Engineers Without Borders – UW-Madison: Micro-Hydroelectric Power, Rural Electrification, and Bayonnais, Haiti
Jonathan M. Lee Electrical Engineering Department University of Wisconsin – Madison Submitted for EPD 397 Instructor: Dr. L. Grossenbacher December 12th, 2008
Table of Contents
Executive Summary............................................................................................................... 3 Introduction............................................................................................................................ 4
A Traditional Hydroelectric Facility ..................................................................................... 5 The Peligre Hydroelectric Dam ................................................................................. 5 A Run-of-River Hydroelectric Facility.................................................................................. 7 Structural Overview................................................................................................... 7 Electrical Details........................................................................................................ 8 Micro-hydro Case Study Analysis: Nepal ........................................................................... 12 Conclusions and Recommendations .................................................................................... 14 Appendix: Haiti’s Electricity Environment ......................................................................... 15 Glossary ............................................................................................................................... 16 References............................................................................................................................ 18
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Executive Summary An ordinary Haitian does not have electricity and only 10% of the country has access to this resource (Aguilera, 2004; Sontag & Polgreen, 2004). Access doesn’t necessarily mean that the service is used. It only means that electrical distribution lines are in the near vicinity. Increasing access and use of this service in Haitian is very important, and will no doubt play a part in assisting the poorest nation in the western hemisphere out of their current abysmal state. Haiti has the natural resources to increase this access dramatically. One single technology will not be a cure-all, and large-scale energy infrastructure creation is not a sure bet to bring greater access. Many approaches to finding solutions in this kind of environment are available, and Engineers Without Borders believes the approach is to work with one village at a time. Specifically, EWB-UW-Madison (EWB-UW) wishes to construct a 15 kW micro-hydroelectric power plant in Bayonnais, Haiti to provide electricity to a future clinic. This project will increase access to electricity in the microhydro distribution area substantially, but if this access is looked at through a national lens, the increase in access it will provide to Haiti will be negligible at best. With this situation in mind, a question can be asked: Is micro-hydro appropriate for Haiti? Haiti is familiar with large traditional hydroelectric dams like the Peligre Dam, which mostly, for management reasons, serves its country by being a fantastic concrete wall. This dam in the long run has turned out to be inappropriate for Haiti. Micro-hydro in a run-of-river configuration, on the other hand, will not block the flow of a river, and excludes the environmental and local population impacts resulting from a large dam. Additionally, Haiti’s natural resources give the possibility for increased hydroelectric development. Many micro-hydro facilities can be placed on a single river, increasing the possibility of generating power close to load centers (villages) near these rivers. From this technical (and mostly structural) point of view, micro-hydro is indeed appropriate for Haiti. Although this claim might be the case, EWB-UW must still take care to make their project appropriate for Bayonnais. They must think not only about the technical equipment, but also about the environmental components, quality aspects, and maintenance issues. The EWB-UW project aims to work on the problems of a very small area. Even so, there are many details to this small project. What should EWB-UW know about micro-hydro? First, a run-of-river setup, which only diverts river water, is the most appropriate and fitting structure for a small community at this power level. One drawback might be the potential for inconsistent power if drought conditions are present. Second, due to its robust operating characteristics, an induction generator should be used for electricity generation. Additionally, the transmission line system should be at least a 1 kV, single phase (two wire), grounded system. This will increase the potential electricity distribution area of the project. Finally, an electronic load controller should be used because it will keep the load power consumption constant for the generator. This aspect is desirable because it will maximize the micro-hydro’s electricity output.
