The documents required in the construction of hydroelectric power in Indonesia

Did you know?

How many documents are needed for the construction of mini-hydro power plant in Indonesia?

The documents required in the construction of hydroelectric power in Indonesia, quite a lot and cumbersome and therefore has not seen government efforts to accelerate the utilization of renewable energy.

1. Principles of forestry land use permit from the Ministry of Forestry.
2. Principle permit replacement of land forest from the Ministry of Forestry.
3. Official recommendation of the Energy and Mineral Resources. (Provincial level).
4. Recommendations from the Governor
5. Principle permit the use of land forest (from the Province).
6. Permit principle of Regents.
7. Utilization and land use permits (IPPT)
8. Principle permit the use of land forest from the Regent.
9. Building permit (IMB)

And many more documents are needed.

Application of micro hydro power plant in Indonesia

By Ahmad Suhendra

Scheme "on the grid" is less attractive to investors because the electrical energy produced by microhydro or minihidro power plant valued more cheaply by PLN (in Java Rp 432/kWh) than the electrical energy produced by other sources (eg fossil) , resulting in payback period becomes longer than 5 years. Also invested too risky, because the rate of environmental degradation (forest), which is high at 1.08 million hectares per year that could threaten the availability of water for the survival of micro hydropower plant so that the old design is not achieved. For the scheme "off the grid" there are still opportunities for investors because they do not have to sell electricity to PLN, but directly to consumers, particularly for rural areas that are not grid.

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Wind Turbines

This book is concerned with the subject of wind energy, as source of clean and renewable and free for all. The need for this type of book is very well documented, the current consumption of energy is unsustainable and humans have to change their habits and or utilise this source, but there is so much work before we can rely completely an renewable energy. This book aims to describe the fundamentals of wind energy and the pertinent parameters that control the amount of energy available from given win turbine.

Wind Turbines
(c) 2010 T.Al-Shemmeri & Ventus Publishing ApS
ISBN 978-87-7681-692-6

Benchmark prices in the Framework of Power Purchase Accelerating Indonesia's Energy Diversification

The benchmark prices of the Power Purchase are as follows :

(According to the Minister of Energy and Mineral Resources Regulation No. 044 of 2006)
Prices are stated in U.S. dollars

• 4. 95 U.S. cents / kWh for capacity to 25 MW per-unit;
• 4.75 U.S. cents / kWh for capacity > 25 MW sd 150 MW per-unit;
• 4.50 U.S. cents / kWh for capacity > 150 MW per-unit.

Or prices set by the Electricity Basic Tariff (Tarif Dasar Listrik/TDL)

• 70% of TDL to capacity to 25 MW per-unit;
• 65% of TDL to capacity> 25 MW to 150 MW per-unit;
• 60% of TDL to capacity> 150 MW per-unit.

Note:

Power purchase price may change if there is agreement between both parties regarding changes to the indicator, inflation, factors generating capacity, and coal prices.

Conclusion:

1. Purchase price of electricity set by the Government is the highest benchmark price.
2. While the amount of the contract is an agreement of both parties according to the mechanism of Bussiness to Bussiness.
3. The benchmark price setting process is "bottom-up", which is based on the proposal of PT. PLN (Persero).
4. Power purchase price adjustment is possible, as long as agreed by both parties and stated in the contract of sale of electricity.

Download Electricity Basic Tariff 2010 (Tarif Dasar Listrik/TDL)

Ref :
http://www.elektroindonesia.com/seminar/20080814/dirjen-lpe.pdf

GUIDELINES FOR BUSINESS ELECTRICITY IN INDONESIA

For those of you who will do business power in Indonesia for a small or medium then you should know the basic laws and regulations that exist in Indonesia.

