PV Mini-Grids for Yap State Micronesia

Sustainable Design for remote Pacific Islands



The REP-5 programme “Support to the Energy Sector in 5 ACP Pacific Islands” is being implemented by the Pacific Islands Forum Secretariat supported from the 9th European Development Fund (EDF).  The programme is managed by IT Power, Transénergie and ADEME and focuses on renewable energy and energy efficiency activities. There are five countries participating in the REP-5 programme. These are the Federated States of Micronesia (FSM), Nauru, Niue, Palau and the Republic of the Marshall Islands (RMI). A Programme Management Unit (PMU) for the REP-5 programme was established in January 2006. The PMU has its main office in Suva, Fiji with a sub-office in Pohnpei, FSM.  In the Federated States of Micronesia energy is the responsibility of each of the 4 states, therefore the state governments are also closely involved in the implementation of projects under the REP-5 programme. The four FSM states are Chuuk, Kosrae, Pohnpei and Yap. This paper concerns the activities of the REP-5 Programme in Yap State, FSM.





REP-5 objectives


The five pacific countries targeted in the REP-5 programme are all characterised as Small Island Developing States (SIDS). Their development challenges are particular, compared to other developing


countries, given their very small populations,  their isolation  in the          Girls wearing traditional dress inYap

Pacific Ocean,their relatively small GDP per capita and their fragile environment. Given this context, the overall objective of the programme is poverty alleviation by improving access to electricity, and thus improving the living conditions in the targeted Pacific island states. In FSM and RMI, the REP-5 programme is focusing on increasing access of outer island population to adequate, affordable and environmentally sound electricity to facilitate socio-economic improvements. In Nauru, Palau and Niue the focus is on improving the overall efficiency of the energy sector through demand-side energy efficiency measures and, where justified, increasing production through renewable energy sources. Efficiency improvements can be expected to reduce the countries’ energy bill, thus contributing to fiscal balance.


The Federated States of Micronesia


Like many other island nations, the Federated States of Micronesia (FSM) is heavily dependent on petroleum as a source of energy. The import of fossil fuel alone accounts for over 30 % of FSM’s national budget, and as world oil prices continue to spiral upward while the global supply dwindles and demand gains, this number will only get higher.  The need and priority for the FSM now is to explore every means possible to broaden the energy mix so that renewable forms of energy become more prevalent in the coming years. In April 2006 the consumer fuel cost of a kilowatt-hour (kWh) of electricity on Pohnpei, the FSM’s largest island was 17.5 cents, up 80% from 9.74 cents in September 2002.  With added fuel surcharges, the Pohnpei Utility Corporation (PUC) charges consumers a combined total of 40 cents per kWh in January 2008, and it is now approaching 50 cents.  The other state Utilities – Kosrae Utility Authority (KUA), Chuuk Public Utility Corporation (CPUC) and Yap State Public Service Corporation (YSPSC) – face similar spiralling rates due to the high cost of fossil fuel.

These rising fossil fuel costs and consumption not only affect the government, but also businesses, individuals, and families as the FSM and the Micronesian region continue to experience skyrocketing energy costs. Access to consistent, affordable, renewable energy is vital for achieving the national sustainable development goals, laid out in the Federated States of Micronesia Sustainable Development Plan (FSM SDP, 2004).

Pohnpei Harbour

A reduction of the burning of fossil fuel, which leads directly to the emission of greenhouse gasses, which in turn lead to the severe weather patterns, rising temperatures and tides that are having an apparent and immediate effect on the 607 islands of the FSM, will also set a clear and present example for the rest of the world’s industrialized nations.  The FSM sits at the forefront of the effects of climate change.

The FSM sees an opportunity now, through the REP-5 programme to begin to build a sustainable renewable energy framework that will allow its utilities to continue to transition, expand services (46% of households currently do not have access to electricity) and prosper and ease the mounting burden of payments that families and villages must shoulder (particularly those at the lowest income levels).



The FSM will consciously seek to include and build the private sector as it relates to renewable energy technologies, maintenance, and installation, and will look to renewable to reduce the fuel expenditures and costs for the national and state governments.

Solar and hydro energy are perhaps the two main renewable energy sources available in the FSM. Solar energy is available in all the states, with hydro resources available only in Kosrae and Pohnpei. 