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Introduction The Engineers Without Borders – UW-Madison Haiti Group (EWB-UW) proposed in September 2008 to build a micro-hydroelectric generating facility to power a yet-to-be-built clinic in the village of Bayonnais, Haiti. A micro-hydro facility is a power plant that produces power in the 5kW to 100kW range (Practical Action, 2004). Currently, neither an electric system nor a health care system exists in Bayonnais. Although EWB-UW’s work is focused on powering this health care facility, it has chosen a technology that may have the potential to be used more broadly in a Haitian rural electrification program. Electricity is high on the list of desirable resources not only in Bayonnais, but also in the rest of this small Caribbean nation. Only 10% of the population of Haiti, the poorest country in the Western Hemisphere, has access to electricity (Aguilera, 2004; Sontag & Polgreen, 2004). “Those who have access received on average 10 hours of electricity a day in the last two years, with very large disparities among the areas covered” (The World Bank, 2006). World Bank reports show that the government-owned utility, Electricité d’Haïti (EDH), has an installed capacity of 221MW for the entire country, with an additional 74MW being produced by Independent Power Producers (IPPs). An IPP is a third party generating facility that sells its power to the local (in this case, government) utility (Central America Management Unit, 2006). To better understand the potential role of micro-hydro within the Haitian electric industry, an examination of the electric industry within the country has been included in the appendix. In EWB-UW’s case, they will be working within the country, but outside of the national electric grid. EWB-UW’s work focuses on the issue of powering a new clinic in Bayonnais. This clinic is greatly needed. Furthermore, throughout Haiti, healthcare can only be described as awful. Haiti has the highest mortality rate for children younger than five, and the highest death rate for infants and women giving birth in the Western Hemisphere (Lacey, 2008, Sept. 13th). HIV and tuberculosis rates [in Haiti] are by far the highest in the hemisphere. This dismal situation is encouraged by the lack of medical professionals in Haiti. “There are 1.2 doctors, 1.3 nurses, and 0.04 dentists per 10,000 Haitians; 40 percent of the population is without access to any form of primary health care” (Farmer, 2005). In poor areas of the world, all problems seem to overlap. In EWB’s case, energy and health are working hand-in-hand. EWB-UW hopes to address, in a small way, this issue of health in Bayonnais by supplying power to this new clinic. Broadly, micro-hydro may be a part of the answer in providing power to not only clinics, but also Haitian homes and businesses. Haiti has the water resources that justify the construction of many micro-hydro power plants. The US Army Corps of Engineers assessed Haiti’s water resources in 1999. They found that there were 30 hydrographic (‘water catchment’ or ‘river’) basins in the country, which drained from the mountains to the coasts. Many of these mountain streams were found to have a branching network of tributaries (Knowles, Buckalew, Markley, Roebuck, 1999). People who live nearest to the country’s rivers would be the
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primary beneficiaries of a micro-hydro energy infrastructure due to the cost of electricity transmission. Additionally, for communities near water resources, micro-hydro may be the most applicable solution, but micro-hydro should not be used without an analysis of its positive and negative aspects. First, a framework should be setup to understand micro-hydro’s place within the electricity industry in Haiti. To understand how this electricity industry works, Haitian electricity project reports from both the World Bank and the InterAmerican Development Bank were studied. An analysis of this information was placed in the appendix of this report. Also, concerns revolving around the effects of hydroelectric dams are discussed. Two types of hydroelectric structures were studied: traditional and run-of-river facilities. The Peligre Dam, a traditional dam in central Haiti, was studied. Then, a run-of-river structural overview and electrical detail were contrasted with the traditional setup. Due to length concerns, a mechanical detail was excluded from this report. The last part of the report describes a case study of micro-hydro use and rural electrification in Nepal. Here, the construction aspects, mostly concerning rural electrification and electricity transmission, are discussed. Based on the analysis of microhydro systems, and a review of their implementation, conclusions are drawn about how micro-hydro can be best implemented in Haiti. Finally, suggestions are also made for the EWB-UW project regarding the most effective model for the system they wish to create. Traditional Hydroelectric Facility A traditional hydroelectric facility is defined as a structure that uses a dam to block a river, allowing a large reservoir, or lake, to form behind it. This reservoir provides the potential energy for the power plant. Immense pipes move this water through turbine-generator combinations, which change kinetic energy into electricity. In Haiti, the Peligre Dam is the most infamous traditional hydro facility. This dam promised many great things, but has failed to live up to its advertized gifts. The Peligre Hydroelectric Dam The Peligre Dam (Figures 1-3) is the largest hydro facility in Haiti. Ideally, this power plant generates 50MW, but it is rarely in good condition (IADB, 2006). It is a traditional hydroelectric structure that impedes the Artibonite River – Haiti’s largest river – creating a vast reservoir out of a fertile valley. “The Army Corps of Engineers planned the Peligre Dam. Brown & Root of Texas, among others, built the structure during the reign of one of Haiti’s American supported dictators, with money from the U.S. ExportImport Bank.” The dam was intended to provide power to agri-businesses, mostly American-owned, 50km southwest in the capital, Port-au-Prince, during the 1950’s, but its consequences for the farmers who would be displaced from the valley was not taken into account (Kidder, Mountains beyond Mountains, 2003, p.37). The Peligre Dam has the ability to produce great amounts of energy. Its downside is its need for vast amounts of land to accomplish this task. A traditional dam effects a local population negatively if the needs of the community are ignored.