Photo by Departemen Energi dan Sumber Daya Mineral

News of the Republic of Indonesia No: 46 of 2009
MINISTER OF ENERGY AND MINERAL RESOURCES
REPUBLIC OF INDONESIA NUMBER: 05 OF 2009

Business guide for small-scale Power Generation and spread in Indonesia
MINISTER OF ENERGY AND MINERAL RESOURCES
NO: 1122 K/30/MEM/2002
June 12, 2002

Micro Pelton Turbines E.Book

If you want to make micro Pelton turbines , then you must read this e-book as a reference. This publication (e-book ) has its origin in a workshop on "Micro hydro power energy", organized by GATE, which was held in Eschbom, Germany. The aim of the workshop was to discuss relevant experience in planning and implementation of very small hydro power plants in developing countries, to determine problems and deficits in the technical and socioeconomic fields and to discuss masters on direct utilization of mechanical power. One of the deficits stated at this workshop concerned micro Pelton turbine installations.

Niederuzwil, September 1991
Markus Eisenring

Read E.Book

Saddles, supporting blocks and expansion joints

By Ahmad Suhendra

The saddles are designed to support the weight of the penstock full of water, but not to resist significant longitudinal forces. The vertical component of the weight to be supported, in kN, has a value of :

F1 = (Wp + Ww) * L Cos θ
where :
Wp = weight of pipe per meter (kN/m)
Ww = weight of water per meter of pipe (kN/m)
L = length of pipe between mid points of each span (m)
θ = Angle of pipe with horizontal

The design of support rings is based on the elastic theory of thin cylindrical shells. The pipe shell is subject to beam and hoop stresses, and the loads are transmitted to the support ring by shear. If penstocks are continuously supported at a number of points, the bending moment at any point of penstock may be calculated assuming that it is a continuous beam, and using the corresponding equation. The rings are welded to the pipe shell with two full length fillet welds and are tied together with diaphragm plates.

The span between supports L is determined by the value of the maximum permissible deflection L/65000. Therefore the maximum length between supports is given by the equation:

L= 182.61 * [(Dp + 0.0147)^4 - Dp^4)]^(1/3) / (Wp + Ww)

Example :
What is The vertical component of the weight to be supported if such data is given below:

1.Diameter of pipe (Dp) = 0.636 m
2.Pipe thickness (e) = 0.005 m (5 mm)
3.Density of pipe (ρ steel) =7.9 ton/m^3
4.Density of water (ρ water) = 1 ton/m^3
5.Angle of pipe with horizontal (θ )= 5 deg


I. Wp (weight of pipe per meter)
= phi * ( Dp + e) * e * ρ steel
= 3.14 (0.636 + 0.005)* 0.005 * 7.9
= 0.079 ton/m

II. Ww (weight of water per meter of pipe)
= [(phi x ( Dp^2) / 4] * ρ water
= [(3.14 x 0.636^2)/4] * 1
= 0.32 ton /m

III. Total weight (Wp + Ww)
= 0.399 ton/m (Wtotal)
= 0.399 * 9.81
= 3.914 kN/m

IV. The maximum length between supports.
L= 182.61 * [(Dp + 0.0147)^4 - Dp^4)]^(1/3) / (Wp + Ww)
= 182.61 * [(0.636 + 0.0147)^4 - 0.636^4]^(1/3) / (3.914)
= 182.61 * [0. 01566 ]^(1/3) / (3.914)
= 182.61 *[0.2502]/3.914
= 11.67 m

V. The vertical component of the weight to be supported.
F1 = (Wp + Ww) * L Cos θ
=3.914 kN/m * 11.67 m* Cos 5
= 45.503 kN

Ref :
ESHA (European Small Hydropower Association),”Layman’s Handbook on How To Develop a Small Hydro Site,”2nd ed, 1998 http://www.scribd.com/doc/8885765/Layman-Handbook-for-hydro-electric-power-plants

Photo
http://www.fr.aps-sales.com/documentos/downloads/HydroPower%20and%20penstock%20applications.pdf

Sebintang River (0 36 22.4N ; 113 02 41.7E) in West Borneo, Indonesia

The Choice of Materials For Water Turbines

Photo by Ahmad Suhendra

Determination of material for water turbine is very important, because turbines work on conditions such as high pressure, abrasion caused by sand carried by the flow, and also of pH levels and salinity that can cause corrosion, so that the appropriate materials needed to treat the condition. There are several types of water turbines and materials used in their manufacture.
Penentuan bahan untuk membuat turbin air sangatlah penting, karena turbin bekerja pada tekanan tinggi, adanya pengikisan karena pasir yang terbawa air , juga derajat keasaman (pH air) dan kadar garam dalam air yang dapat menyebabkan korosi, maka untuk itu diperlukan bahan yang tepat untuk mengatasi hal tersebut.
Disini diperlihatkan beberapa jenis turbin air dan bahan yang digunakan untuk membuatnya.

