Waterfall at Jomo'i Gul Chhu |
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Feasibility Report
Rolwaling Hydropower Project
Gaurishankar VDC-4, BedingDolakha
Submitted to
Bridges: Projects in Rational Tourism Development
http://www.bridges-prtd.com
Ithaca, New York, USA
E-mail: info@bridges-prtd.comPrepared by
Forum for Energy and Environment Development (P) Ltd.
GPO Box: 12756, Tel: 521934
Kopundol, Lalitpur
Nepal
E-mail: feed@enet.com.npJanuary 2002
Abbreviations Used in This Report Chapter 2: Socio-Economic Study
Chapter 3: Hydropower End-Uses
Chapter 4: Site Selection and Structures Chapter 5: Implementation Procedure Appendix: Detailed Cost Estimate
|
Rolwaling Hydropower Project Distance from Nearest Road: 3 – 5 days Beneficiaries: 66 private households; school; monastery Project Cost: NRs. 1,076,374 (US$ 14,351.64) Sponsor: Bridges-PRTD Consulting and Implementing Engineers: FEED (P) Ltd.
Technical Parameters
Turbine and Generator
Transmission
CFL: compact florescent lamp CGI: corrugated galvanized iron FEED: Forum for Energy and Environment Development GI: galvanized iron HDPE: high density polyethylene HH: household HMG: His Majesty's Government (national government of Nepal) IGC: induction generator controller kW: kilowatt (1000 watts) km: kilometer m: meter MCB: miniature current breaker MHP: micro hydropower MS: mild steel MW: megawatt (1,000,000 Watts) NR: Nepalese rupee(s) PV: photovoltaic Rm: running meter Sq km: square kilometer VDC: Village Development Committee |
Figure 1.1A. Map of Nepal showing location of Rolwaling |
Despite its assets, Nepal is beset with intractable ecological and social problems. These include a high rate of deforestation, particularly critical inasmuch as fuel wood is the currently the primary source of energy. Nepal is one of the least developed countries in the world; per capita income is $210, and nearly half the population, estimated at 23.5 million, live below the poverty line. Health standards are among the poorest in the world. Gender inequity is widespread and deeply rooted in social and economic factors. The majority of women are illiterate; although they are primarily responsible for subsistence agricultural work as well as household activities, they are customarily deprived of income-generating opportunities.
Figure 1.1B. Map of Dolakha district showing project location |
In a country with limited marketable resources and minimal industrial development, agriculture is the mainstay of the economy, providing a livelihood for over 80% of the population and accounting for 41% of GDP. The primary sources of hard currency are tourism, textile exports, and foreign aid. Tourism is generally regarded as the best avenue for greater economic opportunity, but is restrained by poorly developed infrastructure and basic services -- especially transportation, communications, waste disposal, security, and electricity. Electricity in particular is perceived as critical to improving the quality of life of rural communities, reducing dependence on fuel wood, and expanding possibilities for tourism development. Since no gas or petroleum reserves have been found, and only low-grade coal, the only viable means of the generating electricity is water power. Nepal is, fortunately, very rich in water resources, and has a high potential for production of hydropower.
In Nepal, hydropower projects are classified as follows:
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Given the extremely dynamic character of the Nepalese Himalayas, huge hydro projects are not technically feasible; micro hydropower (MHP) projects, on the other hand, have been quite successful.
Beding, the site of the proposed Rolwaling Hydropower Project, is a remote and impoverished community of about 325 residents in Ward 4, Gaurishankar VDC, Dolakha district. Spread out over 3 settlements (Nyimare, Beding, and Na, from west to east) spanning half the length of Rolwaling Valley, Beding is 3 to 5 days’ walk from the nearest road head. There is a school that generally functions for part of the year, being closed during the cold season; there is no clinic, no police or postal service, no telephone, and no electricity. Virtually all of Beding’s able-bodied men – except a handful of clergy – seek employment in tourist services outside Rolwaling for at least half the year. When asked what change they would most like to see in the near future, the villagers are unanimous: electricity.
