SJSU ENVS 119 Final Study Guide
questions and answers a+
How is the potential wind power output calculated for a specific site and turbine?
(Formula)✔✔P=0.5 x p x Cp x v^3 x As
p= 1.2kg/m^3
Cp= energy coefficient (.4-.5)
v^3= meters per second (double wind speeds=8 fold in power)
As=m^2 (area swept by blade)
How can the social gap in renewable energy be overcome?✔✔Include more people
in the conversation and what could be the benefit.
Define « intermittent » for wind energy. Why is it a problem?✔✔Wind energy can be
on/off depending on the weather.
Primary source of power for wind energy?✔✔Solar energy
Due to uneven heating of Earths surface
Define payback time for average project in Wind energy.✔✔he amount of time it
would take to save enough money in operation costs to pay for the equipment
How much of CA electricity is likely to be produced from Wind by 2050.✔✔35%
Passive home design✔✔a system of putting the sun's energy to use without
requiring mechanical devices to distribute the collected heat
Insolation✔✔the delivery rate of solar radiation per unit of horizontal surface
Insulation✔✔A substance that reduces the transfer of thermal energy.
Solar Path✔✔refers to orientation of building so that the sun passes and heats the
house
HDD✔✔Correlation on temp. outside vs. temp. inside
How do photovoltaics generate electricity?✔✔a method of converting sunlight to
electricity using layers of materials that either readily give up or absorb electrons
Define: Solar Photovoltaic (PV)✔✔a power system designed to supply usable solar
power by means of photovoltaics
Define: Solar Thermal Energy✔✔energy produced by converting solar energy into
electrical energy through the use of mirrors
, Understand efficiency factor, what is the normal efficiency from PV panels?✔✔Most
typical silicon solar cells have a maximum efficiency of around 15-22%.
Understand energy intermittency of Solar and why energy storage is
needed.✔✔solar radiation is zero at night, and affected by cloud cover and air
turbidity during the day.in order that it not be wasted, as well as offering back-up
power in scenarios where renewables are used in some way.
What is EROI and how do you calculate it?✔✔Energy Return on Investment (EROI)
is the amount of energy that has to be expended in order to produce a certain
amount of energy.EROI = Energy Output / Energy Input
EPBT✔✔Energy Pay Back Time
Why are a majority of renewable energy projects are now able to compete with fossil
fuels on the market place, even without subsidies?✔✔the unsubsidized cost of solar
and wind power has already reached parity with conventional fossil fuels in many
parts of the United States.
LCA Category✔✔Life-Cycle Assessment: a technique to assess environmental
impacts associated with all the stages of a product's life from raw material extraction
through materials processing, manufacture, distribution, use, repair and
maintenance, and disposal or recycling
system boundaries✔✔the border between a system and the rest of the environment
functional unit✔✔a quantified description of the performance requirements that the
product system fulfills
Define 1st Generation biofuels✔✔refer to the fuels that have been derived from
sources like starch, sugar, animal fats and vegetable oil. The oil is obtained using the
conventional techniques of production. (firewood)
Define 2nd Generation biofuels✔✔also known as advanced biofuels, are fuels that
can be manufactured from various types of non-food biomass. Biomass in this
context means plant materials and animal waste used especially as a source of fuel.
Define 3rd Generation biofuels✔✔refers to biofuel derived from algae. Previously,
algae were lumped in with second generation biofuels.
What are the options to produce a biofuel version of Diesel?✔✔Biodiesel refers to a
vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl (methyl,
ethyl, or propyl) esters. Biodiesel is typically made by chemically reacting lipids (e.g.,
vegetable oil, soybean oil, animal fat with an alcohol producing fatty acid esters
What are the options to produce a biofuel version of Gasoline (ie: Ethanol)✔✔Most
ethanol in the United States is produced from starch-based crops by dry- or wet-mill
processing
questions and answers a+
How is the potential wind power output calculated for a specific site and turbine?
(Formula)✔✔P=0.5 x p x Cp x v^3 x As
p= 1.2kg/m^3
Cp= energy coefficient (.4-.5)
v^3= meters per second (double wind speeds=8 fold in power)
As=m^2 (area swept by blade)
How can the social gap in renewable energy be overcome?✔✔Include more people
in the conversation and what could be the benefit.
Define « intermittent » for wind energy. Why is it a problem?✔✔Wind energy can be
on/off depending on the weather.
Primary source of power for wind energy?✔✔Solar energy
Due to uneven heating of Earths surface
Define payback time for average project in Wind energy.✔✔he amount of time it
would take to save enough money in operation costs to pay for the equipment
How much of CA electricity is likely to be produced from Wind by 2050.✔✔35%
Passive home design✔✔a system of putting the sun's energy to use without
requiring mechanical devices to distribute the collected heat
Insolation✔✔the delivery rate of solar radiation per unit of horizontal surface
Insulation✔✔A substance that reduces the transfer of thermal energy.
Solar Path✔✔refers to orientation of building so that the sun passes and heats the
house
HDD✔✔Correlation on temp. outside vs. temp. inside
How do photovoltaics generate electricity?✔✔a method of converting sunlight to
electricity using layers of materials that either readily give up or absorb electrons
Define: Solar Photovoltaic (PV)✔✔a power system designed to supply usable solar
power by means of photovoltaics
Define: Solar Thermal Energy✔✔energy produced by converting solar energy into
electrical energy through the use of mirrors
, Understand efficiency factor, what is the normal efficiency from PV panels?✔✔Most
typical silicon solar cells have a maximum efficiency of around 15-22%.
Understand energy intermittency of Solar and why energy storage is
needed.✔✔solar radiation is zero at night, and affected by cloud cover and air
turbidity during the day.in order that it not be wasted, as well as offering back-up
power in scenarios where renewables are used in some way.
What is EROI and how do you calculate it?✔✔Energy Return on Investment (EROI)
is the amount of energy that has to be expended in order to produce a certain
amount of energy.EROI = Energy Output / Energy Input
EPBT✔✔Energy Pay Back Time
Why are a majority of renewable energy projects are now able to compete with fossil
fuels on the market place, even without subsidies?✔✔the unsubsidized cost of solar
and wind power has already reached parity with conventional fossil fuels in many
parts of the United States.
LCA Category✔✔Life-Cycle Assessment: a technique to assess environmental
impacts associated with all the stages of a product's life from raw material extraction
through materials processing, manufacture, distribution, use, repair and
maintenance, and disposal or recycling
system boundaries✔✔the border between a system and the rest of the environment
functional unit✔✔a quantified description of the performance requirements that the
product system fulfills
Define 1st Generation biofuels✔✔refer to the fuels that have been derived from
sources like starch, sugar, animal fats and vegetable oil. The oil is obtained using the
conventional techniques of production. (firewood)
Define 2nd Generation biofuels✔✔also known as advanced biofuels, are fuels that
can be manufactured from various types of non-food biomass. Biomass in this
context means plant materials and animal waste used especially as a source of fuel.
Define 3rd Generation biofuels✔✔refers to biofuel derived from algae. Previously,
algae were lumped in with second generation biofuels.
What are the options to produce a biofuel version of Diesel?✔✔Biodiesel refers to a
vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl (methyl,
ethyl, or propyl) esters. Biodiesel is typically made by chemically reacting lipids (e.g.,
vegetable oil, soybean oil, animal fat with an alcohol producing fatty acid esters
What are the options to produce a biofuel version of Gasoline (ie: Ethanol)✔✔Most
ethanol in the United States is produced from starch-based crops by dry- or wet-mill
processing