Read More

Ref:
http://www.ivt.ntnu.no/ept/fag/tep4200/innhold/The%20choice%20of%20materials.pdf

Shaft Diameter and Shaft Critical Speed

By.Ahmad Suhendra
The size of the diameter of the shaft is very influential at critical speed. If the shaft is rotating close to or exceed the critical speed, the shaft becomes very fast vibrate and cause the bearings become damaged, so the correct practice should be working below the shaft critical speed.

Example calculations.
A Pelton turbine disc has a weight of 30 kg , and planned to have a nominal rotational speed is 1500 rpm and Power = 100 kilowatts. Shaft material (solid cylinder shaft) to be used is a standard steel, with the number: AISI-SAE 1040, which has Ultimate tensile stress (UTS) 90.000 psi and Young's modulus (E) 29 10^6 psi .
What is the diameter (D,mm) of the shaft is used?
If the distance between the bearings and disc is L= 50 mm (see picture),
what is the critical rotational speed (Nc)?
Did diameter shaft that is used safely?

Given :
N = 1500 rpm
P =100 kW
m = 30 kg
UTS = 90,000 psi (620.5 N/mm^2)
E = 29*10^6 psi (199948 N/mm^2)

I.) Torsional or twisting moment (T, N.mm).
T = 9.55 10^6 P/N................................(1)
= 9.55 10^6 * 100 / 1500
= 636667 N.mm

II.) Ultimate shear stress (UST, N/mm^2).
UST = 0.75 *UTS........................................(2)
= 0.75 * 620.5
= 465 N/mm^2

The allowable stresses (Ss) that are generally used in practice are:
4000 psi ( 28 N/mm^2) for main power-transmitting shafts (Ss < UST).

III.) Polar Section Modulus (Zp, mm^3).
Zp =T / Ss............................................(3)
= 636667/28
=22738 mm^3
and,
for circular solid shaft is :
Zp = (phi D^3) / 16................................(4)
D^3 = Zp *16 /phi
= 22738 * 16 / 3.14
D = 115863^(1/3)
= 49 mm or 2 inchi. (Shaft diameter)

IV.) Polar moment of inertia (I ,mm^4) of a circular solid shaft.
I=1/4* R^4.............................................(5)
I = phi D^4 / 64
= 3.14 ( 49^4)/64
=282836 mm^4

V.) Critical speed.
shaft weight is negligible.
E =199948 N/mm^2
I=282836 mm^4
L=50 mm
m=30 kg

Nc =[ 3 * E * I / (m *L^3)]^0.5 / (2*phi)..............(6)
= [ 3 * 199948 * 282836 / (30 * 50^3)] ^0.5 / ( 6.28)
= 45242^0.5 / 6.28
=213 /6.28
=34 rev/s
=2040 rpm

Nc > N, 1500 rpm (OK, can be used safely).

N(1500) / Nc(2040) = 0.735
0.735 < 0.8 (subcritical operation)

Note:
lower than 0.8 * Critical speed - subcritical operation
higher than 1.25 * Critical speed - above critical operation


Ref:
http://www.tribology-abc.com/calculators/uts.htm
http://www.roymech.co.uk/Useful_Tables/Matter/shear_tensile.htm
http://www.engineeringtoolbox.com/torsion-shafts-d_947.html
http://www.roymech.co.uk/Useful_Tables/Drive/Shaft_Critical_Speed.html
http://jimnevins.net/Stuff/Machinery%27s%20%20handbook%2026th%20Edition/MH26/yc.pdf

