Environmental Science Renewable Energy Systems 2

Question 1

Concentrated Solar Power (CSP) differs from photovoltaic (PV) solar in that CSP:

Accepted Answer

Uses mirrors or lenses to concentrate sunlight as heat to drive a conventional steam turbine

Answer

CSP concentrates sunlight to produce high-temperature heat used in a conventional thermodynamic power cycle (steam or Stirling engine), and can incorporate thermal storage to dispatch power after sunset.

Question 2

An offshore wind farm generally produces more electricity per unit of installed capacity than an onshore wind farm because:

Accepted Answer

Offshore wind speeds are higher and more consistent due to reduced surface friction and fewer obstructions

Answer

Oceans have low surface roughness, fewer turbulence-causing obstacles, and higher average wind speeds - improving capacity factors from ~25-40% onshore to ~40-55% offshore.

Question 3

Lithium-ion batteries are currently the dominant technology for grid-scale and electric vehicle energy storage primarily because:

Accepted Answer

They offer high energy density, long cycle life, and rapidly declining costs driven by manufacturing scale

Answer

Li-ion batteries have high gravimetric/volumetric energy density, high round-trip efficiency (~90-95%), long cycle life, and costs that have fallen ~97% since 1991 due to manufacturing scale from the consumer electronics and EV industries.

Question 4

Green hydrogen is produced through:

Accepted Answer

Electrolysis of water powered by renewable electricity, producing zero lifecycle emissions

Answer

Green hydrogen uses renewable electricity to power an electrolyzer that splits water (H2O) into hydrogen and oxygen, with no greenhouse gas emissions when the electricity comes from solar/wind.

Question 5

The primary disadvantage of biomass combustion as a renewable energy source compared to solar or wind is:

Accepted Answer

Combustion emits CO2 and air pollutants, and large-scale biomass demand can drive deforestation and land use change

Answer

While biomass is considered carbon-neutral in theory (re-growing plants reabsorbs CO2), combustion still emits particulates and NOx, and demand for biomass at scale risks deforestation, habitat loss, and food security impacts.

Environmental Science Practice Test

Environmental Science Practice Test

Environmental Science Renewable Energy Systems 2