SUST exam 4

The Greenhouse Effect

**process that occurs when gases in Earth's atmosphere trap the Sun's heat**. This process makes Earth much warmer

effects of a warming climate

* melting ice, higher sea levels, hotter climate
* habitat loss/ loss of biodiversity
* more frequent/extreme weather events

when do we need to get to net zero emissions?

* in order to remain below a 1.5C increase, by 2050
* below a 2.0C increase, by 2070

renewable energy and GHG emissions, from highest to lowest:

1. coal (979)
2. natural gas (477)
3. solar (44)
4. geothermal (40)
5. nuclear (12)
6. wind (11)
7. hydro (7)

levelized cost of electricity

the per unit cost of electricity, averaged over the expected life of the electricity generating facility

* solar panel: 20 years
* coal/natural gas plant: 40 years
* hydroelectric dam: 50-100 years

worry for renewable energy

* even if renewables grow at a high rate, not clear it will be fast enough
* if electricity generation is increasing with renewables- not worth it
* electrifying transportation if using bad electricity generation doesn’t help the issue

Obstacle: Market Externalities

* many of the harms caused by fossil fuels (GHG emissions) aren’t reflected in market prices
* wind, solar, etc impose lower envrio cost, but this benefit is not reflected in market prices, so it’s ignored

Obstacle: Intermittent Power

* solar and wind are intermittent sources of electricity- we can’t control when they produce
* too much/ too little power sometimes, wasteful/unreliable
* find a way to store/use the excess

Intermittent

not continuous, non dispatchable

Dispatchable

 an electrical power system, such as a power plant, that can be turned on or off; in other words they can adjust their power output supplied to the electrical grid on demand

Renewables and the Grid

using large amounts of non-dispatchable wind and solar would require some combination of:

* demand flexibility
* updated grid: long-range transmission capability
* extensive energy storage
* electricity generations other than solar/wind

Wind and Solar

* low GHG emissions, low cost
* intermittent, non-dispatchable, low (not zero) environmental harm, limited applications outside electricity

Hydro and Geothermal

* low GHG emissions, low-mid cost, constant, reliable, dispatchable
* low (not zero) enviro harm, limited growth potential, limited applications outside electricity

Natural Gas

* better than coal, very high GHG emissions (depending on methane leakage), low criteria pollutant emissions
* significant additional enviro harms (water pollution)

Energy Storage (batteries, pumped storage, etc) and Grid Updated

* necessary
* technical challenges remain, expensive

Electric Vehicles and/or Hydrogen Fuel Cells

* clear improvement over internal combustion engines
* technical challenges remain, slow transition

Carbon Capture and Sequestration

* necessity
* new technology, uncertain

Nuclear Power (obviously profs fave)

* constant, reliable, dispatchable, quick to scale, appropriate for industrial applications, etc
* U.S. has used nuclear for 65 years, caused 0 deaths (unlike deaths via pollution)

The “Answer”?

* internalize the externality
* impose tax on manufacturers equal to the marginal external cost (Pigourian Tax)

Pigourian Tax

* example: carbon tax
* this will “internalize the externality,” minimize emission abatement costs, and produce optimal results-- enable the market to do what functioning markets are supposed to do