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Figure 1. A photo of the Peligre Dam, Haiti’s largest hydroelectric facility. Behind the dam is Lac de Peligre, the reservoir formed after its completion. The reservoir displaced thousands of Haitians who lived near the river (Wikipedia, 2007). The farmers in this valley lost their former lives over night. “By all the standard measures, the “water refugees” became exceedingly poor; the older people often blame their poverty on the massive [Peligre] dam a few miles away, bitterly noting that it brought them neither electricity nor water.” The local population retreated to the hills surrounding the valley, which were stony and not meant for farming. Many of these people later found work in the capital of Port-au-Prince, the main benefactor of the dam’s electricity, as servants (Farmer, Pathologies of Power, 2005, p. 32). Most of the Haitians displaced by the dam were not reimbursed for their land. In fact, most still don’t have drinking water or electricity, even though the dam was built for those purposes (Kidder, Mountains Beyond Mountains, 2003, p37). Traditional hydroelectric facilities can have adverse effects on the environment and population of the reservoir’s flood plain. Future hydroelectric facilities built in Haiti might bring fear to the local population that another Peligre Dam might be built. During the design and construction of the Peligre Dam, environmental and population factors were not taken into account.
Figures 2 & 3. Aerial views of the Peligre Dam. The photo to the left emphasizes the vastness of the reservoir that was created by the Peligre Dam. The photo to the right is a closer aerial view of the Dam (Google Maps, 2008).
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Although fears like this could surround future projects, designs exist that minimize the impact of the power plant on the environment and surrounding population. The most prevalent impact-minimizing design is called a run-of-river structure. Run-of-River Hydroelectric Facility Micro-hydro is most appropriate when it offers low environmental impact on the area where it is built. A run-of-river design accomplishes this requirement. Additionally, the electrical components of the system will be discussed. These components are independent of the structural style of the micro-hydro facility. Below a structural overview of a run-of-river project is presented. Structural Overview The structural components of a run-of-river system, because they are large, have a non-ignorable impact on the surrounding areas. Long segments of pipe, concrete channels, and imposing structures near the river changes the community. If this work is not well guided, these structures may define how the community perceives the project.
Figure 4. A drawing of a run-of-river hydroelectric facility. The drawing notes all of the structural components of the run-of-river system (Appropedia, 2007). The first two structures of a run-of-river hydro are meant to collect and condition the water at the input of the system. First, the intake weir (Figure 4) assists in diverting a part of the river into the micro-hydro system. The weir is a slim, rectangular concrete slab placed into the river. A small amount of water will pool behind this structure once it is set, but this quantity is not a significant amount. The next structure, the settling basin, takes advantage of this pooling and blocking effect that the intake weir produces. The water, which has now been blocked by the intake weir, will have an area where large debris can sink to the bottom (May, Nicholas P. B., 1982). This settling basin is the first defense for a system that wants to keep its input as debris-free as possible. This basin must be cleaned at regular intervals.