Figure 1.1C. Topographic map of Rolwaling Valley showing project location | PLATE 1.1A Nyimare |
PLATE 1.1B Nyimare | PLATE 1.1C Beding |
With respect to Beding, MHP has several advantages:
Dr. Seth Sicroff and Empar Alos Alabajos (ind. eng.), the directors of Bridges: Projects in Rational Tourism Development (Bridges-PRTD), have initiated this Peltric set project in conformity with the wishes of the villagers, who are voluntarily contributing labor and locally-available materials. This report is the outcome of a feasibility survey conducted by the technical team of Forum for Energy and Environment Development (FEED) Pvt. Ltd., Nepal. The survey was carried out during the last week of November 2001 as per the contract between Bridges-PRTD and FEED.
Beding (3650 m) is a rural village situated in Gaurishankar Village Development Committee (VDC). Since the village is too far from the national grid, the government has no plan to provide electricity within the next five or six years. Therefore, an initiative to generate power locally is the only option.
By foot, it takes 3 to 5 days to reach Beding from the trailhead at Dolakha. The most cost-efficient means of transporting equipment and materials for the MHP is by helicopter.
Due to the extreme variation in elevation from valley floor to the highlands, Rolwaling experiences a wide range of climatic zones, from warm temperate to arctic. At the proposed MHP site, the climate is moderate temperate, with night-time temperatures consistently dropping below freezing between mid December and mid-February. Winter poses a potential problem for MHP: very low rates of precipitation and also frozen run-off streams can greatly reduce water flow.
Rolwaling is an east-west valley blocked on the east and south by high mountain ridges, which means that it is not subject to as intense a monsoon season as many of the north-south valleys in eastern Nepal. Still, the seasonal variation in rainfall is sufficient to impact construction: the best time for plant installation is either spring or autumn.
1.4 Energy
Demand: Present and Future
Before proceeding with the survey, we consulted with the villagers, VDC representatives, and local entrepreneurs in order to identify their needs and possible end uses for power generated by the project implementation. Per-capita fuel wood consumption in Beding village is estimated at 450 kg/day; kerosene consumption is negligible due to the high cost and inconvenience. At present, virtually all fuel wood is used for cooking; none is used directly for lighting or heating, although a substantial quantity of fuel is used for the preparation of tea, which is consumed in large quantities primarily as a source of warmth.
PLATE 1.4A. Waterfall at Jomo'i Gul Chhu |
The total number of households in Beding is 66, with a population of about 325. In addition, prospective consumers include the Beding gompa (monastery) and the primary school. The power produced by the proposed project will be 3 kW, which can meet the present demand for lighting in the evening and other end uses. An average of 40 watts per household will be made available, plus 200 each for the school and the gompa. However power consumption during daylight hours must be managed in order to support commercial activities, primarily for tourism services and cottage industries.
Approximately 1 to 2 new houses are being built each year in Rolwaling. This indicates that the demand for electricity will be increasing slightly each year. For the coming three to five years the project can meet demand by using 7-watt compact florescent lamp (CFL) technology. For the longer term, other energy sources including solar photovoltaic (PV) home systems, are possible.
Jomo’i Gul Chhu is the water source for the proposed Peltric
set project. The source is glacier fed and perennial. Due to the presence of
other water sources, this stream is not used for drinking or other household
purposes. Only a small portion of the current is to be diverted for power
production, and the natural flow is adequate even during the leanest flow
season. Hence there are no problems regarding water rights.
PLATE 1.4B. Waterfall at Jomo'i Gul Chhu | PLATE 1.4C. Waterfall at Jomo'i Gul Chhu |
1.5 Plant
Capacity and System Efficiency
Plant capacity is based on the discharge, head, and efficiency of the equipment to be used in the plant. Studies show that if the discharge and head taken for the plant are 15 l/s and 40 meters respectively; plant efficiency will be 55%. This produces slightly more than 3 kW of power, which will be sufficient to meet the current needs of the village. With an average distribution of 40 watts, each household will be able to use 5 CFL bulbs, sufficient for work, study, and recreational use.
