HomeMy WebLinkAboutKoyukuk Supplement Reconnaissance Study of Energy Requirements & Alternatives 5-1981
OF
ENERGY REQUIREMENTS & ALTERNATIVES
FOR
KOYUKUK
INTERNATIONAL ENGINEERING COMPANY, INC. A MORRISON-KNUDSEN COMPANY
ROBERT W. RETHERFORD ASSOCIATES DIVISION ALASKA POWER AUTHORITY
KOYUKUK SUPPLEMENT
TO
RECONNAISSANCE STUDY
OF
ENERGY REQUIREMENTS AND ALTERNATIVES
FOR
BUCKLAND, CHUATHBALUK, CROOKED CREEK
HUGHES, KOYUKUK, NIKOLAI, RED DEVIL,
RUSSIAN MISSION, SHELDON POINT, SLEETMUTE,
STONY RIVER, TAKOTNA AND TELIDA
MAY 1981
Prepared by:
Robert W. Retherford Associates
Arctic Division of International Engineering Co., Inc.
Anchorage, Alaska
- For the
State of Alaska
Department of Commerce and Economic Development
Division of Alaska Power Authority
333 West Fourth Avenue, Suite 31
Anchorage, Alaska 99501
Under Contract No. AS44.56.010
APA 20/T1
This report was prepared by:
Robert W. Retherford Associates
Arctic Division of International Engineering Company
R.W. Retherford, P.E.
Frank J. Bettine, E.1.T.
James J. Lard, E.1.T.
Mark Latour, Economist
Illustrations on the front cover were prepared and sketched by
Kathryn L. Langman. These illustrations portray several energy
resource alternatives investigated for the Thirteen Villages
included in this study.
APA 20/T2
TABLE OF CONTENTS
Section Page
1. Summary and Results 1.1
2. Recommendations 2.1
3. Existing Conditions and Energy Balance 3.1
4. Energy Requirements Forecast 4.1
5. Resource and Technology Assessment 5.1
6. Energy Plans 6.1
APPENDIX A Description of Selected Technologies
APA*32C1
SECTION 1
SUMMARY AND RESULTS
APA*32C2
SECTION 1
SUMMARY AND RESULTS
A. SUMMARY
A study was recently conducted under contract number AS44.56.010 for the
State of Alaska Department of Commerce and Economic Development, Divi-
sion of Alaska Power Authority to determine the energy alternatives for
Thirteen Western Alaskan Villages. This study consists of establishing
the following:
Energy Balance for 1979
Existing Power and Heating Facilities - 1980
Electric Power Requirements to the year 2000
Space Heating Requirement to the year 2000
Potential Energy and Electric Power Resources
Evaluation of the Electric Power Resources
Recommendations for the development or future studies
for the 13 Western Alaskan villages of Buckland, Hughes, Koyukuk, Telida,
Nikolai, Takotna, Stony River, Sleetmute, Red Devil, Crooked Creek,
Chuathbaluk, Russian Mission and Sheldon Point (See Figure 1.1)
The Koyukuk supplement represents a brief summary of the most pertinent
facts and findings contained in the original report which relate to the
village of Koyukuk. Detailed data concerning the village may be obtained
by referring to the original report.
Diesel fuels are presently used to satisfy the major percentage of energy
demands in the village. Emphasis in the study was therefore placed on
possible resources and technologies that could replace or at least supple-
ment the use of increasingly costly fuel oi]. The energy alternatives which
were selected for detailed evaluation in the village of Koyukuk include: +
1) Diesel generation
2) Waste Heat Recovery
3) Binary Cycle generation using wood fuel
4) Hydroelectric generation
5) Passive solar heating
6) Energy conservation
1 See Appendix A for brief description of technologies listed.
1-1
APA*32G1
Noatoh River '
. 2
/ 3
/ 9 ‘
“a ce 5
“oe a 6
a - oso \ 7
_—v> 8 | 9
Yukon - Tonon Yehae Tenens ¢ Plateau 10
| W
. 12 f
or ste Man 1 3
ncaa 13 | y 8. 12 t é \Susiina or
Talkeetna Say, Orange | v » Aivor | TP) PR ibs untains Wren Mul
a Po ey A Mig f 8 oO 2 ver v ANCHORAGE \ $ "tit ys ole
a =" , Ke. oy a S & Sw WY fp of” VAKUTAT 3
° 7 eo
Gulf of Aloske
g 9
Bristos BOY aia pACIFIC OCEAN
as
oS yh Co Den, 4 FIGURE 1.1
“ALASKA MAP
BUCKLAND
HUGHES
KOYUKUK
RUSSIAN MISSION
SHELDON POINT
CHUATHBALUK
CROOKED CREEK
NIKOLAI
RED DEVIL
SLEETMUTE
STONY RIVER
TAKOTNA
TELIDA
13 WESTERN VILLAGES
SECTION 1
SUMMARY AND RESULTS
To obtain a comprehensive understanding of future energy requirements
for the village, a control year - 1979 - was established from which all
projections have been made. Information related to village history,
population and economic conditions, plus information regarding village
government, transportation, power and heating facilities, fuel require-
ments, etc., was collected to provide the necessary background data to
support these projections.