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After the water moves through the settling basin, it needs to be carried to the powerhouse by a set of aqueducts, channels, and pipes collectively called the intake structure. Structural designers must understand these three options very well because of issues regarding constructability. Pipes can be placed above or below ground, but must be maintained effectively. Valves are needed in certain areas to relieve water pressure, and inspections are needed to check the pipes for leaks. Channels, which can be open-air or sealed, can be used in some areas where pipes may not work well. Usually, these channels are rectangular box structures made out of concrete. An open-air channel can be used strategically in the waterline to provide an area where maintenance crews can clear debris or access multiple points in the line (May, Nicholas P. B., 1982). These structures guide water to the intake structure tank. The intake structure tank, also called a forebay tank or a spring box, allows water to settle. If there is too much water input into the system, excess will be diverted here. The intake structure tank looks like a large box without a top. It is made of concrete with rebar reinforcement. Water that initially enters the tank will either be diverted back to the river or to the penstock. The penstock connects the intake structure tank to the powerhouse. The design engineers can build the penstock to be able to input a certain amount of water from the intake structure tank. A valve also controls how much water can be diverted. The height dimension from the input of the penstock to the base of the penstock is called the head (Practical Action, 2004). The head, along with the density of water, flow rate, and gravitational acceleration, is used in power calculations, which assist the design engineers in sizing the powerhouse. This powerhouse contains the mechanical and electrical components that generate electricity. These components include a turbine and a generator. The kinetic energy of the water will be transformed into mechanical energy by spinning the turbine. The turbine is connected, either directly or through a belt system, to the generator. The generator will then transform the mechanical energy into electrical energy, which then flows to the transmission lines. After the process of energy conversion, the water will exit the powerhouse via the tailrace. The tailrace is the channel constructed to allow the flow of water from the powerhouse to the river (May, Nicholas P. B., 1982). A run-of-river system only diverts a river’s water for a distance equal to the length of its structure. This property defines the most important way in which this structure minimizes its impact on both the environment and local population. Electrical Details The micro-hydro facility will solely exist to produce power. Therefore, the equipment for generation, transmission, and control must be chosen wisely. Each of the three areas just mentioned has two primary, competing technologies, which need to be understood in detail. For generating electricity, an induction generator or a permanent magnet generator is used. To transmit the electricity, two different construction schemes are used: overhead line or buried line cabling. Finally, control devices must be present in the system. For this control, an electric load controller or a hydraulic governor is used. An electrical system is most appropriate for an area when it is composed of high quality,
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maintainable components. The components ultimately chosen must show this characteristic. The generator is the muscle of the electrical system. It is where the power is generated. There are two options regarding this generator for a micro-hydro system: induction or permanent magnet generators. These two systems are viable for different power ranges. An induction generator (Figure 5) is the much cheaper alternative below 50 kW. An induction generator is a machine that generates electricity through rotating a metallic cylinder in a magnetic field that produces power at varying rotor speeds. After this value, the permanent magnet generator becomes more cost competitive with the induction generator. A permanent magnet generator’s rotor is composed of a solid, cylindrical magnet. In terms of reliability, the induction motor is more robust. It can withstand higher over-voltages, -currents, and -speeds. Additionally, they are built for work in continuously rotating conditions (Smith, 1994). In contrast, the permanent magnet generator may not be able to withstand the same magnitude of these quantities that the induction generator can withstand.
Figure 5. A computer model of an induction generator. The cut-away section shows the rotor and stator components. The large cylinder in the center of the rotor is a magnet, which induces currents in the copper coils of the stator, when rotated. The transmission system will carry the energy to the consumers. Depending on what type of loads will be powered the transmission system can either be three- or singlephase power. Three phase power uses four wires – three for power and one for ground – and normally is used when the load contains large motors. Three-phase power decreases vibrations in these motors. If the load is composed mostly of lights, single-phase transmission – using one wire for power and one for ground – can be used (Glover, 2002). This transmission system can either be placed on poles (overhead lines) or in the ground (buried cables). Typical power transmission and distribution in the United States is conducted on overhead lines. These wires are usually bare aluminum conductors. Overhead line systems are prone to having specific reoccurring problems. First and foremost, overhead lines are extremely susceptible to storms. High winds, downed trees, ice, and extreme heat are just some of the conditions that will strain or break the overhead lines or the