The entire population of the project area belongs to the Sherpa ethnic group. Subsistence-level agriculture is the economic mainstay; virtually all arable land is devoted to potatoes, with minimal cultivation of greens and radish. Arable land is limited, due to the topography and climate. Animal husbandry is also important: yaks are bred for milk, and cattle-yak crossbreeds are sold for cash; goats are sold for meat, and sheep are raised for wool. Since the 1970s, many residents have been engaged in tourism services outside the valley. Although the per capita income of Beding residents is on average well below the poverty line, there are sufficient actual and potential resources to sustain the Rolwaling Hydro Project.
As a result of the seasonal absence from Beding of most of the men, who are engaged in tourism services, the year-round residents are primarily women and children. A high priority must be to provide educational and economic opportunities for these people, particularly during the late fall and winter when the school is closed due to the cold weather and there are virtually no agricultural chores. Electricity will enable the upgrading of the local school, and relieve the burden on many families who find it necessary to send their children to schools outside Rolwaling.
Rolwaling Valley has considerable potential as a tourist destination. For the past decades, development has been stymied due to restrictive permit regulations which effectively prevent independent trekking. Essentially all visitors arrive with fully-equipped commercial tours, and spend little or nothing in Beding. At present these regulations have been relaxed, but development will be delayed for some time due to the absence of basic services. Installation of electrical power will assist considerably in expediting development, providing opportunities for local employment, and resulting in the correction of social and economic distortions that arise from the tendency of most adult males to seek employment in tourism services outside the valley.
Beding residents suffer from numerous health problems. Alcoholism is prevalent, due in part to the absence of recreational opportunities. Lack of running water, and in particular of hot water for bathing and washing, laundry, and proper washing of dishes and kitchen utensils, results in gastro-intestinal and skin disorders. Dependence on open stoves without chimneys for heating results in respiratory illnesses, particularly chronic bronchitis. All of these problems would be partially or fully alleviated with adequate supply of electrical power. While the small plant currently envisioned would not provide such a supply, it is expected that this plant will be a first step, creating a demand for more power as people realize the potential benefits.
The following are potential uses for power generated by the proposed Rolwaling Hydropower project. They will enhance opportunities for employment and income-generating activities in the future.
Figure 4. Rolwaling Hydropower Project layout plan |
The water from the stream is tapped directly into GI pipe of 50-meter length to the forebay and discharge into HDP (10-kgf pressure carrying capacity) penstock pipe.
Figure 4.2A. Penstock profile |
The forebay is designed so as to act as a de-sanding basin
for the sedimentation of silt particles. The forebay is also an inlet chamber of penstock pipe; hence, care should be taken to safeguard the turbine from cavitation. The proposed size of the forebay is 1.75 m long, 1.0 m wide and 1.0 m deep; this will reserve water for 4 minutes on approach to the turbine. Both the flushing set and the overflow system will be incorporated into
the forebay in order to facilitate silt removal. Excess water in the forebay will be channeled to the nearest natural drains.
Figure 4.2B. Forebay: Trace Rack Detail |
Figure 4.2C. Forebay: Section at B-B |
Figure 4.2D. Location of Forebay |
Figure 4.2E. Forebay: Section at A-A |
Figure 4.2F. Forebay Plan |
The penstock pipe connects the forebay tank with the turbine. To make the project cost effective and less complicated HDP pipe with 100-mm internal diameter and 10-kgf is recommended for this scheme.
If possible, the whole length of HDP pipe should be buried at a depth of 60-100 cm; otherwise GI pipe will be employed. For the buried pipe, anchor blocks and supporting piers are not required; this will help minimize the cost of the project. Similarly, expansion joints are not necessary for the HDP pipe, since it can move easily under the forebay inlet point. A final determination as to the need for steel pipe anchors and supporting piers will be made in the course of the pre-installation survey.
A powerhouse is to be constructed to house the Peltric set power generator. Locally available construction materials and local technology is preferred for the construction of the powerhouse in order to make the project cost effective and to provide an opportunity to develop the skills of the local people. The recommended internal size of the powerhouse is 3.5 x 2.5 x 2.5 meters.