B. EVALUATION RESULTS
1. Economics
Table 1.1 is a summary of the 20 and 50 year economic evaluations per-
formed for the combination of alternatives (i.e., energy plans) selected
for detailed study for Koyukuk. This Table lists the accumulated present
worth of plan costs and the accumulated present worth of the net benefits
derived from non-electrical outputs, where:
1) Plan costs represent the cost for providing electrical
generation, and
2) Net benefits represent the savings derived from ste heat
capture or surplus hydroelectric energy used for electric
heating.
a. Twenty Year Evaluation Results
Results of the 20-year economic evaluation indicate that the use of diesel
with waste heat recovery to be most economical energy plan examined for
Koyukuk.
The diesel generation plus binary generation with waste heat energy plan
averaged approximately 25 percent greater cost than the diesel generation
Plus waste heat recovery plan for Koyukuk.
APA*32G3
vol KOYUKUK
Table 1.1 Accumulated Present Worth of Plan Costs and Benefits ($1,000)
Diesel Diesel
& &
Diesel Binary Cycle Diesel WECS
PERIOD & & & &
Waste Heat Waste Heat Hydroelectric Waste Heat
Cost-Benefit Cost-Benefit Cost-Benefit Cost-Benefit
20-year 1886-187. 1 2357-136. 2 4300-53.2 N/A
50-year 4821-696.9 5389-569.9 9241-46.0 N/A
SECTION 1
SUMMARY AND RESULTS
Hydroelectric generation is found to be the most expensive method of
providing electrical energy for Koyukuk.
Passive solar and energy conservation have not been economically evaluated
in detail and they are, therefore, not listed in Table 1.1. Numerous past
studies have shown the value of conservation and passive solar heating. An
approximate fifteen percent reduction in fossil fuel requirements due to the
implementation of passive solar heating and energy conservation measures has
been built into the village Heating Requirement Forecast Tables listed in
Section 4. It is assumed that these two methods of reducing usage will be
implemented in the village.
b. Fifty Year Evaluation Results:
The results of the 50-year economic evaluation performed for the village
of Koyukuk confirms hydroelectric generation as the most expensive method
of providing electrical energy. The high cost of developing the potential
hydroelectric site located on the east tributary of the Nulato River makes
the use of hydroelectric generation economically unrealistic.
In addition, the results of the 50-year evaluation has reaffirmed the
cost advantage of diesel plus waste heat recovery, over diesel plus
binary cycle with waste heat recovery for the village of Koyukuk.
2. Environmental and Technical
Results of the environmental and technical evaluations are listed in Table
1.2. These results indicate the overall environmental and technical ranking
of energy plans selected for detail study for the village of Koyukuk in
order of preference to be:
1) diesel electric plus waste heat
2) diesel plus hydroelectric generation
3) diesel plus binary cycle generation with waste heat
1-5
APA*32G5
9-L APA 28M1
EVALUATION MATRIX
Diesel + Diesel + Diesel + Waste Heat
Table 1.2 Diesel Local Hydro Binary Generation Supplemental
Electric w/wo Electric Coal and/or Wood Wind
Factor + Waste Heat Heat With Waste Heat Generation
(A) Economic (Present Worth) B F Cc -
(B) Environmental
(1) Community Preference 9 1 4 -
(2) Infrastructure 3 4 5 =
(3) Timing 1 5 7 -
(4) Air Quality 4 1 5 -
(5) Water Quality 2 1 4 -
(6) Fish and Wildlife 2 5 4 -
(7) Land Use 2 6 4 -
(8) Terrestrial Impacts _2 6 4 a
TOTAL 25 29 37 -
Environmental Ranking 1 3 3 -
(C) Technical
(1) Safety 2 1 2 -
(2) Reliability 2 1 2 -
(3) Availability ms 5 _8 =
TOTAL 5 7 12 -
TECHNICAL RANKING 1 2 4 -
OVERALL RANKING B-1 F-2 C-3 -
SECTION 2
RECOMMENDATIONS
APA*32G7
SECTION 2
RECOMMENDATIONS
A. GENERAL
Analysis of both the 20-year and 50-year economic, technical and environ-
mental evaluations indicate the two most promising energy plans for the
village of Koyukuk in order of preference to be:
1) Continued use of diesel generation supplemented with waste
heat recovery,
2) diesel plus binary cycle generation supplemented with waste
heat recovery,
B. RECOMMENDED PLAN - Diesel Generation Supplemented with Waste Heat
Recovery. .
