Exam 2 - Advantages and Disadvantages

Nuclear Advantages

• Low environmental impact (without accidents)

• Emits 1/6 as much CO₂ as coals

• Low risk of accidents in modern plants

Nuclear Disadvantages

• Low net energy yield

• High overall cost

• Produces long-lived, harmful radioactive wastes

• Promotes spread of nuclear weapons

Coal Advantages

• Ample supplies in many countries

• Medium to high net energy yield

• Low cost when environmental costs are included

Coal Disadvantages

• Severe land disturbance and water pollution

• Fine particle and toxic mercury emissions threaten human health

• Emits large amounts of CO₂ and other air pollutants when produced and burned

Natural Gas Advantages

• Ample supplies

• Versatile fuel

• Medium net energy yield

• Emits less CO₂ and other air pollutants than other fossil fuels when burned

Natural Gas Disadvantages

• LOW net energy yield for LNG

• Production and delivery may emit more CO₂ and CH₄ per unit of energy produced than coal

• Fracking uses and pollutes large volumes of water

• Potential groundwater pollution from fracking

Biomass Advantages

• Wildly available in some areas

• Moderate costs

• Medium net energy yield

• NO net CO₂ increase if harvested, burned, and replanted sustainability

• Plantations can help restore degraded lands

Biomass Disadvantages

• Contribution to deforestation

• Clear-cutting can cause soil erosion, water pollution, and loss of wildlife habitat

• Can open ecosystems to invasive species

• Increase CO₂ emissions if harvested and burned UNSUSTAINABLY

Geothermal Advantages

• Medium net energy yield and high efficiency at accessible sites

• Lower CO₂ emissions than fossil fuels

• Low cost at favorable sites

Geothermal Disadvantages

• High costs except at concentrates and accessible sources

• Scarcity of suitable sites

• Noise and some CO₂ emissions

Hydropower Advantages

• High net energy yield

• Large untapped potential

• Low-cost electricity

• Low emissions of CO₂ and other air pollutants in temperate areas

Hydropower Disadvantages

• Large land disturbance and displacement of people

• High CH₄ emissions from rapid biomass decay in shallow tropical reservoirs

• Disrupts downstream aquatic ecosystems

Wind Advantages

• HIGH net energy yield

• Wildey available

• Low electricity coast

• Little or no direct CO₂ and other air pollutants

• Easy to build and expand

Wind Disadvantages

• Need backup or storage system when winds die down

• Visual pollution for some people

• Low-level noise bothers some people

• Can kill birds and bats if not properly designed and located

Solar Advantages

• Little or no direct emissions of CO₂ and other air pollutants

• Easy to install move around, and expand as needed

• Competitive cost for newer cells

Solar Disadvantages

• Need access to sun

• Some designs have low net energy yield

• Need electricity storage system or backup

• Costs high for older systems but dropping rapidly

• Solar-cell power plants could disrupt desert ecosystems