COM 106 MIDTERM -LECTURE EXAM
QUESTIONS AND ANSWERS GRADED A+
2025/2026
Waste to Energy - ANS Increasing waste from urbanization, industrialization, and lifestyle
changes harms the environment. Waste-to-energy technology converts waste to electricity and
reduces landfill use while minimizing greenhouse gas emissions.
Biomass definition - ANS Biomass is a renewable energy resource derived from carbonaceous
waste of human and natural activities, including agricultural residues, forestry waste, algae, and
organic municipal or industrial waste.
Biomass as energy - ANS Biomass substitutes fossil fuels for heating and energy generation
purposes.
Biomass and carbon cycle - ANS Burning biomass releases similar CO₂ amounts as fossil fuels,
but since biomass regrows and reabsorbs carbon, it maintains a balanced carbon cycle and does
not increase atmospheric CO₂ significantly.
Biomass examples - ANS Wood, crops, and organic waste used as renewable energy sources.
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,Fuel cells definition - ANS Fuel cells are electrochemical devices converting fuel's chemical
energy directly into electricity (DC) and heat efficiently.
Fuel cell fuel - ANS The most suitable fuel is hydrogen or hydrogen-containing compounds.
Fuel cell working principle - ANS Consists of an electrolyte between two electrodes—oxygen
passes one side, hydrogen the other—reacting electrochemically to produce electricity, water,
and heat.
Applications of fuel cells - ANS Portable military power units, auxiliary power units (e.g., for
leisure industry), and portable products such as torches or trimmers.
Merits of fuel cells - ANS Eco-friendly, noiseless, high efficiency (60-70%), compact size,
provides both electricity and heat, minimal transmission losses, and flexible fuel options
(hydrogen, methanol, etc.).
Demerits of fuel cells - ANS Technology is expensive, hydrogen production often polluting,
and hydrogen handling, storage, and refilling remain difficult.
Energy efficiency - ANS Energy sustainability requires improving both energy supply and
usage efficiency—reducing energy needed for goods and services.
Smart grid technology - ANS A smart grid uses information and communication tech to
automatically manage and optimize electricity generation, distribution, and consumption,
improving reliability, economics, and sustainability.
Sustainable design - ANS Improving building efficiency to reduce energy use in daily living and
working environments.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, Solutions for sustainable energy - ANS Improve energy efficiency, increase renewable
availability, use transitional sources (gas, nuclear), promote R&D, educate the public, and apply
fair market competition with government support.
Sustainable energy - ANS Use of energy that meets present needs without compromising
future generations' ability to meet theirs (Brundtland, 1987).
Development definition - ANS Gradual growth toward a more advanced, stronger, and
positive condition for humans and surroundings through participation in social, political, and
cultural processes.
Sustainable development origin - ANS Term introduced in the early 1970s, likely by economist
Barbara Ward, emphasizing integration of environmental, economic, and social goals.
Stockholm Declaration (1972) - ANS Contained 26 principles placing environmental issues at
the forefront and started dialogue between developed and developing nations about growth,
pollution, and human well-being.
Stockholm Action Plan - ANS Three main parts: Global Environmental Assessment
Programme, environmental management activities, and support measures for
national/international assessment—totaling 109 recommendations.
Outcome of Stockholm Declaration - ANS Led to creation of the United Nations Environment
Programme (UNEP) and the establishment of national environment ministries worldwide.
Principle 1 (Stockholm) - ANS Humans have the right to enjoy nature but must protect it for
future generations; healthy environment recognized as a fundamental right.
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
QUESTIONS AND ANSWERS GRADED A+
2025/2026
Waste to Energy - ANS Increasing waste from urbanization, industrialization, and lifestyle
changes harms the environment. Waste-to-energy technology converts waste to electricity and
reduces landfill use while minimizing greenhouse gas emissions.
Biomass definition - ANS Biomass is a renewable energy resource derived from carbonaceous
waste of human and natural activities, including agricultural residues, forestry waste, algae, and
organic municipal or industrial waste.
Biomass as energy - ANS Biomass substitutes fossil fuels for heating and energy generation
purposes.
Biomass and carbon cycle - ANS Burning biomass releases similar CO₂ amounts as fossil fuels,
but since biomass regrows and reabsorbs carbon, it maintains a balanced carbon cycle and does
not increase atmospheric CO₂ significantly.
Biomass examples - ANS Wood, crops, and organic waste used as renewable energy sources.
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,Fuel cells definition - ANS Fuel cells are electrochemical devices converting fuel's chemical
energy directly into electricity (DC) and heat efficiently.
Fuel cell fuel - ANS The most suitable fuel is hydrogen or hydrogen-containing compounds.
Fuel cell working principle - ANS Consists of an electrolyte between two electrodes—oxygen
passes one side, hydrogen the other—reacting electrochemically to produce electricity, water,
and heat.
Applications of fuel cells - ANS Portable military power units, auxiliary power units (e.g., for
leisure industry), and portable products such as torches or trimmers.
Merits of fuel cells - ANS Eco-friendly, noiseless, high efficiency (60-70%), compact size,
provides both electricity and heat, minimal transmission losses, and flexible fuel options
(hydrogen, methanol, etc.).
Demerits of fuel cells - ANS Technology is expensive, hydrogen production often polluting,
and hydrogen handling, storage, and refilling remain difficult.
Energy efficiency - ANS Energy sustainability requires improving both energy supply and
usage efficiency—reducing energy needed for goods and services.
Smart grid technology - ANS A smart grid uses information and communication tech to
automatically manage and optimize electricity generation, distribution, and consumption,
improving reliability, economics, and sustainability.
Sustainable design - ANS Improving building efficiency to reduce energy use in daily living and
working environments.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, Solutions for sustainable energy - ANS Improve energy efficiency, increase renewable
availability, use transitional sources (gas, nuclear), promote R&D, educate the public, and apply
fair market competition with government support.
Sustainable energy - ANS Use of energy that meets present needs without compromising
future generations' ability to meet theirs (Brundtland, 1987).
Development definition - ANS Gradual growth toward a more advanced, stronger, and
positive condition for humans and surroundings through participation in social, political, and
cultural processes.
Sustainable development origin - ANS Term introduced in the early 1970s, likely by economist
Barbara Ward, emphasizing integration of environmental, economic, and social goals.
Stockholm Declaration (1972) - ANS Contained 26 principles placing environmental issues at
the forefront and started dialogue between developed and developing nations about growth,
pollution, and human well-being.
Stockholm Action Plan - ANS Three main parts: Global Environmental Assessment
Programme, environmental management activities, and support measures for
national/international assessment—totaling 109 recommendations.
Outcome of Stockholm Declaration - ANS Led to creation of the United Nations Environment
Programme (UNEP) and the establishment of national environment ministries worldwide.
Principle 1 (Stockholm) - ANS Humans have the right to enjoy nature but must protect it for
future generations; healthy environment recognized as a fundamental right.
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
