Solar Battery Charging Stations

Overview

In rural areas of developing countries many households do not have access to electricity and power their radios with dry cell batteries or use candles and kerosene lamps for domestic lighting. Some employ car batteries that are charged in stations for lighting and entertainment.

Rural Electrification by Battery Charging Stations

Battery Terminal.jpg

Battery charging stations (BCSs) can be a viable option to provide electricity in un-electrified areas and where incomes are insufficient to pay for solutions like solar home systems (SHS).

In electrified areas grid-based BCSs moreover can serve to extend access to electricity to those who have no direct connection in their home, thus profiting indirectly from the electricity infrastructure.

Charged (car) batteries in fact can provide services comparable to the upper end of the pico PV range at lower investment costs, though running costs eventually are higher.

A little electricity, like from car batteries, can considerably improve living conditions of its users. Electrically powered lamps improve domestic working conditions at night in particular for women and can also enhance studying conditions for children, not only because of the better light but also since they reduce fire hazard and do not emit noxious pollutants. Other services that are highly valued and only require a little electricity as can e.g. be delivered by car batteries are radio and tv for information and entertainment, and air circulation (fans) for basic cooling. Also mobile phones, crucial for access to modern communication, helping people in rural areas to obtain information and thus e.g. facilitating commercial operations, can easily be charged off car-batteries, though they can also be charged directly at a BCS. In order to provide such services a car battery should be recharged a few times a month.

To a small extent, electricity from charged (car) batteries can also contribute to raising incomes of small businesses and handicraft, especially in communal market towns. Shop owners, for example, can open their shops in the evenings thus not only raising their income, but also delivering an improved service to the community.

In such schemes mostly lead-acid wet cell car-, truck- and / or motorcycle batteries are used as they are most easily available on the market, either new or second hand, and as they are produced locally in some countries. While thus often the least cost option, this type of (starter) batteries cannot really stand deep discharging as normally done when used for such services, implying their capacity is decreasing over time and their effective lifespan is limited. Proper deep-cycle batteries have much better performance in such set-ups but often are hard to find and cost a lot more.

Electricity from rechargeable batteries can provide a lot more service at far lower costs than disposable dry cell batteries. They are also the environmentally friendlier option provided their eventual disposal / recycling, is properly organised, which in itself is worth doing.

The batteries are transported to the nearest grid, diesel or solar-based battery charging station where they are recharged for a fee. In addition to that fee, running cost of the system may thus include the transport costs to and from the BCS. Diesel generators can charge a limited number of batteries at a time, and service costs highly depend on diesel costs. Grid based charging stations are usually less subject to quantity restrictions and changing diesel prices, but might be located far from the rural population. Solar battery charging stations (SBCS) constructed in rural areas are an alternative solution to provide the local population with energy for basic needs and reduce the time and expenses required for travelling.

Those stations consist of:

• one or more photovoltaic panels and
• a charge controller to prevent batteries from overcharging.

The size of a SBCS and the number of Photovoltaic (PV) panels installed vary according to the anticipated energy demand and to the (average) insolation - the solar energy per unit area , which varies with latitude and (average) whether conditions

The most common modes of operation of SBCS's are.

• property of the municipality
• privately owned.

The users may pay:

• a fee per charge
• a monthly fee
• for renting a recharged battery owned by the operator.

In addition to battery charging (S)BCSs may include additional services like a shop selling solar and electric equipment.

Example "Energising Development" Mali

Mali's power grid covers only a few urban areas; over 95 % of the rural population has no access to electricity from a grid. In order to enhance living conditions of the rural population, in total 50 SBSBs were installed in 17 rural municipalities as a part of the Communal Electrification Programme ‘Électrifcation Communale’ (ELCOM) which is an element of the Local Government Support Programme (‘Programme d’Appui aux Collectivités Territoriales’ (PACT)) and forms an integral part of ‘Energising Development’ (EnDev), a German-Dutch partnership.