The 20 and 50 year economic, technical and environmental evaluation
indicate that diesel generation with waste heat recovery will provide
the most satisfactory method of providing electric energy for the village
of Koyukuk.
It is recommended, therefore, that a study be conducted to determine the
feasibility of utilizing waste heat in the village of Koyukuk. Such a
study should include a definitive review of the following items:
1) availability of waste heat
2) transportation of waste heat
3) end use of waste heat
C. FIRST ALTERNATIVE PLAN - Diesel Plus Binary Cycle Generation Supple-
mented With Waste Heat Recovery.
The first alternative plan, as listed above, is diesel plus binary cycle
generation with waste heat recovery. This plan averages approximately
25 percent greater costs than the recommended plan (20-year economic
evaluation). Because the uncertainties in the costs associated with
this alternative, such as the cost of wood fuel, equipment cost, etc.,
2-1
APA*32G8
SECTION 2
RECOMMENDATIONS
which can not at present be as precisely determined as for the recommended
plan, it is conceivable that this alternative could be cost competitive with
the alternative plan (i.e., diesel generation plus waste heat recovery).
Because binary cycle generation is viewed as one of the few potentially
viable energy alternatives, suitable for future use in remote Alaska
villages such as Koyukuk, it is recommended that the feasibility of binary
cycle generation in Alaska be further investigated in regard to:
1) Equipment availability
2) Technical feasibility
3) Economic aspects
4) Environmental aspects
5) Constraints
Binary cycle generation equipment in unit sizes suitable for village appli-
cation is, however, not expected to be available until the late 1980's,
D. COSTS FOR FURTHER STUDY
Approximate costs for determining of feasibility of the two most attractive
energy resources for the village of Koyukuk are:.-
e Waste heat recovery - approximately $2500
e Binary cycle generation - approximately $2,000,000 which
would include the cost of constructing and operating
a demonstration plant in Alaska.
E. CONSERVATION MEASURES
For the village to stabilize and hopefully reduce the local cost of
energy immediate short term conservation measures could provide the
most rapid results. These conservation measures, which include added
insulation, double glazing or solar film, arctic entrances, weather
stripping, etc., can reduce current non-transportation fuel use on the
order of 15 percent over the 20-year period of this study.
2-2
SECTION 3
EXISTING CONDITIONS AND ENERGY BALANCE
APA*32G10
SECTION 3
EXISTING CONDITIONS
AND ENERGY BALANCE
A. INTRODUCTION
To establish a base and understanding of energy use in the village, an
energy balance has been compiled for the year 1979. Input energy forms
are diesel, wood, propane, blazo, gasoline, and aviation gasoline.
Energy used in the village has been listed both by end use category
(i.e., heating, transportation, and quantities used for electrical
generation) and by consumer category to include residential, small
commercial, public buildings, and large users (school), in the following
table (Table numbered as in original report).
To provide background data, information related to village history,
demographic and economic conditions plus information regarding village
government, transportation, power and heating facilities is included.
a. GENERAL BACKGROUND INFORMATION
History: Koyukuk is situated approximately 30 miles
west of Galena on the right bank of the Yukon River.
Koyukuk was a trading post and Eskimo village listed
with a population of 150 in the 1880 census. Koyukuk is
located within the Doyon Limited Regional Corporation
boundaries.
Population: The 1970 population of Koyukuk was 114
residents. The 1980 population was estimated at 115 by
the city council. The population of Koyukuk has fluc-
tuated over the past few years, from a low of 100 in 1975
to a high of 124 in 1978 before a decline to the 1980
population level. The average population growth rate over
the past five years is less than one percent. In 1980,
the average number of members per household in the
community was 4.1 persons.
3-1
APA*32G11
APA*32G12
SECTION 3
EXISTING CONDITIONS
AND ENERGY BALANCE
Economy: Koyukuk exists primarily on a subsistence economy.