Figure 4.4A. Powerhouse Plan | Figure 4.4B. Powerhouse: Section at A-A | Figure 4.4C. Powerhouse: Front Elevation |
Figure 4.6A. Transmission Line Detail: Construction Standards |
The main load centers are shown in the schematic plan of the transmission and distribution in the appendices of this report. The measured length of the transmission line is 2.1 km and distribution is about 0.7 km. Locally available wooden poles are suggested for supporting the transmission line. The total number of poles will be 70, and the distance between each pole will be 40 m on average.
Figure 4.6B. Principal Diagram of Power System | Figure 4.6C. Details of Stay Sets |
The preliminary project cost includes the cost of installation and operation. Installation cost means the investment during the commissioning process, which includes the cost of civil construction, electro-mechanical equipment, erection, labor, and so on.
The estimate of installation costs is based on prior experience with similar schemes as well as on data collected at the time of the field visit regarding the price of material available from the local market, local labor and transportation costs.
|
Description
|
Amount (NR)
|
Amount (US $)*
|
A |
Civil work |
86,500 |
1146.67 |
B |
Electro-mechanical |
586,925 |
7825.67 |
C |
Transport of materials by
helicopter |
67,500 |
900.00 |
D |
Survey and design |
66,000 |
880.00 |
E |
Installation |
75,000 |
1000.00 |
F |
Supervision |
50,000 |
666.67 |
G |
Subtotal (D + E + F) |
191,000 |
2546.67 |
H |
Subtotal (A+B+C+G) |
931,925 |
12,424.67 |
I |
VAT (10% of H) |
93,193 |
1,242.47 |
J |
Total (H+I) |
1,025,118 |
13,668.24 |
K |
Contingencies (5% of J) |
51,256 |
683.41 |
|
Grand Total (J+K) |
1,076,374 |
14,351.65 |
* Conversion is based on the rate of 75 Nepalese rupees to the American dollar.
A three-phase work plan has been proposed. In elaborating the extent of work for these phases, the following operations were taken into account:
Phase 1
Phase 2
Phase 3
6.1 Analytical Assumptions
Micro-hydro power projects cannot be justified on the basis of financial covenants prescribed by standard financial analysis in remote areas of Nepal, where transport cost only constitutes about one-half of the total investment cost. Therefore, the calculation of BC ratio, net present value and internal rate of return are meaningless. MHP projects in such areas can never be commercial ventures. The investment decision cannot be based on conventional parameters. If investment decisions are taken on such parameters, there will not be any projects and the socio-economic situation will never improve.
Consequently, a new approach must be followed to evaluate the projects such as the Rolwaling Hydropower Project. Sustainability rather than profitability should be emphasized. Can the operation and maintenance of the project run smoothly with the revenue generated from the project? If this is possible, the project will be sustainable. Having analyzed the needs and motivation of the Beding community, we find that:
6.2 Sources of Funding
His Majesty’s Government (HMG) of Nepal has announced a new subsidy policy for the development of Peltric sets and MHP in rural areas of the country. Considering the prevailing subsidy policy, the community will receive a subsidy of NR 55,000 (US$733) per kilowatt, or NR 165,000 (US$2200) for this project.
