Planning for Energy Usage
Second Team Assignment
In class presentations on Monday Feb 11
In the wake of the California Energy Crisis, the City of Eugene has
decided to invest in its own power generating facilities, possibily
based on renewable energy, to power the city and its residential
customers for the next 30 years.
The present peak power requirements of Eugene is 500 Megawatts (MW)
with an average load of about 300 MW. There are 60,000 paying
customers currently in Eugene. Approximately 1/3 of these are
commercial customers which can be charged (either higher or lower)
a different rate than residential customers.
Your goal is to outline an energy plan, based on the following
alternatives (you could pick one, or you could pick several
and mix and match) that will provide sustainable power at an affordable
price to the citizens of Eugene. Whatever capital costs that you
incur in building a facility should be amortized over 30 years (
the life of this contract). You may model energy conservation
if you like in some reasonable way. In round numbers, the typical
Eugene home today, assuming that heating is done by electrical
means (baseboard, ceiling cable) requires 2KW of power averaged
over the year.
In your report you should focus on 4 things, with the third thing
occupying most of your time:
- The projected population for the year 2030 in Eugene and
the projected number of residential versus commercial customers -
state your assumptions
- The projected averge and peak power needs by the year 2030 in Eugene -
state your assumptions - you may factor in energy conservation
somehow or you may increase energy per household due to increased
- Give your energy plan based on the set of alternative
choices listed below
- Calculate the approximate price per KWH that the residential
customer will have to pay the city of Eugene over this time
period. Remember, you want to at least break even after 30 years.
You are allowed to do what EWEB is currently doing in its tiered
pricing structure the more you use, the
more you pay.
If you want to make a profit and use that money to build better
schools, etc; then you can factor this in!
Note: This assignment is intensive, you should have each
member of your group assigned a specific task in order to properly
evaluate all the alternatives
You may choose from the following list of energy sources and
mechanisms of energy storage. It is very important
that you build energy storage capacity into your system (if
that is needed).
Choose one or more of the Following Energy Sources:
- 1. Solar PV Arrays (needs storage)
- 2 .Magic Hydro Power that doesn't kill salmon (does not need storage)
- 3. Wind Power (needs storage)
- 4. Environmentally Friendly Coal Burning (doesn't need storage)
- 5. Biomass Burning (doesn't need storage)
Choose of the of the Following means of Energy Storage:
- Hydrogen burning
Each storage facility that I describe below has a capacity of
200 Megawatts but variable durations over which that power can
You need to realistically calculate the capital costs of
building the facility, how much land it will utilize, and what
the operating costs are. I will give you all the relevant
numbers for this.
The way efficiency works is as follows:
If I have some energy storage system which is only 10% efficient,
then that means I have to deliver 2000 Megawatts of energy to that system
in order to store 200 Megawatts. In this case, since 500 Megawatts
was the original goal, I would have to build 4 more 500 Megawatt units
just to have energy storage. Obviously this is silly, but the point
is that you must factor this in.
Specifications for 200 MegaWatt Storage Facilities
1. Hydrogen: Efficiency = 25%. Energy storage = 40 kilowatt hours per
gram. Hydrogen is separated from water via electrolysis and when
burned recombines with oxygen to form water. Approximately 10%
of the mass of water is in the form of hydrogen. A 10,000 liter
facility (about 2500 gallons) that stores the hydrogen in cryogenic
form, costs 2 million dollars to build and 0.5 cents per KWH to
operate. Each 10,000 liter facility can produce energy for a period
of 8 hours. The facility can be recharged in another 8 hour period.
Sodium-Sulfate Batteries: Efficinecy = 50%. Energy storage = 100
Watt hours per kilogram. Battery life is 72 hours. Charging period
is 12 hours. The batteries cost 10 dollars per kilogram to manufacture.
The operating costs for a 200 Megawatt facility are 1 cent per KWH.
Fused-Silica Flywheels: Each flywheel has a mass of 600 kg and
a radius of 100 centimeters. Efficiency = 80%. Energy storage capacity
per flywheel is 500 Watt hours. Each flywheel costs $10,000 to
manufacture. Each flywheel can deliver energy continuously for 30 days
before it needs to be recharged. The recharge period is 72 hours per
A 200 Megawatt facility would have an operating cost of 0.1 cents per
Specifications for the Energy Generating Plant:
1. Solar PV Facility:
- Location: Eastern Oregon
- Incident solar radiation: 1000 Watts per sq. meter in summer
and 300 Watts per sq. meter in winter
- Efficiency: 10%
- Panels cost 150$ per sq. meter to make
- Failure rate is 5% per year (1 out of 20 panels fails each
- Operating costs are expected to be 0.1 cents per KWH
2. Salmon Friendly Hydro Power:
- Location: New dam on columbia river
- Efficiency of turbines: 90%
- Height of spillway: 10 meters
- 4 thousand gallons per second of flow generates 1.5 MW of power
- Dam costs $2,000 per gallon per second of flow
- Friendly fish navigation devices $2,000 per gallon per
second to build
- Operating costs are 0.75 cents per KWH (0.25 of it for
3. Wind Power:
- Location: Headlands of Oregon Coast
- Average wind speed = 10 miles per hour
- Power generated by this wind = 250 Watts per square meter
- Power goes as the cube of the wind velocity. Assume 50
days per year when the average wind speeed is 30 miles per hour.
- Windmill manufacturing costs are 500 dollars per square meter.
- There are no operating costs
- Failure rate of windmills is 1% per year
4. Coal Burning
- Location: Not in My Backyard
- Costs are the following:
- 200 Million Dollars for basic 500 MW plant with
no pollution control
- operating costs are 4 cents per KWH (this includes cost of
delivery of coal)
- Add 200 million dollars in capital costs and 2 cents per
KWH in operating costs for each 50% reduction of emissions.
- Eugene city council demands a "low emission" plant (interpret
that however you want but take it to mean there must be at least
some pollution control)
5. Biomass Burning Facility
- Location: Willamette Valley
- Current crop yield is 2 Kilowatts (KW) per acre
- To plant, grow, harvest and transport crops to the
burning facility is $1000 per acre each year
- After each harvest there is some nutrient loss to
the soil which results in 5% reduction in annual yield
Okay that's it. I have tried to be fairly realistic with the above
numbers in order to reflect what the current costs are.
You are to build an energy model from this array of power generating
facilities and energy storage that you will be sustainable and
deliver energy at a reasonable cost to the consumer.
Your report should emphasize the four points outlined above.
Don't forget to factor in over-capacity as required
for energy storage. That is, your generating power for
immediate demand but also to be used at later times
(like when the sun isn't up or when the wind isn't blowing)