An example design of the crossflow turbine, type BYS-T3

Picture : www.boutiquepower.com.au

You can use an example design of the crossflow turbine type BYS/T3 by Ueli Meier as a teaching or a comparison with the turbine you plan, if you look at and study the sample design,it will open your insights about how to design a crossflow turbine. For those just learning about the turbines may be found in many less obvious things but do not worry , a lot of reading on the internet resources that can help you to understand it. We hope you become part of people who care about the future of the planet by using renewable energy . Thanks

Read more
Ref : Ueli Meier , " Design of Crossflow Turbine BYS/T3 " , Swiss Center Appropriate Technology - Varnbuelstrasse 14 CH-9000 St.Gallen Switzerland

Resistance Coefficient ( Ke ) For Entrance

Inward projecting----Sharp edged---Slightly Rounded---Well Rounded

he = Ke * V₂ ² / (2*g)

he = Entrance losses (m)
Ke = Depends upon the shape of the intake opening
V2 = The average velocity (m/s) of water in penstock
g = Gravitational constant (9.8 m/s^2)

Ref :
ESHA (European Small Hydropower Association),”Layman’s Handbook on How To Develop a Small Hydro Site,”2nd ed, 1998 http://www.scribd.com/doc/8885765/Layman-Handbook-for-hydro-electric-power-plants

Resistance Coefficient K for Sudden Expansion-Contraction

The losses through these fitting are generally evaluated by first obtaining

ß = d2 / d1

Important Note:

the resulting K values as tabled below are based on the flow velocity in the larger pipe,

if the flow velocity in the small pipe is used to evaluate the head loss then the K values tabled below should be multiplied by 

( ß)^4 = (d2 / d1) ^4

Head loss (h):

h_expansion(he) = Ke*(v2)^2 / (2*g)

h_contraction(hc) = Kc*(v2)^2 / (2*g)

v2= Average velocity (m/s) of water in small pipe

g =  Constant of gravity 9.8 m/s^2

Table of Ke & Kc against β = d2 / d1

β	Ke	Kc
0.15	1887.42	965.43
0.2	576	300
0.25	225	120
0.3	102.23	56.17
0.35	51.31	29.24
0.4	27.56	16.41
0.45	15.51	9.72
0.5	9	6
0.55	5.32	3.81
0.6	3.16	2.47
0.65	1.87	1.62
0.7	1.08	1.06
0.75	0.6	0.69
0.8	0.32	0.44
0.85	0.15	0.27
0.9	0.06	0.14
0.95	0.01	0.06
1	0	0

Ref : http://www.roymech.co.uk/Related/Fluids/Fluids_Pipe.html

Trash rack (or screen) losses

By Ahmad Suhendra

A screen is always required at the entrance of a pressure pipe . The function of screen (trash rack) is :

• keep debris away from the entrance to the outlet works where the debris will not clog the critical portions of the structure;
  
• capture debris in such a way that relatively easy removal is possible;

The flow of water through the rack also gives rise to a head loss. Though usually small, it can be calculated by a formula due to Kirchmer .

ht = [Kt * (t / b)^(4 / 3) * (Vo ^2 * Sin α )] / (2 * g)

ht = Screen head loss (m)
Kt = Resistance coefficient
t = Bar thickness (mm)
b = Width between bars (mm)
Vo= Approach velocity (m/s)
g = Gravitational constant (9.8 m/s^2)
α = Angle of inclination from horizontal


Ref :
ESHA (European Small Hydropower Association),”Layman’s Handbook on How To Develop a Small Hydro Site,”2nd ed, 1998 http://www.scribd.com/doc/8885765/Layman-Handbook-for-hydro-electric-power-plants

http://www.knoxcounty.org/stormwater/pdfs/vol2/3-3-5%20Trash%20Racks%20and%20Safety%20Grates.pdf

The microhydro plant

By Manfred Mornhinweg (manfred@ludens.cl)

My little paradise has a stream that provides enough water flow and head to run a small turbine, to provide electricity to my home. While writing this, the microhydro plant is being implemented, and here are some photos of the process.

