SITE ASSESSMENT REPORT

MICRO-HYDROPOWER PROJECT FOR

KAMPONG SRI STAMANG IIBATANG AI, SARAWAK

Site Assessment Report

SITE ASSESSMENT REPORTFOR THE DEVELOPMENT OF MICRO-HYDRO SYSTEMKG. SRI STAMANG II, BATANG AI, SARAWAK

1 General

Name of site 1: Sg. Berakit of Sg. Stamang, Batang Ai, Sarawak

for MINISTRY OF SCIENCE, TECHNOLOGY AND INNOVATION

bySIRIM BERHAD

May 2009

Date of site visit: 27/04/09 to 29/04/09

1.1 Study team SIRIM

Name1 Azhar Mohamad2 Mohamad Abdul Kadir Johari3 Fakaruddin4 Judee anak akaw5 Kasvenda Kassim6 Pandi Ahmad

LOCAL COMMUNITY

Name1 Tuai Rumah2 Wesley3 Roger4 Others (about 10)

1.2 Location of village / load centre

Village name: Sri Stamang IICoordinates (GPS reading)

Easting ( E W): 111o 56.660’ Northing ( N S): 01o 18.708’

Sub District: Batang AiDistrict: Lubok AntuState/Province: Sarawak

Key Plan of Sri Stamang 2

1.3 Accessibility to the Location

Overland from Kuching via Serian and Engkilili to Batang Ai dam of about 275km from Kuching (or 3 – 4 hrs drive). Travel by long boat for about one hour from the lake jetty to the mouth of Stamang river and travel through rapid for another half hour to the Sri Stamang II long house. The long house is situated on the right bank of the river.

2 Sri Stamang II Long House

Sri Stamang II Long House is located at the right bank of the Sg. Stamang. The Long house consists of 43 number of unit which houses 43 numbers of households. The long house is constructed on concrete foundation, concrete structure, brickwall and steel decking roof.

Village Layout

Long House

Community Service Hall

Diesel Generator House

Rice ThresherHouse

Guest Toilet

Community Clinics &House

Sg. Stamang

The longhouse at a distance The open corridor outside the Rawai

Typical House Unit Layout

3 Existing Electricity Supply

Currently the electricity supply for the long house is provided by an existing diesel engine generator running on diesel fuel which is housed in the powerhouse located near to the long house.

Family Lounge

Rawai

Lounge

Kitchen

Bedroom

Bath

Toilet

20 ft.

80 ft

20 ft

Open Corridor

The capacity of the diesel set is at 15KW and it is daily operated for only three hours running from 6.30pm to 9.30pm and unable to run at full capacity. The fuel for the diesel set and individual genset has to be transported by boat over long distance and the sets have to be regularly maintained. The electricity generated is mostly use for the purpose of lighting.

Some villagers however augmented their electricity need by running their own genset and it is indicated under such circumstances their total expense for providing their electricity need is around RM100 per month.

At the other side of the river, the community clinics consist of four residential units and a block of clinic building. Currently the clinic has its own electricity supply, running on it own diesel set.

Diesel generator set powerhouse The clinic and residential quarters

4 Demand Appraisal

The power demand is required to provide base load and peak load requirement for the need of the long house, the clinic complex and also there is a request for power requirement for the nearby school about two kilometer from the long house. There is also future demand for productive uses.

Recently the community was given by the authority one unit of rice thresher machine. The machine however is supposed to run on genset supplied to the community. The power requirement for such thresher is around 2.5 – 4.0kW.

Per Household

Type of load Power per appliance (W)

No. of Unit

Total power (W)

Remark

Lighting Type 1 25 4 100 Bulb type at bedrooms, Bath & toilet

Lighting Type 2 40 4 160 Florescence type at Rawai,Lounges and kitchen

Radio 20 1 20TV 60 1 60Fan 40 2 80Fridge 80 1 80Total 500No of HH @ longhouse 43No of HH @ Clinic 4Total # of HH 47Total 23.5K

WUnder full exposure of load

The actual peak load requirement is to be computed through power modeling at the Feasibility Study stage.

5 Preliminary Site Assessment

The main issues that should be considered in a preliminary investigation are:

5.1 The existence of a suitable waterfall or weir and a turbine site Site inspection was carried out with the assistance of the village elders and villagers. A suitable site based on waterfall on a cascade is identified and preliminary assessment was carried out.

Location;

The GPS locator indicates the location as: Easting ( E W): 111o 56.864’ Northing ( N S): 01o 18.229’

Upper level waterfall, fall height about 16m Lower level cascade fall height about 15m

5.2 Consistent flow of water at a usable rate

The Sg. Berakit river stream which could provide the flow

Flow measurement;

In situ measurement using velocity area streamflow method was carried out for the river stream. In the velocity-area method, stream velocity and water depth measurements are taken along a transect perpendicular to the stream. Total discharge (Q) is calculated by integrating the stream velocities with the cross sectional area of the stream profile defined by the transect.

Discharge, or the volume of water flowing in a stream over a set interval of time, can be determined with the equation:

Q = AV,

where Q is discharge (volume/unit time-e.g. m3/second, also called cumecs), A is the cross-sectional area of the stream (e.g. m2), and V is the average velocity (e.g. m/s).

Stream water velocity is typically measured using a current meter. Current meters generally consist of a propeller or a horizontal wheel with small, cone-shaped cups attached to it which fill with water and turn the wheel when placed in flowing water.

The value of flow is measured and computed at 0.060m3/sec. However it should be noted that this value is one of the value of the flow and does not represent the true flow parameters of the river unless such measurement is taken regularly at fixed interval over time, let say for more than a year.

