ELG4126 Sustainable Electrical Power Systems
Final Exam – Part A
Instructions: Answer the questions in the space provided. Use no more than the space provided.
Marks for each question are as indicated.
(1)
[2 Marks] Temperatures are measured at multiple locations on the planet. Mean daily
minimum and maximum values are used to calculate the mean monthly temperature T for
each location. A baseline reference temperature Tref is calculated for each month and
location. A local temperature anomaly Tanom = T – Tref is then calculated, and the “global
temperature anomaly” is then determined by some data adjustment and averaging process.
Explain why local temperature anomalies are used in finding the global value, not
temperature itself. That is, why average the anomalies, not the temperature?
Solution:
(2)
[3 Marks] What is meant by the term “CO2–equivalent” concentration?
Solution:
(3)
[2 Marks] When used in the context of climate change detection & attribution, what is
meant by the terms (i) detection and (ii) attribution?
Solution:
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(4)
[3 Marks] A company secretly discharges hazardous waste into a water system. What is
the economic term used to describe the third party effects of such an action? Such
descriptions come in two types. Which one describes this situation and why? What is the
purpose of identifying an externality?
Solution:
(5)
[3 Marks] What purpose does the levelizing factor play in the determination of the
levelized cost of energy? Describe this by reference to, and explanation of, the three
specific variables used in finding the levelizing factor.
Solution:
(6)
[2 Marks] What is the distinguishing feature of a distributed control system?
Solution:
(7)
[2 Marks] Describe the fundamental difference between a virtual power plant (VPP) and a
distributed energy resource management system (DERMS)?
Solution:
(8)
[3 Marks] What is the central purpose of a transactive energy system, the two mechanisms
that define it, and the key operational parameter that it employs to achieve its purpose?
Solution:
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(9)
[2 Marks] Intermittency is one of the critical categories against which an emerging
renewable energy option must be assessed in order to prove its viability as a major source
of electrical power. Explain why this is so. Give explicit reference (i.e., give the name) to
an energy metric whose value is both directly and indirectly impacted by this intermittency.
Solution:
(10) [2 Marks] Consider a single p-n junction solar cell. There are three fundamental
constraints that limit the maximum cell efficiency. One of these is the bandgap effect.
Describe the bandgap effect in words, referencing the photon energy.
Solution:
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