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Walsh River Micro-Hydro Turbine Contruction Guide

Prepared by Max Enfield, December 2007, revised March 2010

These notes are intended as a guide to those wishing the construct a Banki-crossflow turbine like that were previously available and used in the Walsh River Micro-Hydro Systems. The focus of the notes is on construction details, rather than design.

The Walsh River Micro-Hydro System derived its name from the Walsh River in Far North Queensland, where the prototype system was installed. The system concept was developed and prototyped in 1991 by Jerry Jeffress and features the integration of custom made Banki-crossflow turbines, with Baldor DC generators and AERL Hydromax DC:DC step down controllers. It can also be used to pump water, indeed it has been used to pump water and generate electricity simultaneously.

Read more

The head losses in the penstock

By Ahmad Suhendra

The various head losses which occur between reservoir and turbine are as follows:

1. Trashrack (or screen) losses

2. Entrance losses

3. Losses due to pipe friction

4. Bend losses

5. Losses in valve and fittings.

6. Losses in sudden contraction and expansion

Head loss due to installation of a trashrack
ht = [Kt* (t / b) ^ (4 / 3)* (Vo ^ 2 * Sin α)] / (2 * g)
Kt= depends upon the shape of the screen
Vo=Approach velocity (m/s)

Head loss due to entrance
he = Ke * V ^2 / (2 * g)
Ke = depends upon the shape of the intake opening
V = The average velocity of water in penstock
[Permissible velocity in Penstocks,V(m/s) =0.125 (2 g H)^0.5,
Ref : USBR (1961) (P J Bier)]

Head loss due to friction in the penstock
hf = [(10.29* n ^ 2 *Qp ^ 2) / Dp^5.333] *Lp
n = manning's roughness coefficient depends upon the type of pipe

Head loss due to the installation of the bend
hb= Kb * V^2 / (2 * g)
Kb= depends upon the shape of the bend and the condition
of the inside surface
V= The average velocity of water in penstock

Head loss due to Fitting and Valve
hv = Kv *V ^ 2 / (2 * g)
Kv= depends upon the type of fitting and valve
V= The average velocity of water in penstock

Head loss due to sudden contraction and expansion
hc = Kc *V ^ 2 / (2 * g)
Kc= depends upon the type of sudden contraction and expansion
V= The average velocity of water in small pipe(1.273 Q /Dp^2 m/s)

Total Head Loss

h_total = ht + he + hf + hb + hv + hc

Where:

• g = constant of gravity 9.8 m/s^2
• Qp = flow in penstock (m^3/s)
• Dp = inside diameter of penstock (m)
• Lp= lenght of penstock (m)
  
• k = resistance coefficient
  
• t = screen thickness (mm)
• b = width between bars (mm)
• α = angle of inclination from horizontal (deg)

Ref:

1. http://www.iaa.ncku.edu.tw/~aeromems/Mott/ch10.pdf
2. ESHA (European Small Hydropower Association),”Layman’s Handbook on How To Develop a Small Hydro Site,”2nd ed, 1998

Calculation of flood spillway

By Ahmad Suhendra

Flood spillway was designed based on the excess water and high water in the channel carrier (head race)

Example :

Flood Spillway will be made on a channel that has a water depth of 0.691 m, with a normal discharge (Q normal) of 0.6 m^3/sec. What is the length of Flood spillway?

Spillway length (L spillway) is obtained by using the equation of calculating Weir and must be able to pass through if the flow (Q spillway) in a state of excess but not based on the flood peak.

Dicharge Coefficient (Cd)
Profile of Crest Weir	μ- factor	Cd=2.953 μ
Board, sharp edge	0.49-0.51	1.44 - 1.51
Board, round edge	0.50-0.55	1.48 - 1.62
Round overfall	0.65-0.73	1.92 - 2.16
Sharp edge,	0.64	1.89
Rounded	0.75	2.21
Roof Shaped	0.79	2,33

Standard Weir equations:
Q = Cd * L weir * (h over the top )^1.5
In this case :

• L spillway = L weir
• Q spillway = Q minor flood - Q normal = Cd * L spillway * ( h over the top)^1.5

There are some values of  Discharge Coefficient  (Cd) and in this calculation the value of Cd was taken 1.6 (Board, the round edge)

Then :

• L spillway = (Q minor flood – Q normal) / (Cd * ( h over the top)^1.5 )

To increase the water on the head race taken a number of around 20% of normal conditions and is considered as a minor flood (small flood).