Moose and salmon are the most important food items with
rabbit, ptarmigan, grouse, waterfowl] and their eggs
supplementing the diet.
Permanent non-subsistence employment consists of
teachers, teacher aide, school cook, health aide, city
office workers, and store employees. Income is also
earned from trapping and the sale of pelts and further
supplemented through public assistance payments.
Transportation: The community's location on the Yukon
River allows access by air, river barge and small boat
travel. Fuel oi] and other bulk supplies are trans-
ported to the community by river barge. Passengers,
small cargo items, supplies and mail arrive by air.
Small boats are the primary means of transportation
during the summer month. Snowmachines are used for winter
transportation. -
There are no roads connecting Koyukuk with other communi-
ties in the region.
ENERGY BALANCE (1979)
The residentiat heating needs in Koyukuk are supplied
from wood. Public buildings and the school rely on
diesel fuel oi] for heating. Village heating require-
ments account for 63.7 percent of the total energy usage
of the village, followed by electric generation at 19.5
percent and transportation with 16.8 percent. Graph 3.3
illustrates by consumer category, the types and per-
centages of energy forms used in the village. Table 3.2
tabularizes this data in additional detail.
3-2
APA*32G13
SECTION 3
EXISTING CONDITIONS
AND ENERGY BALANCE
EXISTING POWER AND HEATING FACILITIES
Electric Power: No centralized power generation facility
now exists in Koyukuk. Construction of a village owned
and operated power and distribution facility is, however,
expected to begin in the Spring of 1981.
Presently the school maintains and operates its own
generation facilities which supplies electrical power to
the school, the PHS building and other public facilities
within the villages. The school generation facilities
consist of a 100-kW, a 75-kW and a 30-kW diesel-generator
set.
Heating: Residential and commercial heating are almost
entirely from wood fuel using individual woods stoves.
Average usage per residence is approximately nine cords
of wood per year. Heating of the community hall, clinic
and PHS building as well as the school is with fuel oi].
Fuel Storage: Diesel, bulk fuel oi] storage capacity in the
community (village + school) is approximagely 53,000 gallons
(estimated during site visit).
GRAPH 3.3 1979 ENERGY BALANCE
KOYUKUK
EFFICIENCIES ASSUMED: LEGEND _
HEATING — 75% GS — RESIDENTIAL TRANSPORTATION — 25% [) — SMALL COMMERCIAL ELECTRICAL GENERATION — 25% [==] — pustic BUILDINGS
(EE) — LARGE USERS (SCHOOL)
() — WASTE HEAT
TOTAL ENERGY (100%) 1.3%
HEATING (63.7%)
BLAZO) — 1.1%
PROPANE— 0.2%
WOOD — 36.7%
TOTAL — 63.7%
TRANSPORTATION (16.8%)
L-—_.— GASOLINE + AV GAS 16.8%
ELECTRICAL GENERATION (19.5%)
—- DIESEL 19.5%
| | | | | | | | | | | | | | | | | |
0 2000 4000 6000 8000 10,000 12,000 14,000 16,000
BTU x 10°
DIESEL — 25.7%
| 18,000 20,000
G-e apa28:al0
ENERGY BALANCE - 1979
KOYUKUK
Table 3.3
CONSUMER ENERGY FORM CONSUMED
HEATING TRANSPORTATION ELECTRICAL
DIESEL wooD PROPANE BLAZO GASOLINE AV GAL DIESEL TOTAL
GAL CORDS POUNDS GAL GAL GAL GAL 10° Btu
TYPE NO. 10° Btu 10® Btu 10° Btu 10" Btu 10° Btu 10® Btu 10° Btu % of Total
Residential 28 = 252 - 1,000 15,400 - - 6 , 368
4,284 129 1,955 54.5
Smal] Commercial 2 1,100 7 7 - - - 7 152
152 1.3
Public Buildings 3 2,200 - - - - = 3,600 801
304 497 6.9
Large User (school) 1 18,460 1,200 - = - 2,880 4,347
2,547 23 1,777 37.3
Total 34 21,760 252 1,200 1,000 15,400 - 6,480 -
3,003 4,284 23 129 1,955 2,274 11,66
% of Total Btu 25.7 36.7 0.2 1.1 16.8 19.5 100
Waste heat 10° Btu 751 1,071 6 32 1,466 - 1,706 5,032
% of total Btu 6.4 9.2 0.1 0.3 12.6 14.6 43.2
Assuemd efficiency:
Heating - 75%
Transportation - 25%
Electric Generation - 25%
SECTION 4
ENERGY REQUIREMENTS FORECAST
APA*32G14
SECTION 4
ENERGY REQUIREMENTS
FORECAST
INTRODUCTION
The following paragraphs and tables outline the planned capital
projects, economic activities forecast, and energy end use
forecasts for the village of Koyukuk.?