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poles propping them up (Al-Khalidi, H., 2006). In Haiti, these storms are ever present in the hurricane season. For EWB-UW, hurricane-proofing the micro-hydro facility may be the best option to increase technical sustainability. Secondly, overhead lines are constrained to relatively open areas. When homes on narrow streets are close together, overhead lines may not be able to fit anywhere near the homes they are intended to service (Mackey, 1990). Finally, the ability to span obstacles is one advantage of overhead lines. Ravines and cliffs for example may pose problems for buried cables, but for overhead lines these are easy obstacles to cross (Al-Khalidi, H., 2006). Overhead lines are a traditional form of transmission, but in Haiti, due to the hurricane season, a transmission system completely composed of overhead lines may not be the most appropriate. Buried cables may provide a solution to this problem. Buried cables solve some problems present in overhead line system, but aren’t perfect. Although the likeliness that a storm will take down segments of the transmission system is decreased when buried cables are used, mudslides and soil erosion due to storms can still break or unearth segments of the buried lines (Al-Khalidi, H., 2006). Buried cables have fewer faults than overhead lines (Xcel Energy, 2000). A fault is when an electrical line at a given potential instantly becomes a different (usually zero) potential. An example of a fault is when a tree branch falls, breaks a transmission line, and this line hits the earth, thus changing from a line potential (say 1 kV) to a ground potential (0 kV), which can result in very high currents that can damage components. The downside of buried cables is an initial cost greater than the initial cost of overhead lines. Larger earth-moving equipment is needed to build the trench for underground lines (Mackey, 1990). Buried cables, because of their decreased exposure to the elements, may be more appropriate for the situation in Haiti. EWB-UW must weigh the cost differences, and efficiently design the transmission system to use both overhead lines and underground cables where appropriate. A high quality, easily maintainable system is the goal of many engineering projects. To obtain a high quality micro-hydro system, there must be a control system. The control systems must be setup to analyze the voltage and frequency of the generator and change the system accordingly. This information is needed to control how the generator is operating in relation to how the load is changing. In power systems work, the energy used by these consumers is called the load. It is therefore very important to know what devices will be used to control the system. Historically, only two types of systems have been used: hydraulic governors and electric load controllers. A hydraulic governor controls the flow of water into the powerhouse. It does this by the use of movable metal barriers within the pipes, which are controlled by hydraulic arms. The governor is connected to both the structural system (the pipes) and the electrical system. The governor is set to sense voltage changes on the transmission lines. When these changes fall below or climb above a certain level, the governor will set the hydraulic system in motion to partially or fully close the water flow in the pipes. As the flow of water is abated, the speed of the generator’s rotor decreases. This results in a decrease in the voltage and frequency. This process can also be reversed to increase voltage and frequency on the lines. These governors have proven to be slow and
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inaccurate. They are mechanically constrained to how much or how little they can control the system (May, Nicholas P. B., 1982). For instance, water flow can only be increased by a certain amount (the width of the pipe), and if additional water is needed to spin the turbine faster, the hydraulic governor will not be able to control the system to produce this result.
Figure 6. An example electronic load controller. Both the generator voltage and current are measured. Caution lights for over-frequency, under-frequency, and overpower are labeled. To obtain higher precision, an electronic load controller (ELC) is used. In contrast to the hydraulic governor, this system (Figure 6) is only needs to connect to the electrical system. It does not abate the motion of the water in the pipes. This controller senses both the voltage and frequency of the transmission lines. Its main goal is to keep the electrical demand on the generator constant. As consumer demand decreases, other loads, lumped together and known as the dump load, are turned on and serve as a temporary load (Smith, 1995). A good example of this change in consumer demand can be imagined when people go to bed and turn their lights off. Here, the load from the lights diminishes, the ELC senses this, and switches in additional loads to take the place of this one. This allows the power generation to be kept at a constant rate.