Coconuts are also a good source of biofuel and this has a great potential to be supported and expanded.


Copra collection in Mwoakilloa                       According to the Coconut Development Authority, the FSM is producingaround 600 to 900 tonnes of copra per year (compared to 5,000 to 8,000 tonnes in the 80s) and most of it is produced in the outer islands.   Further, as some preliminary field tests indicate, there appears to be potential for small-scale production of bio-gas from methane.  Throughout the FSM, owning pigs is a big part of the culture and pig pens are nearly ubiquitous, especially for Kosrae and Pohnpei. A truck in Pohnpei running on coconut-oil

Hurdles and challenges persist however.  With transport to the outer islands, high fuel costs and changing weather patterns chief amongst them.  A more sustainable use of locally available sources of energy, along with the priority of the nation to achieve equitable and improved living standards, will require that these challenges be met.


REP-5 activities in FSM


The list of selected projects that will be financed under the REP-5 programme where selected by the Programme Management Unit in close cooperation with the various State Utilities, State Agencies and National Government Departments. The main selected renewable energy and energy efficiency projects and activities in the 4 States are presented in the table below.


Country - State


FSM      -     Chuuk

Outer islands of Onoun, Moch, Satawan and Udot: electrification of schools and health centres by solar PV mini-grid

-          Kosrae

5 grid-connected PV systems: The State capitol building; Kosrae international airport; the hospital; KUA; the high school library

-          Pohnpei

Outer islands of Mwoakilloa, Pingelap, Kapingamarangi, Sapwuafik  and Nukuoro: electrification of schools and health centres by solar PV systems

-          Yap

Ulithi atoll islands of Fadrai and Asor: electrification of schools, health centres and households by PV solar mini-grid

-          Federal

Portable solar lanterns, PV Capacity Building and Energy Efficiency


Economic and social impact


The indigenous population of the FSM is Micronesian with most of the people residing on the main islands of the State capitals. The 2000 census preliminary count of the population was 107,000 (July, 2000). Traditional, social and cultural institutions are still very strong in Micronesia. Micronesian society is based on the extended family, which is responsible for the family and community welfare, especially in relation to land. 

Palikir, Pohnpei: One of the National Government Buildings

Both men and women share equal and distinct responsibilities in terms of the management of the family and the lands.

The economy of the FSM is relatively small with aggregate GDP in current prices of approx. US$200 million in 1999, implying a per capita income of US 2,030.00 (FSM NBSAP Report, 2002).  Out of some 29,000 employed persons in 2000, 15,000 persons (52%) were engaged in farming and fishing, of whom over 10,000 (70%) were involved in 'subsistence' (household consumption only) activities, not selling or intending to sell any of their produce. Almost 5,000 (30%) were classified as 'market-oriented' farmers and fishermen. These numbers illustrate the importance of the subsistence sector in the FSM and reflect their contribution to domestic production in the country (FSM Statistical Yearbook 2005).  It can be assumed by these numbers also that much of the economic activity is not properly captured and goes unreported.

Outer islands remain mostly in a traditional subsistence and barter economy and the source of incomes includes copra, handicrafts, local food products and remittance from relatives in the working economy. Most of the urban centres of the nation – Totol (Kosrae State Capital); Kolonia (Pohnpei State Capital), Colonia (Yap State Capital) and Weno (Chuuk State Capital) - can be considered as nearly full participants in the money economy. Although by conventional poverty definitions, rural residents are often considered impoverished, there is strong evidence that the average quality of life as well as length of life is often better on rural islands than in the more urbanized centres.  Relative poverty, where there are problems in meeting basic human needs, is more common in urban areas than rural areas of the FSM. 

The remoteness of the FSM limits economic opportunities and creates a high cost of living resulting from costly shipment of imported commodities. The implementation of the 9th EDF REP-5 programme as well as the next 10th EDF and other RE initiatives, is anticipated to relieve parts of these limitations by cushioning the impact of fuel price increases mainly in the provision of an affordable and reliable supply of electricity to improve both the social and economic outlook for the population.