However for preliminary assessment such figure could be use as a guide, bearing in mind, from the information given by the villager that heavy rain (2 hours duration) did occur one week before the measurement is made.

5.3 The likely acceptability of diverting water to a turbine

The possible configuration of the hydro system is as follows;

The water from the river main course can be diverted by raising the water level by the weir. The diverted water enters the intake and flow through low pressure conduit to a surgetank if necessary. The level of the surgetank is somewhat about the same level of the weir with the provision of gradient for the low pressure pipe. Water from the surgetank than moves down the penstock and reaches the turbine at the powerhouse at a pressure, thus turning the hydro turbine.

5.4 Suitable site access for construction equipment

The current access to the site is by walk path made by the villagers to get to their rice planting areas. The path is not suitable for access to the site in view of it steep incline and very narrow. The route follows the ridges of the hill and at steep hillside.

A new route for access needs to be made in order for construction vehicles and equipment to reach the side. These new road must take consideration of having the proper incline and width. This new access may be longer in distance

Upper waterfall

Lower waterfall

Weir, ponding and intake

Surgetank

HDPE Penstock

Low pressureconduit

Power station

Easy access is required for not only during construction period but also for operation and maintenance. Experience indicates that difficult access may lead to poor operation and maintenance. The new access will also act as the route for the transmission line. The new access proposed is about 1.3km in length.

The current walking path is made through difficult terrain

5.5 A nearby demand for electricity, or the prospect of a grid connection at reasonable cost

Current walking path

Proposed road access

Currently there is another settlement about 3.0km on the right bank (on the same side as the Sri Stamang II long house). There is a school complex at this village and the villagers informed that the school needs electricity. However the requirement of the nearby settlement including the school needs to be assessed.

However the nearby village may have a separate hydro resource which needs to be identified.

5.6 The social and environmental impact on the local area

Generally, micro-hydro project has very low environmental impact especially of run-of-river type. However the socio-economical benefits may be tremendous. The proposed micro-hydro will replace the existing polluting diesel engine set in term of air and noise pollution. The electricity could provide refrigeration of foods, thus surplus food and food raw materials could be kept for longer period and not wasted.

5.7 Land ownership and/or the prospect of securing or leasing land for the scheme at a reasonable cost

The installation of the power system, the weir, intake, low pressure conduit, surge tank, penstock and the powerhouse are normally sited along the river corridor or the river reserve. Examination at the site, the position and the alignment is within the forested reserve and do not involve individual title. However the proposed access road and transmission line, customary or individual land titles may be involved. However it should be noted that such provision of road access will be a plus to such inaccessible lands.

5.8 An initial indication of design power and annual energy outputThe accuracy of the information may only be plus or minus 25%, however, this should be sufficient for deciding whether to proceed to a more detailed feasibility study.

Simplified equation of calculating power for a particular hydro scheme at the assessment stage can be as follows;

Power P (in kW) = 7 x Flow (Q in m3/sec) x Head (H in meter)

For the project above, the flow obtain by measurement based on velocity area method is 0.06m3/sec

The gross head obtain by using the GPS altimeter is 40m (the different between the reading at the proposed weir and the location of the powerhouse)

P = 7 x 0.06 x 40P = 16.8kW

However it should be noted that the water flow is not always constant at the measured figure of 0.06m3/sec. It is important to determine the firm flow and the Flow Duration Curve of the river.

The total energy generated of the proposed project depends on the capacity factor of the plant. The nature of isolated load indicates low utilization in the daytime but peaking in the early evening.

However the above calculated figure is sufficient to warrant feasibility study to be carried out.

5.9 Estimated preliminary project cost

Based on the configuration of the proposed micro-hydro power project the following cost preliminary cost estimate for 17kW plant;

Project Costs and Savings        Initial Costs        Resource Assessment 1.02 $ 10,000

  Feasibility study 3.07 $ 30,00

0

  Development 12.79 $ 125,00

0

  Engineering 8.19 $ 80,00

0

  RE equipment 18.34 $ 179,14

7

  Balance of plant 41.71 $ 407,50

0

  Miscellaneous 14.87 $ 145,32

4

  Initial Costs - Total 100.0% $ 976,9

71

The cost of the civil and structural work is estimated at RM400, 000 representing 41.7% of the project cost. This cost however will increase only marginally as the size of the project increases. Project cost per kW = RM57,000

Assume that the project capacity is increased to 30kW;

Project Costs and Savings        Initial Costs        Resource Assessment 0.87 $ 10,000   Feasibility study 2.61 $ 30,000   Development 10.86 $ 125,000   Engineering 6.95 $ 80,000   RE equipment 28.54 $ 328,435   Balance of plant 35.41 $ 407,500   Miscellaneous 14.77 $ 169,957

  Initial Costs - Total 100.0% $ 1,150,89

2

There is no increase in the civil and structural cost but the percentage goes down to 35.4%. Project cost per kW = RM38, 000

5.10 Conclusion and recommendations

The above assessment carried out is preliminary and further study need to be carried out to ascertain the viability and feasibility of the project. From the assessment, the project is technically feasible where by putting the micro-hydro plant in place; it is possible to meet the power and energy requirement of the longhouse and replacing the power and energy supplied by the current diesel engine generation mode. Further configuring and evaluating other alternatives, the technical solution of the project can be further optimized.

The financial viability of the project required further study and refinement of all the parameters and factors.

The socio-economic benefit in term or EIRR (economic return) required further study.

It is thus recommended that a feasibility study be carried out so as for the project could reached its full potential and benefits.