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Micro-hydro Case Study Analysis: Nepal Although topological differences exist between Haiti and Nepal in terms of altitude variations present in their river basins, a qualitative comparison is possible. In terms of water catchment basins, both Nepal and Haiti are quite similar. Nepal has 36 hydrographic basins, and Haiti, again, has 30 basins (Kansakar, Hannah, & Rees, 2002). Unlike Haiti, Nepal, since 1980, has been aggressively pursuing the use of microhydropower. The result of this investment has been the installation of 1,956 micro-hydro turbines generating just over 13MW of electricity (ITDG, 2001). Using a simple comparison, this power is enough to power 26,000 homes each using 500W of power. A similar micro-hydro initiative might be appropriate for Haiti as well. In Nepal, micro-hydro was successful because financial support, government policy, local manufacturing, and external technical assistance were present and actively applied (ITDG, 2001). Financial support from government was applied in the form of subsides for expensive equipment and state credit (Cromwell, 1991). Additionally, a favorable policy environment was set in place. Micro-hydro electrification was featured prominently in all the Five-Year Plans of Nepal after 1980. Targets for micro-hydro were set at 5MW in two of these plans (ITDG, 2001). Along with this financial support, Nepalese planners working along side non-governmental organizations slowly installed a network that has become thousands of micro-hydro turbines large. A support structure of Nepalese manufacturers who service this industry has also been created. NGOs can provide technical assistance from an external source. These organizations provide a jumpstart in knowledge. They usually have links to government and research resources not available in the project country. With the instantaneous availability of knowledge and designs, technical projects like a micro-hydro facility can begin quickly (Cromwell, 1991). In countries such as Nepal and Haiti, NGOs can do their part to start additional technical projects with their initial assistance and investment. Take for example the Andhikhola hydro facility.
The Andhikhola hydro facility is a grid-connected, 5MW rural electrification project in central Nepal. Although the focus of this paper is on off-grid, micro-hydro facilities and not grid-connected, small-hydro facilities, this example is quite illustrative, and will assist the EWB-UW project. First, the Andhikhola facility was constructed with an induction generator for reasons of robustness, over-speed protection, and voltage regulation. This seems to be a typical application of this technology in this setting. Second, the distribution system of this project contained many useful features. Aluminum conductor steel-reinforced (ACSR) wires, sized to give 10% maximum voltage drop, were used for transmission. Additionally, insulated – or covered – wires were used. This decision increased safety and decreased theft in the system. The 1 kV distribution system was the real innovation in this project (Figure 7 & 8). Typical rural electrification in Nepal used 400 V lines for a maximum distribution of 1 km in radius. In contrast, the 1 kV lines gave a 5 km radius. This increased the possible distribution area by 25 times (Mackey 1990). Analyzing Nepal’s micro-hydro projects can provide a wealth of technical information to micro-hydro facility planners like EWB-UW. Although this may
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be true, Nepal’s success with micro-hydro was not due solely to the availability of technical information. It was only one part of a more comprehensive planning process.
Figure 7. An aerial one-line diagram view of the Andhikhola power system. The total radial distance of the 1 kV transmission line is almost 4 km. It has a theoretical radial distance of 5 km.
Figure 8. The power system schematic of the Andhikhola electrical network. The 1 kV distribution line was the real innovation, increasing the distribution area over 25 times the distance achievable with the traditional Nepalese 400 V distribution system.
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Conclusions and Recommendations Far too many Haitians do not have access to electricity even though Haiti has the natural resources to increase this access dramatically. In truth, Haiti’s problems are vast and have plagued the country for decades. One single technology will not be a cure-all, and large-scale energy infrastructure creation is not a sure bet to surgically add a prosthesis to either eastern or western arm of the country. Many approaches to finding solutions in this kind of environment are available, and Engineers Without Borders believes in working toward answers one village at a time. EWB-UW wishes to construct a 15 kW micro-hydroelectric power plant in Bayonnais, Haiti to provide electricity to a future clinic. This project will increase access to electricity substantially in the microhydro distribution area, but if this access is looked at through a national lens, the increase in access it will provide to Haiti will be negligible at best. With this situation in mind, a question can be asked: Is micro-hydro appropriate for Haiti? Haiti is familiar with large traditional hydroelectric dams like the Peligre Dam, which mostly, for management reasons, serves its country by being a fantastic concrete wall. This dam in the long run has turned out to be inappropriate for Haiti. Micro-hydro in a run-of-river configuration, on the other hand, will not block the flow of a river, and excludes the environmental and local population impacts due to a large dam. Additionally, Haiti’s natural resources give the possibility for increased hydroelectric development. Many micro-hydro facilities can be placed on a single river, increasing the possibility of generating power close to load centers (villages) near these rivers. From this technical (and mostly structural) point of view, micro-hydro is indeed appropriate for Haiti. As a note, if the Haitian government did wish to pursue expanding electricity to its citizens through the use of micro-hydro, it would be wise to learn from Nepal. An energy infrastructure investment needs to coordinate government, industry, financial, and non-governmental organizations. Incentives must be correctly setup, technical support must be delegated, and government backing must be implemented through policy. It is a very large undertaking. In contrast, the EWB-UW project aims to work on the problems of a very small area. Even so, there are many details to this small project. What should EWB know about micro-hydro? First, a run-of-river setup is the most appropriate and fitting structure for a small community at this power level. One drawback might be the potential for inconsistent power if drought conditions are present. Second, due to its robust operating characteristics, an induction generator should be used for electricity generation. Additionally, the transmission line system should be at least a 1 kV, single phase (two wire), grounded system. This will increase the potential electricity distribution area of the project. Finally, an electronic load controller should be used because it will keep the load power consumption constant for the generator. This aspect is desirable because it will maximize the micro-hydro’s electricity output.