|
Sources of finance |
NR |
US$ |
1 |
Subsidy provided by HMG |
165,000 |
2,200 |
2 |
Local contribution |
60,000 |
800 |
3 |
External contribution |
851,374 |
11,352 |
|
Total project cost |
1,076,374 |
14,352 |
CHAPTER 7: Conclusions
Description
of Work |
Unit |
Rate |
Quantity |
Amount
(NR) |
Remarks |
|
A |
Civil
Work |
|
|
|
|
|
1 |
Intake and
Diversion |
|
|
LS |
10,000.00 |
|
2 |
Headrace
(100 mm diameter GI) |
Rm |
350 |
50 |
17,500.00 |
|
3 |
MS trash
rack |
No |
1250 |
1 |
2,000.00 |
|
4 |
Forebay
cum de-silting basin |
|
|
LS |
15,000.00 |
|
5 |
Flushing
set pipe arrangement |
set |
3000 |
1 |
3,000.00 |
|
6 |
Flush
valve 2” with nipple |
set |
2000 |
1 |
2,000.00 |
|
7 |
MS trash
rack |
set |
2000 |
1 |
2,000.00 |
|
8 |
Powerhouse
(3.5 x 2.5 x 2.5) in stone, mud, mortar with CGI sheet roofing |
|
|
1 |
30,000.00 |
|
9 |
Tailrace
canal |
|
|
LS |
5,000.00 |
|
|
Subtotal (A) |
|
|
|
86,500.00 |
|
B |
Electro-mechanical |
|
|
|
|
|
1 |
Penstock
pipe |
|
|
|
|
|
2 |
100 mm
diameter 10 kg/cm2 HDPE penstock |
Rm |
425 |
110 |
46,750.00 |
|
3 |
GI vent
pipe |
Rm |
150 |
1.5 |
225.00 |
|
4 |
Bell mouth
with HDP flange set |
set |
2500 |
1 |
2,500.00 |
|
5 |
Pipe
coupling flange set |
set |
1000 |
1 |
1,000.00 |
|
6 |
Medium
head single jet Peltric set including ballast for induction generator |
set |
125,000 |
1 |
125,000.00 |
|
7 |
16 sq mm
armored pvc copper cables for inter-connection and for up to first pole |
Rm |
175 |
30 |
5,250.00 |
|
8 |
Earthing
sets including 300 x 300 x 3 mm copper plate, 4 sq mm copper conductor |
set |
1500 |
5 |
5,250.00 |
|
9 |
Lightning
arresters (0.22 kV) |
No |
2 |
1500 |
3,000.00 |
|
10 |
Tools (hot
plate, Teflon cloth, thermochalk, steel wool, line tester, pliers,
screwdriver, Giti wrench, slide wrench, pocket multimeter |
set |
6000 |
1 |
6,000 |
|
11 |
Spares (control
transformer, bearing, mcb) |
|
|
LS |
5,000.00 |
|
12 |
Weasel
ACSR conductor |
Rm |
20 |
3,600 |
72,000.00 |
|
13 |
Shackle
insulators with D iron and mounting accessories |
No |
85 |
70 |
5,950.00 |
|
14 |
Stay sets |
set |
1200 |
5 |
6,000.00 |
|
15 |
Wooden
junction boxes (approx.) |
set |
125 |
70 |
8,750.00 |
|
16 |
Load limit
switches in lockable metal box (approx.) |
set |
600 |
10 |
6,000.00 |
|
17 |
Service
drop cable |
Rm |
20 |
300 |
6,000.00 |
|
18 |
Main
switch |
set |
2000 |
1 |
2,000.00 |
|
19 |
Local
wooden poles |
No |
500 |
70 |
35,000.00 |
Local
contribution |
20 |
7/22
service wire |
Rm |
10 |
4500 |
45,000.00 |
|
21 |
Household
wiring (64 hh + school + gomba) |
No |
66 |
3000 |
198,000 |
|
|
Subtotal (B) |
|
|
|
|
|
C |
Transport
of materials by helicopter |
kg |
45 |
1500 |
67,500.00 |
|
D |
Installation
|
|
|
LS |
75,000.00 |
|
E |
Survey
and design |
|
|
LS |
66,000.00 |
|
F |
Supervision |
|
|
LS |
50,000 |
|
G |
Subtotal (D + E + F) |
|
|
|
191,000.00 |
|
H |
Total (A + B + C + G) |
|
|
|
931,925.00 |
|
I |
VAT
(10% of H) |
|
|
|
93,192.50 |
|
J |
Total (H + I) |
|
|
|
1,025,117.50 |
|
K |
Contingencies
(5% of J) |
|
|
|
51,255.88 |
|
|
Grand Total (J + K) |
|
|
|
1,076,373.38 |
|