Yap State – PV mini grid


Yap is the most intriguing island state in Micronesia. It is a land steeped in ancient traditions, fascinating legends, and peopled by one of the most distinctive cultures in the Pacific.


Picture Left: YapTraditional-Curtural Dance  / Picture Right: Traditional boat in Yap                                    

This traditional life carries on in the villages where fishing, sailing and weaving are still important parts of everyday life. Grass skirts for the women and thu'us, a type of loincloth, for the men are the basic garb in the small towns that sit in tranquil settings around the island. The outer islands of Yap are very remote and can only be reached by boats or by a small plane which flies only twice a month and only if there are sufficient passengers. In Yap State of the FSM, REP-5 programme will implement two remote island PV mini-grid systems.


General Design


The local project manager is the Yap power utility, YSPSC. The two solar powered mini-grids will be installed on islets in Ulithi atoll. The two islets being electrified are Fadrai with 31 houses and Asor with 18 houses. Both also have several public facilities. All the houses and buildings will be connected to the mini-grid and YSPSC will install pre-payment meters for every connection.

The North Pacific follows the US standards on electricity and thus an AC 120V 50 Hz system is used in all the FSM States and AC 120V equipment is regularly available. However, in order to minimize the power loss in the distribution system and the chance of consumers connecting high energy consuming equipment, the PV systems will deliver 230VAC at 60Hz. Users that have appliances that require conversion to the Yap standard of 120V will be required to use a transformer connected to the appliance.  

Since YSPSC operates a diesel powered mini-grid on two islets (Mogmog and Falapap), both also located in Ulithi atoll, the household appliance loading found on these islands can be expected to also develop on Fadrai and Asor.  Almost all households on Mogmog and Falalap have a video system and between 80% and 90% have a refrigerator or freezer.


Computor Lab in an Outer Island school

Portable fans are common and of course electrical lighting is universal. Based on the premise that the Fadrai and Asor households will follow those of Mogmog in appliance use, an estimate of the anticipated energy and power needs of the households on Fadrai that can be expected to develop over the five years following electrification was prepared. It is crucial to educate the households in the conservation of energy so that they actively participate in demand side management (DSM) when using their appliances. Since YSPSC intends to include pre-payment meters and to charge a rate commensurate with the real cost of power on outer islands, if users are educated in the efficient use of electrical energy, waste is likely to be minimal.


During normal use of the power system, even during evening peaks the watt loading can be expected to be substantially lower than the assumed maximum in the system design (which is essentially the load if all appliances are on simultaneously). However, the design takes into account the case of a power system restart after a power outage at a peak time, when all refrigerators and freezers as well as other appliances that are  turned on would start simultaneously.


The inverter sizing needs to be sufficient to accommodate that initial demand. Therefore the system has an inverter size which is sufficient to meet the full appliance demand.

Initial discussions were to have all installations use Australian standards for power (230V 50Hz) and power points also are to be of the Australian type so users cannot directly plug in US standard appliances and cause them damage or be a safety hazard. The later decision by YSPSC is to use 230V but at 60Hz so that locally purchased refrigerators and other equipment can operate under normal conditions when connected through a transformer, the same method is used by them in Mogmog and Falapap.

All lights installed are to be Edison base CFL type fluorescent bulbs with integrated high efficiency electronic ballasts. The household load is based on the use of 13W 230V high efficiency CFL lights since (a) 9 to 11 W lights have been shown to be acceptable for outer islanders and their use is common in the Pacific for rural lighting; and (b) reducing the lighting load allows the released capacity to be used for higher priority appliances namely video systems and refrigerators.


Because the 230V CFL bulbs are not readily available on Yap, YSPSC has agreed to stock appropriate replacement bulbs on the islets. Therefore, the proposed approach for lighting is to equip houses with 13W type CFLs that cannot easily be replaced with higher wattage incandescent bulbs or higher wattage CFLs while still providing adequate light and long life. In each house, the dispensary and in offices, each fixture will have its own switch. In school classrooms, one switch will control a maximum of two fixtures and switches shall not be grouped together but will be positioned on the wall near the fixtures they control. Wiring for classrooms, dispensary consultation room and email/computer rooms will include a connection and control wiring for one ceiling fan in each room. Sufficient power points will be provided in all buildings to operate the expected appliances as based on interviews with users of the buildings.