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Appendix: Haiti’s Electricity Environment The government owns a majority of the electric industry in Haiti. Electricité d’Haïti (EDH) created in 1971 as an autonomous government agency owns and operates most of country’s electricity generation, and all of the transmission, distribution, and retailing. EDH is managed by The Ministry of Public Works, Transport, and Telecommunications (MTPTC), which designs policies and regulates the country’s electric industry. EDH is technically bankrupt, and it needs government funding from the Ministry of Economic Affairs and Finance (MEF) to operate. Seven percent of the national budget is appropriated for EDH. “Haiti’s electricity service is in crisis. In its current state, EDH is neither technically nor economically viable; it is unable to maintain its generating capacity, or to reduce electricity losses to reasonable levels. As a consequence, while EDH charges high average rates (close to US¢20/kWh), it does not generate the income needed to satisfy current demand under reasonable conditions and expand service” (IADB, 2006). To say the least, EDH has many problems. EDH is unable to provide sufficient and reliable electricity to its consumers on its poor distribution network. This is a result of the technical issues at generating facilities owned by EDH (The World Bank, 2006). Of this installed capacity, which has been prone to quality and reliability problems, 207MW is directly connected to the capital, Port-au-Prince, a city of 1.8 million people. This leaves the remainder of the population, 6.9 million, with a theoretical access to an installed capacity of only 88MW, or 12.75 watts per person of electricity. This per person amount is about one sixth of the power needed to turn on a traditional incandescent, 60W light bulb (Central America Management Unit, 2006). In addition to the power deficiency, some institutions will not collaborate with the Haitian government. The World Bank currently will not develop any electrification (including rural) projects with EDH. “The possibility to develop an electrification project with EDH or with other providers was rejected given that EDH is not even able to service those consumers that are in covered areas, mostly in Port au Prince.” (The World Bank, 2006) It also seems that the Haitian government takes the same attitude toward its electrification as the World Bank does. The Haitian government does not sponsor any electrification programs in the country. This leaves a large hole for outside non-governmental organizations and nonprofits to fill. These organizations, like EWB, mostly work with small community-base institutions like schools and churches. Small electrification programs for these communities can be formed to fulfill the need for electricity, which the Haitian government has failed to manage effectively. Electrification programs managed at the community level, separate from the nation’s electric grid, can be based around many forms of generation. Solar, biomass, water, or fossil fuels are the usual energy sources. The electricity industry in Haiti is a complete mess. Comprehensive electric sector planning failed to work, and currently is not being pursued. Efforts to find solutions to the Haitian electrification problem seemed to have died out, and the former players who might be able to fix the whole thing have left the table.