1 Tables numbered as in original report
4-1
APA*32G16
APA 22-A/C1 SECTION 4
ENERGY REQUIREMENTS FORECAST
3. Koyukuk
(a)
(b)
Planned Capital Projects and Economic Activity Forecast
Planned Capital Projects:
Scheduled improvements - Airport improvements
Electrification
Potential developments - Timber harvest
Reopening of Williams Coal Mine
Economic Activity Forecast: Employment for several families
from Koyukuk would result from the reopening of the Williams
Coal Mine or timber harvest operation in the area for the pur-
pose of supplying coal and wood for heating and electrical
generation for Koyukuk and the Lower Yukon. Development of
these resources is, however, not anticipated until the late
1980's. No significant economic activity is expected in the
immediate future.
Population Forecast - Koyukuk
The population forecast is shown in the following Table 4.3
Table 4.3
Year 1970 1979 1982 1985 1990 2000
Population 114 115 117 121 127 140
# Residences - 28 * 28 30 32 35
# Small commercial - 2 2 3 3 4
# Public users - 3 3 3 6
# Large users - 1 1 1 1 1
Population growth rate - 1%
(c)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
apa22:al0
End Use Forecast
The end uses of energy are shown in the following Tables 4.3a, 4.3b,
KOYUKUK ELECTRIC POWER REQUIREMENTS +
and 4.3c.
Table 4.3a
1979
Population 115
Number of residential
consumers -
Average kWh/mo/consumer -
MWh/year residential consumers
(2) x (1) x 12 + 1000 =
Number of small commer-
cial. consumers -
Average kWh/mo/consumer 7
MWh/year small commer-
cial consumer
(4) x (5) x 12 + 1000 -
Number of public consumers 3
Average kWh/mo/consumer 850
MWh/year public consumer
(7) x (8) x 12 + 1000 30.6
Large (LP) consumer 1
(school)
Average kWh/mo/LP 9,125
consumer 2
MWh/year LP's
(10) x (11) x 12 + 1000 109.5
System MWh/year
(3)+(6)+(9)+(12) 140.1
System load factor 0.6
System demand kW
(13)+8760+(14)x1000 27
1982
117
28
133
44.7
848
20.4
970
34.9
9,400
112.8
212.8
0.45
54
Electrification scheduled for summer 1981
School at 1% growth rate
4-3
1985
121
30
160
57.6
968
34.8
1,107
39.9
9,686
116.2
248.5
0.45
63
1990
127
32
220
84.5
1,204
43.3
1,379
66.2
10,180
122.2
316.2
0.45
80
2000
140
35
415
174.3
1,872
89.9
2,142
154.2
11,245
134.9
553.3
0.50
126
(1)
(2)
(3)
(4)
apa22:cl0
Table 4.3b
Population
Number of resi-
dential users
Diesel - Average
gal/mo/residence (6)+(2)+12
Propane - Average
1bs/mo/residence
(7)+(2)+12
(5) Wood - Average
(6)
(7)
cords/mo/res idence
(8)+(2)+12
Diesel Gals
Btu x 105
Propane __Lbs Btu x 106
(8) Wood Cords
(9)
(10)
Btu x 10®
Total Btu x 106
(6)+(7)+(8)
Annual per capita
consumption Btu x 106 (9)+(1)
Assumes a one percent per year decrease in fossil fuel requirements
KOYUKUK HEATING REQUIREMENTS?
RESIDENTIAL CONSUMERS
1979
115
28
0.75
37.3
1982
117
28
0.75
252
4,284
4,284
36.6
1985
121
30
38.2
1990
127
32
19
4,802
37.8
2000
140
35
35
34.6
beginning in 1986 due to implementation fo passive solar heating and
technical improvements in both building design and heating equipment.