ELCOM’s objective is to provide access to electricity in rural areas of Mali, not only by constructing SBCSs for local people, but also by installing solar powered systems for street lighting and in key public buildings like health centres, schools and town halls

The SBCS are property of the municipality; operation is delegated to a private service provider who runs them on a fee-for-service basis. The collective fees should suffice to cover maintenance costs for the SBSC and the communal PV systems as well as the eventual replacement of system components (batteries, charge controllers, bulbs etc).

From 2008 - 2011, 50 SBCS were constructed. The municipalities contributed to the expenses in cash and in kind (labour by the villagers) with an average proportion of 10 to 20 % of the initial investment costs. The remaining costs were covered by EnDev funding.

Most of the SBCS constructed have a charging capacity of four (70 Ah) batteries per day and consist of:

• a building with recharge terminal;
• six 65 Wp PV panels ;
• a charge controller;
• equipment such as cables and fittings

Some SBCS have a double set up and can thus charge eight 70 Ah batteries per day; one has three times this set up. Between the 50 SBCSs in the programme in total 268 70 Ah batteries can be charged daily.

Furthermore, each SBCS has a separate PV system for lighting consisting of a 65 Wp panel, a charge controller, a battery and lamps for inside and outside.

ELCOM Intervention Area: Regions of Ségou and Koulikoro

Overview: Municipalities with Solar Battery Charging Stations (SBCS) Installed within the Programme

Municipality	Population (Projection 2008)	No. of SBCS	Capacity of SBCS; # of 70 Ah batteries/day			Total batteries/ day
			4	8	12
Katiéna	27,405	6	3	3	-	27
Tiélè	20,133	6	5	1	-	21
Kamiandougou	15,330	4	3	1	-	15
N'Koumandougou	12,371	4	3	1	-	15
Sobra	9,282	1	-	-	1	9
N'Gassola	5,549	2	1	1	-	9
Bellen	5,409	3	3	-	-	9
Total	95,479	26	18	7	1	105

Costs, Revenues and Operational Model

Investment Costs

A SBCS with a four-battery charging capacity costs approximately € 8.000, including the costs for the construction of the building; for the bigger SBCSs costs are roughly proportionally higher.

The Customers

The user should have a battery that can be recharged in a SBCS. Batteries are costly in relation to the income of the rural population - that mostly live below the 1$/day threshold: new 70 Ah batteries cost about 40,000 FCFA (€ 61), second hand batteries cost 10 - 15,000 FCFA (€ 15 to 23). Smaller (motorcycle)batteries can also be used, costing quite a bit less while obviously also bigger (truck) batteries can be charged at the SBCS.

The charge of a 70 Ah battery in Bamako or in regional and district centres costs roughly FCFA 500 (€ 0.8). Additional transport costs (for distances sometimes up to 100 km) can lead to a total expense of FCFA 1,000 per charge.

In order to ensure sustainable operation of the SBCS the charging cost for a 70 Ah battery was calculated at 750 FCFA which is considered a competitive price compared to pre-existing conditions (long journeys, travel costs, recharge quality).

Battery charging, be it in a conventional charging station or in a SBCS, however is expensive, both in comparison to the price of grid electricity as well as related to the target population's income.

The Operator

The private operator is responsible for the running of the SBCS and for maintenance and repair of all solar powered systems (SBCS, SI and Street lighting alike) installed through the programme. Income from the SBCS is divided in a pre-defined way between daily running costs, income of the technicians, a fee for the operator, a contribution to teh municipality budget, a fee for the management committee and a contribution to the amortisation fund - from which replacements should eventually be paid.

The management committee, established in each municipality, is responsible for supervising the operation. It consists of village representatives and is responsible for the operator renting fee, for repair of equipment and for investments. The operator participates in their meetings regularly so as to ensure a mutual control of actors involved.

From the operator’s fee repairs of all solar installations in a municipality should be paid, including spare parts if necessary and potential upgrade costs. The remaining amount is the operator's profit.

