical advantage:
- relaible, low-priced fuel - cheap and easy to mine
- well-developing tech
- abundance domestic resources
-
Problems:
- Primary source global pollution
- Criteria air pollutant (plus mercury)
- Acid rain
- Mining pollution and occuptational illness
- impact transport on roads
Heat and Power
What is Nuclear Economics?
- 110 in US; only few new ones since mid-1970s
Is it cost-competitive? Is it clean? Is it “safe?
Nuclear Economics:
- Expensive: ~$10 billion produce plant (but cheap to run)
- High upfront cost but cheap marginal cost
- Must access government funds
- Therefore, underbuild safe num plants
- Government not willing spend money
- Two new reactors under construction:
- Subsidize with:
- Loan guarentees
- Caps on accient damage liability
Tech risk: What if solar power rends more uneconomical? then big loss
Heat and Power
Environmental Impacts of Nuclear Power:
Benefits:
- Low carbon source power (+)
- Low air pollution (+)
Costs:
- Radiation release and meltdowns {Chernobyl, Fukishima) (-)
- Waste disposal (-)
- Uranium mining impacts (-)
Heat and Power
Waste disposal for nuclear power:
High-level Waste:
- Toxic hundreds thousands years
- Spent fuel rods
- Waste from weapons production
Storage:
- Burial geologically stable formations or underground
- Above-ground storage in pools on site in current situation
- Lots concrete required & increase risk terrorism
Political oppotions of sitting in largely halted nuclear power
Low-level Waste:
- Toxic for decades
- Contaminted clothing
- Medical and pharmaceutical waste
What are the challenges for nuclear power?
High centralized tech(in a words moving towards distributing, small scale (lower risk), decentralized energy production)
- China: only country building lots new plants → drive tech advances - could make competitive
Where to locate plant?
Heat and Power
Natural Gas
Increase 20% to 35% energy share
Cleanest fossil fuel?
- Cleaner coal - terms criteria pollutants
- Yields 70% more energy each unit CO2
But,
(1)“fugitive emissions” of methane at drilling sights
(2) Fracking controversy: local water quality and other impacts (clean but unsafe)
(3) Natural gas hydrates: losts in the artic - hard to acess and not safety protected
Heat and Power
Hydroelectric Power
7% nation’s energy mix
- Half nation’s potential hydro sites been developed
- Dam projects have significant environmental impacts:
- Glooding ecologically valuable lands
- Negative impacts aquatic life
- Methane from flooded lands
Heat and Power
Active vs. Passive Solar
Active Solar:
- Photovoltaic Power: produces electricity directly from solar cells
- Solar thermal Power: focuses sun’s energy to heat liquid and drive stream turbine
Passive Solar:
- Produces heat: mostly used heat houses and pre-heating water
Heat and Power
Solar Economics:
- PV Panels seen rapid cost declines last decade ⇒ crossed threshhold from early-stage clean technology
- Utility scale solar PV and utility scale solar thermal → cost-competitive many parts of the world.
Rooftop (distrubtion) still expensive - cheaper fast
Issue: Intermitency
- What do you do at night?
Heat and Power
Wind Power
Grow rate ~20% year
- Cost competitive
- Major environment impact is noise and aesthetics (Bat issues but not birds anymore)
- Similar problem: Intermitency
Type: On-shore and off-shore
a. On-shore
1. Ugly
2. Loud
b. Off-shore:
Places greatest wind-potential → where tourists go
Heat and Power
Geothermal
Commercial scale: large amounts at little costs