4-4
apa22-A: R2
Table 4.3c
KOYUKUK HEATING REQUIREMENTS 2
OTHER CONSUMERS
1979 1982 1985 1990 2000
(11) Smal] Commercial 2 2 3 3 4 user
(12) Diesel 1100 1100 1650 1569 1894 Gals/Btu x 106 152 152 228 217 261
(13) Public Buildings 3 3 3 4 6 ‘ user
(14) Diesel _ Gals 2200 2200 2200 2639 4326 Btu x 10° 304 304 304 364 597
(15) Large users i 1 2 1 1 (school)
(16) Diesel equivalent
(diesel + wood)
Gals 18,460 18,460 18,460 17,555 15,894 Btu x 10° 2,547 2,547 2,547 2,423 2,193
(17) Propane Lbs 1200 1200 1200 1141 1033 ~ Btu x 10° 23 23 23 22 20
(18) Subtotal
Btu x 106
(16)+(17) 2,571 2,571 2,571 2,445 2,213
(19) Total
Btu x 106
(9)+(12)+(14)+(18) 7,311 7,311 7,729 7,828 7,913
1 Assumes a one percent per year decrease in fossil fuel requirements begin- ning in 1986 due to implementation of passive solar heating and technical improvements in both building design and heating equipment.
4-5
SECTION 5
RESOURCE AND TECHNOLOGY ASSESSMENT
APA*32G16
SECTION 5
RESOURCE AND
TECHNOLOGY ASSESSMENT
A. ENERGY RESOURCE ASSESSMENT
The energy resources which are determined to be available for the village
of Koyukuk are summarized in the following table. Information concerning
approximate quantity, quality, availability, cost, source of data and
important comments is included. The energy resources specifically
addressed include diesel generation, wind, hydroelectric potential,
waste heat utilization, timber and coal. While passive solar heating
and energy conservation are not specifically addressed in the table, it
is assumed these two energy conservation measures will be implemented in
the village. Energy resources which are not available for use in Koyukuk
and are therefore not addressed include geothermal, peat, solid waste,
oil and gas and tidal power.
APA*32G17
2-s APA22-A S2
Table 5.3
ENERGY
RESOURCE
Diesel fuel
Wood fuel
Coal fuel
Waste Heat
Recovery
Hydroelectric
potential
Wind Potential
ENERGY RESOURCE ASSESSMENT
KOYUKUK
SOURCE OF
LOCATION QUANTITY/AVAILABILITY QUALITY COST DATA
Major suppliers - #2 diesel $1.56/gal Nenana Fuel
Nenana 128,000 Btu/gal $11.31/10° Btu Dealer
10-mile radius 29x10® cu ft; 14.6x10® Btu/cord $132/cord Appendix G
late 1980's $9.04/10® Btu
Williams Mine 14,000 tons minimum 11,000 Btu/1b $220/ton Appendix H
late 1980's 22x10® Btu/ton $10.00/10® Btu
7 30% of fuel used for Recoverable heat $450/kW installed Appendix D
electrical generation; 41,400 Btu per <$5.93/10® Btu>
upon installation at gallon diesel diese! fuel displaced
school or new power equivalent.
plant.
East tributary 157 kW; 440 mwh/yr - $49 ,600/kW Reference #37
of Nulato River Estimated on line 1986 installed
Villagers indicate insufficient wind in village for wind power. Possibility of
wind generator atop bluffs near village, but no wind data available.
' Assumes $1.56 per gallon diesel fuel costs, 0.45 load factor
< > Savings per million Btu's recovered.
RESTRICTIONS
Delivered cost
at village.
Delivered cost
at village.
Delivered cost
at village.
Cost assume heat delivery
within 100 ft radius of
plant. Availability varies
with generator loading.
Maintenance at $11/kW/yr.
SECTION 6
ENERGY PLANS
APA*32G18
SECTION 6
ENERGY PLANS .
A. INTRODUCTION
The approach to the energy plans formulated for the village of Koyukuk
is explained in this section. Each plan is formulated to meet the
forecasted electrical energy requirements of the village plus addi-
tional related requirements, such as space heating, where appropriate.
A base case plan using diesel generation is formulated for the village.
This plan is used as the "control case" to determine the advantage or
disadvantage of other alternatives as compared to diesel generation.
Future village diesel generation additions assume that the local school,
which has sufficient installed generation capacity, will provide its
own back-up capability. The school will, however, rely on the central-
ized village power plant for their primary supply of electrical power
and energy.
A wook-fired binary cycle generation option is presented for the village
of Koyukuk. It is assumed the wood needed for fuel would be harvested
within a 10-mile radius of Koyukuk. Diesel fuel oil-fired binary cycle
generation is also possible, but provides no significant cost or technical
advantage over diesel engine powered generation. Fuel oil-fired binary
cycle generation is, therefore, not included in the formulated energy plan
for the village.