In order to be profitable the SBCS have to run at 70 - over 90 % of their maximal capacity in the case of rural Mali.

Experiences

In general, the SBCS are operating reliably; good quality components were used and . They are known and reputed among the clients for their high quality of charge, which allows battery utilisation for about two weeks (15 to 20 days, depending on the quality of the battery). The quality of charge of other BCS is usually much lower (utilisation of 2 to 5 days) as they do not apply charge controllers. Nevertheless, the advantages and potential savings on energy expenditures have to be explained to the costumers, who often only see the higher price, not considering the superior price-service ratio and the amount of money saved on transport costs. Word of mouth seems to be the most effective means of marketing.

With all the SBCS running approximately 1,100 batteries are charged per month. As a result 6,470 people currently profit from the SBSC and have access to electricity. However, the number and the capacity of the SBCS in some of the municipalities were over-estimated as the number of costumers’ remains low and the SBSC are running on approximately 35 to 40 % of their capacity on average. This is partly due to the lack of rechargeable batteries. Most of the batteries brought to the SBCS are car batteries that are not suited for delivering a steady amount of current over a longer time but the only ones which are readily available in rural areas. Many households cannot even afford to buy a car battery and others have second hand batteries which are in such a poor condition that recharging them is impossible. Many potential customers had to be rejected by the operator due to the bad state of their battery. However, even those who do not own a battery profit indirectly from charging services as they can watch TV in their neighbours’ home or have their mobile phone recharged by someone owning a battery.

The maintenance of all solar installations including communal PV systems and an acceptable level of profit for the operator is not guaranteed if the degree of capacity utilisation does not reach 60 to 70 %. Currently, only in one municipality is the revenue high enough for the operator to pay the total fee. In the other municipalities the operators meet on a monthly basis with the management committee and representatives from the town hall to discuss the repartition of the revenue. In this way it is avoided that the operator is discouraged.

Almost all municipalities have had large difficulties in mobilising their share. This led to major delays in the construction of the SBCS as the communal contribution had to be paid directly to the construction companies. The municipalities, who were also the contracting authority, were unwilling to put the construction companies under pressure to terminate the construction as they were depending on the goodwill of the contracted companies to pre-finance the communal share. These dependencies sometimes resulted in less transparent awarding of contracts to construction enterprises. In addition, the inhabitants of the municipalities could not be easily mobilised to contribute their manual support for construction.

A positive development of the programme is that the private operators have begun to install solar home systems, sell solar lanterns and provide after-sales services in the rural municipalities that go beyond the original ELCOM intervention.

Lessons Learnt

The in kind contribution by the village community will be not included any more and more emphasis will be placed on a direct financial contribution. It was difficult to mobilise the whole community to perform their allocated tasks and resulted in an unfair distribution of work among the inhabitants.

Monthly monitoring of SBCS management during the first months of operation is absolutely necessary. The technicians as well as the operators need support to use the provided management tools.

Technical monitoring has to be done about every two months during the first six months to demonstrate presence and prevent misuse of the equipment installed. It also helps in capacity building regarding end-users, operators and technicians. For technical monitoring it will be necessary to develop a maintenance plan that operators can follow when they visit the installations.

In order to avoid over-capacity and reduce costs for both, the project and the municipalities, the number of SBCS, their capacity and the selection of the villages where they will be located, will be based on the result of detailed feasibility studies which will take place in the intervention area in the future. In order to ensure business profitability, wealthier municipalities should be selected where people have the means to buy quality batteries and charge them on a regular basis. Small commercial centres where electricity is required for productive use, are also better suited. Other factors such as network coverage for mobile phones and TV signal coverage have also to be taken into consideration. This experience shows the difficulty in providing electricity to the poorest and the necessity of having customers which have a certain level of income to assure the sustainability of the intervention.