• Q minor flood = 1.2 * 0.6 = 0.72 m^3/sec
• h minor flood = 1.2 * h = 1.2 x 0.691 = 0.829 m
• h over the top = 0.829 - 0.691 = 0.138 m
• Q spillway = 0.72 - 0.6 = 0.12 m3/sec
• L spillway = ( 0.12) / (1.6 * 0.138 ^1.5) = 1.46 m

Loss coefficients for pipe bends are commonly used in MHP

The losses in figure as shown left , vary according to the R/D ratio and the deflection angle of the bend. An R/D ratio of six results in the lowest head loss, although only a slight decrease is indicated for R/D ratios greater than four. As the fabrication cost of a bend increases with increasing radius and length, there appears to be no economic advantage in using R/D ratios greater than five.

Ref:
BURIED STEEL PENSTOCKS SECOND EDITION 1998
Published by Construction Marketing Committee, AMERICAN IRON AND STEEL INSTITUTE
In cooperation with and editorial collaboration by STEEL PLATE FABRICATORS ASSOCIATION, INC

Generator Selection

Generators must be sized to handle their load based on the continuous KW, kilowatt load, and KVA, kilovoltamp load, and the worst case starting load KW + KVA. They must be derated for temperature and elevation. They are sized also on whether they are continuous or standby use. The following steps are used to obtain information:

Read More


ref:

• http://www.fs.fed.us/database/acad/elec/greenbook/24_generator_selection.pdf
• http://www.teachnet.ie/torourke/Physicswebsite/electromagnetism.htm

The using of Electronic Load Controller (ELC) to replace governor in MHP

By Achmad Hasan

The using of Electronic Load Controller (ELC) to replace governor in Microhydro Power Plant (MHP) can hopefully manage the enormous changing of load by giving a quick system response and lower price than governor. Because of providing power for electricity require high cost and the geographic condition of Indonesia also the unbalance spread of load, so the MHP is the most economic energy resource. MHP is the right plant for providing energy especially for remote area with a low load crowd and far from PLN (Indonesian state electricity company) network.

Read more (in the Indonesian language)

Manning coefficient (n)for several commercial pipes

By European Small Hydropower Association (ESHA)
Over the years many empirical formulae, based on accumulated experience, have been developed. They are, in general, not based on sound physical principles and even, occasionally, lack dimensional coherence, but are intuitively based on the belief that the friction on a closed full pipe is:

1. Independent of the water pressure
2. Linearly proportional to its length
3. Inversely proportional to a certain power of its diameter
4. Proportional to a certain exponent of the water velocity
5. In turbulent flows it is influenced by the wall roughness

One of these formulae, widely used to estimate the flow in open channels, but also applicable to closed pipes, is that developed by Manning

Q= (1/n)* A^(5/3)* S^(1/2)* P^(-2/3)

Where n is the Manning roughness coefficient, P is the wetted perimeter (m), A is cross-sectional area of the pipe (m^2) and S is the hydraulic gradient or head loss by linear meter.

Applying the above formulae to a full closed circular cross section pipe:
S= 10.29 n^2 * Q^2 *D^(-5.333)
S= hf / L (head loss)
hf = Head loss (m)
Q = flow in penstock (m^3/s)
D = inside diameter of penstock (m)
L= lenght of pipe
Manning coefficient n for several commercial pipes

Types of Pipe	n
Welded steel Polyethylene(PE) PVC Asbestos cement Ductile iron Cast iron Wood-stave(new) Concrete (steel forms smooth finish)	0.012 0.009 0.009 0.011 0.015 0.014 0.012 0.014

Ref : ESHA (European Small Hydropower Association),”Layman’s Handbook on How To Develop a Small Hydro Site,”2nd ed, 1998. http://www.scribd.com/doc/8885765/Layman-Handbook-for-hydro-electric-power-plants