A waste heat capture analysis is included with all options that
use fossil fuels for electrical generation (i.e., diesel generation
employing engine jacket water cooling, and binary cycle generation).
Hydroelectric generation is investigated for the village. Any additional
benefits from this technology, such as the use of excess hydroelectric
energy to provide electric space heat is also included.
6-1
APA*32G19
SECTION 6
ENERGY PLANS
a) Base case plan
Plan components - Diesel and waste heat recovery
2. Timing of system additions
Diesel 1981 - 75 + 50 kW, 1986 - 75 kW
Waste heat equipment - 1983 - 75 kW, 1986 - 75 kW
3. Plan description - This plan assumes the continued
use of diesel driven generation throughout the
study and the implementation of waste heat recovery.
b. Alternative Plan A
1. Plan components - Diesel and binary cycle generation
using wood fuel and waste heat recovery.
2. Timing of additions -
, Diesel - 1981 - 75 + 50 kW, 1986 - 75 kW
Binary cycle - 1989 - 150 kW
Waste heat equipment - 1983 - 75 kW, 1986 - 75 kW,
1989 - 150 kW.
3. Plan description - This plan assumes construction
of wood-fired binary cycle generator facilities
in the late 1980's as a replacement for diesel
generation and the implementation of waste heat
recovery.
c. Alternative Plan B.
1. Plan components - diesel and hydroelectric
2. Timing of additions
Diesel - 1981 - 75 + 50 kW, 1986 - 75 kW
Hydroelectric - 1986 - 157 kW, 440 mWh/yr
6-2
APA*32G20
APA*32G21
SECTION 6
ENERGY PLANS
Plan description - This plan assumes construction
of a hydroelectric project on the east tributary to
the Nulato River (Ref. 37) as replacement for diesel
generation and to provide supplemental electric
space heating during three years when surplus
hydroelectric energy is available. Estimated 1980
construction cost of the hydroelectric project and
transmission line is $7,792,900 (Ref. 37).
APPENDIX A
DESCRIPTION OF SELECTED TECHNOLOGIES
APA*32G22
A.1 DIESEL
a. General Description
1)
2)
APA*32C35
Thermodynamic and engineering processes involved
In the diesel engine, air is compressed in a cylinder to a
high pressure. Fuel oi] is injected into the compressed air,
which is at a temperature above the fuel ignition point, and
the fuel burns, converting thermal energy to mechanical energy
by driving a piston. Pistons drive a shaft which in turn
drives the generator.
Current and future availability
Diesel engines driving electrical generators are one of the
most efficient simple cycle converters of chemical energy
(fuel) to electrical energy. Although the diesel cycle in
theory will burn any combustible matter, the practical fact of
the matter is that these engines burn only high grade liquid
petroleum or gas, except for multi-thousand horsepower engines
which can burn heated residual oi7. Diesel generating units
are usually built as an integral whole and mounted on skids
for installation at their place of use.
A-1
A.2 BINARY CYCLE FOR ELECTRICAL GENERATION
a. General Description
1)
2)
APA*32C36
Thermodynamic and engineering processes involved
In the binary conversion process, a heated primary fluid of
insufficient quality for direct use in electrical production
passes through a heat exchanger to transfer heat to a working
fluid. The working fluid has a lower boiling point than water
and is vaporized in the heat exchanger. The vaporized working
fluid then expands through a turbine or cylinder piston arrange-
ment is condensed, and returns to the heat exchanger. The primary
fluid is returned to its heat source following heat exchange.
Current and future availability
Current commercial availability is restricted to unit sizes
in excess of village power requirements as determined in this
study. Binary cycle generation equipment in unit sizes suit-
able for village application is not expected to be available
until the late 1980's.
A.3 HYDROELECTRIC GENERATION
a. General Description
ne
APA*32C37
Thermodynamic and engineering processes involved
In the hydroelectric power development, flowing water is
directed into a hydraulic turbine where the energy in the
water jis used to turn a shaft, which in turn drives a gener-
ator. In their action, turbines involve a continuous trans-
formation of the potential and/or kinetic energy of the water
into usable mechanical energy at the shaft. Water stored at
rest at an elevation above the level of the turbine (head)
possesses potential energy; when flowing, the water possesses
kinetic energy as a function of its velocity. The return of
the used water to the higher elevation necessary for funct-
joning of the hydroelectric machinery is powered by the sun
to complete the cycle - a direct, natural process using solar
energy. The ability to store water at a useful elevation makes
this energy supply predictable and dependable.