Example Cambodia

A handful of solar battery stations (or rather solar assisted or with diesel generators as back up) are in place in Cambodia:

• Kamworks piloted a SBC station at an already existing battery charging station, yet stopped after half a year as the operator was not satisfied- the timing was not ideal as the project started in the rainy season, when solar irradiation is not sufficient.Also, the donated solar panels did not reach electricity generation expectations.
• 4 SBCS have been 100% funded through the GEF Small Grants Programme under UNDP.they are community owned. Charging rates are lower than at diesel operated charging services.part of the income is saved within the community for later maintenance and repair, yet the amount is very low. The remaining money is used to pay the operator.
• LOCAB has been partner of the GEF Small Grants programme and has also installed privately owned and funded solar battery charging stations in very remote regions, e.g. Mondulkiri (Gold Mine villages in the mountains).
• GIZ also cooperated with LOCAB in a iPPP solar battery station with a private investor in Kampong Chnang province. 2.88 kWp of solar panels were installed to charge around 45 batteries (around 50 Ah). GIZ provided an improved charge controller, testing equipment, training for the operator and customers as well as marketing support and support in accessing a loan. Yet, the cost of taking out money has been so high that the operator could not repay his loan with his income from solar battery charging.

Experiences from Cambodian Solar Battery Charging Stations (SBCS)

• The initiative capital investment is an obstacle that needs to be overcome
• Owners of existing battery charging stations are reluctant to invest, due to huge capital investment compared to diesel battery charging station, yet solar could be competitive due to very high diesel prices in Cambodia (|> 1.25 USD7l)
• Sun shine time (weather) is not constant, changes from day to day, especially in rainy season but even in dry season. Hence, some diesel is needed nearly every day.
• Information on the possibilities and functioning of solar energy is not widely spread, awareness needs to be created
• The business model and technology is new which needs to be explained to customers in order to overcome obstacles
• Customers are used to batteries being hot when they collect them from diesel run battery charging stations as these tend to overcharge the batteries. When batteries are charged properly at a solar station, they are not as hot which is why customers are of the opinion that they have not been charged. In Many cases customers complained that batteries became empty more quickly when charged with solar. The charging quality, according to them, was not satisfactory.
• A lot of awareness raising and training is needed.
• Very old car batteries are used. It is very difficult to change (de-)charging habits and educate customers about the advantages and importance of solar charging and the proper usage of batteries.
• There are allegedly more than 10,000 charging stations in Cambodia. Due to the poor charging technologies and low level of know-how of operators, focus should be put on capacity building with regards to technical aspects of charging, including safety and efficiency issues. With little effort, a lot of energy can be saved. At the moment, due to the high price of diesel, many diesel charging stations are not profitable as operators do not calculate all of their costs when pricing their services. Diesel charging is often a side business of rural business men.
• Even in areas where the grid is reaching, battery charging stations are common as they supply the poorest households who cannot afford grid connection. Also, batteries are used in times of pore cuts, for water pumping on the fields, etc.
• As the price for a kwH from a battery charged with diesel is the most expensive form of energy and as it is at the same time often the only source of electricity for rural households, which are among the poorest in Cambodia, new ways of providing these households with electricity need to be found.
• The efficiency of using solar energy to old car batteries is very low, especially keeping in mind the current level of know how with operators. If donors support rural electrification, battery charging is only a short time bridging technology which serves the lowest needs. Investing in solar home systems or rural mini grids (running on biomass, solar, or hybrid systems) will be a more sustainable investment with greater quality energy services.

Key Success Factors for Solar Battery Charging Stations (SBCS)

In general SBCS are comparably expensive, but can be an economic solution:

• Remote areas, which are not connected to the grid
• Where there is cell phone network
• Where diesel fuel costs and battery transport costs are high
• Income and energy demand are low

Important aspects to be considered for the success of SBCS are:

• Extensive marketing
• Additional services to be offered such as renting/selling batteries or recharge services for mobile phones or shaving heads
• Training of all local operators and technicians

Further Information

• You can also download the Rural electrification by battery charging stations as PDF
• Hydro Battery Charging Systems
• Battery Charging Systems
  
• Solar Portal on energypedia