Besides the household load, public facilities also will be electrified. These include a dispensary, school, church, administrative offices and the men and women’s buildings. The total forecast energy requirement for the public buildings is 8.8 kWh/day during the time when school is in session in Fadrai and 8.2 kWh/day in Asor.

Picture left above: Fradrai - Picture above: Asor

The total forecast energy for Fadrai is 94.7 kWh/day while Asor has a total forecast of 35.6 kWh/day.

Due to budget constrains it was impossible to comply with the expected load needs. To electrify the island within the budget that was allocated for Yap State would mean that households would not be allowed to purchase videos or refrigerators, only lights and fans. This is a constraint that is unlikely to be accepted by all users and overloading of the system due to at least some households adding other appliances is considered to be almost impossible to prevent. Since with a solar PV mini-grid system overloading leads to frequent power outages due to discharged batteries and ultimately to an early failure of the batteries and since a primary goal of the project is to meet the needs of the rural population for electricity for quality of life improvements and productive use, it was clear that the project cannot be considered a success if those needs are not being met.


With the budgetary restrictions and with strict energy efficiency and conservation measures in effect, only around 20% of the households can in fact have those needs met. With this information in mind a critical examination of the overall FSM budget was carried out and any funds that were not essential to the other FSM projects were shifted to increase the hardware capacity of this project since it has the best chance of long term success provided the capacity is sufficient to meet the villager’s needs for electricity. Thus additional capacity to allow at least some use of videos and refrigerators, on an extended family or other multi-household basis, was made available to ensure that the system will function reliably for more than a short time. Following this adjustment, up to 40% of households can include a refrigerator and video – sufficient to probably allow at least each extended family to have access to these appliances.

Due to the remoteness of the system and the difficulty of providing maintenance, repair services and spare parts, the design focused on simplicity and high component quality. Further, the system needs to operate in the difficult environment of a tropical atoll which includes high ambient temperatures, high humidity and exposure to air with high salt content. Transport will be using locally available boats which limits the size and weight of individual components in particular batteries and cabling.

Power will be delivered at 230VAC to avoid the complexity, cost and power losses of distribution transformers. This is the approach that has been successfully used on Mogmog and is consistent with YSPSC practice on outer islands. A three-phase distribution (with full sized neutral) will be used in order to keep cable costs to a minimum while still allowing the PV system to be divided into three individual sections that will allow the battery

 cell size to be reasonable without requiring parallel connected cells.      Underground Cables: huricane proof


The energy requirement of each of the three phases will need to be reasonably well balanced to ensure that each of the three battery banks will be properly sharing the load. It is noted that for the PV system, the phase balancing needs to be for daily energy use in kWh, not power demand in kW as is the case for rotating generation equipment. The YSPSC also will use pre-payment type meters as is their policy for outer island electrification. This is considered an important component of the system for promoting energy efficiency and though the meters represent a substantial parasitic load for the system, their use is strongly recommended, as only through consistent revenue collection from the consumers can the systems be truly sustainable in the long-term.

Both sites will have a ground mounted array and a small power house to enclose the batteries, controls and inverter will be constructed. The power house will be constructed under the array thereby both ensuring that the power house will be in the shade and also keeping power losses between the array and the battery bank minimal.

YSPSC will maintain the systems and will stock up on spare-parts (like inverters and batteries), and electrical appliances like CFL light bulbs, low energy consumption electrical fans, radios, TVs, etc. on the islands. The community will be assisted to create an electrical supply committee which will ensure that the number of refrigerators and video systems are limited to about one third of the households, presumably with those facilities shared among extended family members so that all members of the community have reasonable access. This will avoid over-usage of the planned system.

The total budget allocated for the PV systems is €450,000 and another €250,000 for site preparation, cables, transportation and installation. About 15% of the amount of the PV system is allocated for training, supervision for installation and commissioning. The total capacity for the two mini-grids is 46.53 kWp. Fadrai will have 216 130Wp modules and a battery bank of 2884 Ah that consist of C10 rated 2V single cells; while Asor will get 145 130Wp PV modules and a 1854 Ah battery bank. The PV mini-grids are expected to be installed between September and October 2008.