Current and future availability
Hydroelectric developments in the United States, as. of January
1978, totaled 59 million kilowatts, producing an estimated
average annual output of 276 billion kilowatt hours according
to the U.S. Department of Energy (DOE). Hydropower provides
about 10% of Alaska's electric energy needs. Developments
range in size from over a million kilowatts down to just a few
kilowatts of installed capacity. Hydropower is a time proven
method of generation that offers unique advantages. Fuel
cost, a major contributor to thermal plant operating costs, is
eliminated.
A.4 WIND ENERGY CONVERSION SYSTEMS (WECS)
a. General Description
1)
2)
APA*32C38
Thermodynamic and engineering processes involved
The thermodynamic process involved stems from the sun, the
primary energy source which produces the wind. This wind
energy cannot be stored, is intermittent, somewhat unpredict-
able and thereby undependable. The process then relies
on wind flow over an air foil assembly to create differential
pressures along the air foil. This differential pressure
results in rotation of the assembly around a fixed axis to
which it is attached. Power from the wind is transmitted
through the connection shaft and accompanying gear box to an
electrical generator. ;
Three types of generators are presently in use with wind energy
systems. These are the DC generator, the AC induction generator
and the AC synchronous generator. Of the three types, the AC
induction generator is the most widely used because of its
simplicity and low cost. An induction generator is not a stand-
alone generator and must be connected to an external power system
of relatively constant frequency and voltage to operate properly.
Current and future availability
Availability of the wind at useful velocities require long
term records to estimate the potential energy. Lesser records
provide less credible estimates.
Availability of WECS machinery in small size units in the 1.5 kW
to 20 kW range is good. Large units in the 100-200 kW range are
currently undergoing tests in both the government and private sector
and should be available in the near future. Demonstrations of
multi-megawatt sizes are in process.
A-4
A.5 DIESEL WASTE HEAT RECOVERY
a. General Description
1)
2)
APA*32C39
Thermodynamic and engineering processes involved
The present use of fossil fuels (coal, gas, oil) in Alaska (as
- elsewhere) to produce more useful forms of energy (heat,
electricity, motive power) is less than 100 percent efficient.
For example, if a machine burns a certain quantity of fossil
fuel and produces useful output (shaft horsepower, electrical
energy, steam, useful hot water or air for space heating)
equivalent to 30% of the fuel burned, the energy represented by
the remaining 70% of the fuel will appear as unused or "waste"
heat. Such heat most often appears as hot exhaust gas, tepid
to warm water (65°F-180°F), hot air from cooling radiators, or
direct radiation from the machine.
Diesel waste heat can be recovered from engine cooling water
and exhaust, or either source separately. The waste heat is
typically transferred to a water-glycol circulating system in
Alaskan applications. The heated circulating fluid can be used
for space, water, or process heating where temperatures of
the waste hear are suitable.
Current and future availability
Recovery of diesel waste heat in Alaska is growing as a result of
sharp increases in diesel fuel cost. Recovery of jacket water heat
only is most common in Alaska.
Diesel waste heat availability is directly related to the
location and operating cycles of the engine installations.
A-5
A.6 PASSIVE SOLAR HEATING
a. General Description
Passive solar heating makes use of solar energy (sunlight) through
energy efficient design (i.e. south facing windows, shutters, added
insulation) but without the aid of any mechanical or electrical
inputs. Space heating is the most common application of passive
solar heating. Because such solar heating is available only when the
sun shines its availability is intermittent (day-night cycles) and
variable (winter-summer-cloudy-clear).
A-6
APA*32C40
A.7 CONSERVATION
a. General Description
1)
2)
APA*32C41
Thermodynamic and engineering processes involved
Conservation measures considered here are mainly classified as
"passive". Passive measures are intended to conserve energy with-
out any further electrical, thermal, or mechanical energy input.
Typical passive measures are insulation, double glazing or solar
film, arctic entrances and weather stripping. Energy conservation
characteristics of some passive measures degrade with time, which
must be considered in the overall evaluation of their effectiveness
for an intended life cycle. Other conservation measures includes
improvement in efficiency of utilization devices (such as motors)
and "doing without" energy by disciplines (turning off lights,
turning down thermostats). .
Current and future availability
Materials and schemes to implement passive measures are commer-
cially available and increasing in use all over the United States
due to the rapidly escalating cost of energy.
La
Alaska Power Authority 334 W. 5th Ave. Anchorage, Alaska 99501