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Glossary ACSR – a type of electrical distribution wire, which stands for aluminum conductor steelreinforced Aqueduct – a structure that takes water over valleys and other obstacles Bayonnais – the Haitian village working with EWB-UW to build the micro-hydro project Electric d’Haiti – the government-owned electric utility of Haiti Electronic Load Controller – a device that measures voltage and frequency of the transmission system and generator, which varies the loads to keep the power demand on the generator constant Engineers Without Borders – a non-profit organization designed to teach student engineers how to be internationally responsible global citizens and to build appropriate, sustainable infrastructure in developing communities Fault - a fault is when an electrical line at a given potential instantly becomes a different (usually zero) potential Forebay Tank – a rectangular concrete box that acts as the juction between the intake structure, the penstock, and the diverting channel Haiti – a country located on the island of Hispaniola in the Caribbean Head – the height from the top to the bottom of the penstock. This value is used in power calculations. Hydraulic Governor – a mechanical device that measures voltage change and decreases or increases water flow to try to keep the voltage constant Hydrographic – a water catchment or river basin Independent Power Producers – a privately owned producer of power that sells its energy to the grid owner, in Haiti’s case EDH Intake Weir – a structure that diverts water from a river to the hydroelectric structure Induction Generator – a machine that generates electricity through rotating a metallic cylinder in a magnetic field that can produce power at varying rotor speeds Micro-hydro – an electricity produced facility that generates power in the range of 5kW to 100kW
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Permanent Magnet Generator – a machine that rotates a cylinder made of a solid magnet to generate a rotating magnetic field and produce electricity Penstock – the piping that allows water to flow from the forebay tank to the powerhouse. The difference in height from the top to the bottom of the penstock is known as the head. Powerhouse – the powerhouse is the structure that contains the turbine and generator Rural Electrification – the building of electricity infrastructure away from cities Run-of-River Dam – a water-diverting structure that funnels water off of a river and directs it to a turbine-generator combination located in a powerhouse Tailrace – the channel that allows water to flow from the powerhouse back to the river Traditional Dam – a large, concrete, water-impeding structure, which forms a reservoir
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References Aguilera, A. (2004). Bank’s Transition Strategy. Inter-American Development Bank. Appropedia. (2008). Retrieved Nov. 18th, 2008 from http://www.appropedia.org/Microhydro_power Cabraal, R., Barnes, D.F., & Agarwal, S.G. (2005). Productive Uses of Energy For Rural Development. Energy Sector Management Assistance Program, The World Bank Central America Management Unit. (2006). Electricity Loss Reduction Project (Report no. 36364-HT). The World Bank Farmer, Paul. (2005). Pathologies of Power. Partners in Health. Glover, J., Sarma, M. (2002). Power System Analysis and Design. Brooks/Cole Publishing Google Maps. (2008). Retrieved Nov. 18th, 2008 from maps.google.com Khennas, S., Barnett, A. (2000). Best practices for sustainable development of micro hydropower in developing countries. Department for International Development, UK. Kidder, T. (2003). Mountains Beyond Mountains. Random House Publishing Knowles, R., Buckalew, J., Markley, B., Roebuck, L. (1999). Haiti Water Resources Assessment. US Army Corps of Engineers Lacey, M. (2008, September 13). Children in Servitude, the Poorest of Haiti’s Poor. New York Times. Intermediate Technology Development Group (ITDG). Sustainable Energy for Poverty Reduction. The Schumacher Centre for Technology Development Intermediate Technology Development Group (ITDG). Micro-hydro Data of Nepal. The Schumacher Centre for Technology Development Practical Action. (2004). Micro-hydro Power. The Schumacher Centre for Technology Development Penche, C. (1998). Layman’s Guidebook On How to Develop a Small Hydro Site. Commission of the European Communities, Directorate-General for Energy by European Small Hydropower Association (ESHA)
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Peru Country Department. (1999). Poverty and Social Developments in Peru 1994-1997 (Report no. 19651). The World Bank Retrace Electronics. (2008). Retrieved Dec. 6th, 2008 from http://www.retraceelectronics.com/ELC.jpg Smith, N. (1994). Motors as Generators for Micro-hydro Power. Intermediate Technology Development Group, UK. Sontag, D., Polgreen, L. (2004, October 16). Storm-Battered Haiti's Endless Crises Deepen. New York Times. Var Speed Hydro. (2008). Retrieved Dec. 5th, 2008 from http://www.varspeedhydro.com/images/induction5.jpg Wikipedia. (2007, June 25). Retrieved Nov. 18th, 2008, from en.wikipedia.org/wiki/Peligre_Hydroelectric_Dam Xcel Energy. (2000). Underground vs. Overhead Transmission Lines.
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