Deng dealer Arthur Manu stands outside his shop in Nkhoranza, Ghana.

In Ghana, 40% of the population aren’t connected to the mains power supply, and it is not reliable even for those who are.

Deng’s solution is solar power. The company sells a range of photovoltaic (PV) systems, starting with a standalone version for the home costing US$500 and larger versions for schools and hospitals costing up to US$1500.

If we want to do our work in the night, we tell our father to put the solar on first to do the work. If you do not have solar, you can’t learn.

Senasi, child at orphanage

Background

Although 49% of households in Ghana have access to mains electricity, the generation capacity is inadequate, resulting in many unplanned power cuts. Most of those without electricity live in the rural areas. Here the main income is from seasonal agriculture, and many people are cautious about connecting to the mains were it to arrive, for fear that they will run up a bill that they cannot afford to pay.

Ghana is ideally placed to make use of solar photovoltaics (PV), especially in rural areas, but there is a need to rapidly increase the number of people trained in installation and maintenance. Deng, an established engineering business in Accra, supplies solar PV systems both directly and through a dealer network, bringing more reliable power to those already connected to the grid and those in rural areas currently off grid. It uses high quality components to minimise the risk of faults, and ensures that all technicians and dealers are fully trained in installation and maintenance.

PV modules for a grid backup system on the roof of an NGO in Accra.

The organisation

Deng Ltd is a general engineering business in Accra, the capital of Ghana. It was founded in 1988 and started working with solar PV in 1998 - a natural progression from its core business of generators and water pumps. In 2009, it employed 25 people, with another 50 people working indirectly (as dealers etc). The business runs on a commercial basis, although some grant-funding was useful in the early stages to enable Deng to collaborate with European PV businesses, to establish supply chains for PV modules and other components, and to set up the PV training centre. In 2009, its turnover was US$1.5 million.

The technology

How does it work?

Photovoltaic (PV) modules generate electricity from sunlight. Used with rechargeable batteries to store electricity, they can provide an independent dc electricity supply system that can be used both day and night. A PV system incorporates a charge controller, which prevents the battery from being over-charged or deep-discharged, and may also include an inverter to convert dc power to ac, thus allowing the use of ac appliances.

PV module powering lights for a roadside stall.

Deng sells and installs several different types of PV system, but the bulk of its PV business is the supply of standalone systems. Deng also provides PV systems to supply emergency backup power during frequent mains failures. These systems are sold mainly in and around Accra, to businesses, public bodies, NGOs and private homes. The largest installed to date is a 9.2 kWp grid backup at the central courts in Accra, where the use of PV maintains lighting and thus enables court business to keep going during power cuts.

The smallest systems sold are solar lanterns, which are assembled locally using components from the Netherlands, and have an expected lifetime of three years, after which the battery and sometimes the light bulb need replacing.

How much does it cost and how do users pay?

US$1 = 8,500 Cedi [April 2007]

The solar home systems range in price from US$ 530 (4.5 million Cedi) for a 14 Wp system to US$1,470 (12.5 million Cedi) for a 100 Wp system. Most customers pay cash on installation.

Deng provides three months credit on components to its network of rural dealers. Some of them may permit reliable customers to pay two thirds up front and the remaining third within three months – the credit term they have from Deng. Commercial solar PV systems are paid for at installation.

Solar powered freezer.

How is it manufactured, promoted and maintained?

Deng recognised that a major reason for the low success of PV in Ghana was lack of trained people for system design, installation and maintenance. It therefore set up a training centre in Accra, with the Kwame Nkrumah University of Science and Technology (KNUST) as a partner. The training centre has worked with Global Sustainable Energy Solutions, an Australian consultancy specialising in solar PV training, to develop the training materials and run the initial courses. Eight courses were run between 2006 and 2007, training about 120 people – men and women – in the use of solar PV. A full course takes 12 days, and covers design, assembly, installation and fault analysis, concluding with performing an actual installation. All the training courses are accredited by the Institute of Sustainable Power to ensure consistent quality.

All the Deng technicians and dealers go through the solar PV training course, and all new dealers must also complete a business training course. Deng installations include a year’s warranty, and commercial systems usually include a service contract. The Deng dealers do not necessarily offer a warranty, and this is one of the reasons for using good-quality PV modules and charge controllers. However, as a dealer’s reputation is important for maintaining their business, they will usually carry out repairs for customers if their travel expenses are paid. Both Deng and the dealers keep records of systems sold.

Benefits

Between 1998 and 2007, Deng and its dealers sold about 6,000 solar lanterns, and sold and installed over 1,000 other PV systems. In addition, two of the Deng dealers run PV-powered battery charging stations, where local people can bring lead-acid batteries to be recharged as needed. This is a popular service, because it provides people with the benefits of PV electricity without the cost of buying the PV module.

I have a cousin and his children used to run up enormous electricity bills when he was away from home so I suggested that he bought a PV system instead. Now they can only use the lights for a few hours each evening, and they cannot run up bills.

Mr Kwasi Affa, retired driver, Nkhoranza

Environmental benefits

Households use solar-home-systems for lighting and mobile phone charging, and larger systems are sometimes used for television as well. Using PV instead of kerosene for lighting gives better light and a cleaner environment, and typically saves US$2.40/month (20,000 Cedi) by replacing two kerosene lamps.

Social benefits

Education has benefited from the use of solar PV lighting in Ghana. Children have good quality dependable light at home so they can study in the evening. Both adults and children are making use of 600 schools that have been equipped with 80 Wp PV systems so that they can remain open in the evening for classes and homework sessions.

Healthcare also benefits, through the provision of lanterns to traditional birth attendants, and also through PV systems in hospitals and clinics. These are used for lighting, but also for refrigeration of vaccines and insulin, and for providing a reliable water supply. Improving the lighting and facilities in rural clinics is making healthcare more accessible for people, as they no longer have to travel into town for treatment. PV systems in health centres are no use if they break down, and Deng has supported the installation programme by running courses for health service technicians at the training centre.

The people who benefit most from PV services are in the more remote parts of Ghana.

Economic and employment benefits

The PV work of Deng has directly provided employment to about 11 people, including technicians at Deng head office and the Deng dealers. The dealers supply PV systems and two of them run battery charging stations as well. A 200 W system costing about US$2400 (20 million Cedi) can charge four batteries per day and bring in a daily income of about US$2.40 (20,000 Cedi - equivalent to the national minimum wage), thus repaying the capital cost of the system in about three years. This forms a good basis on which to grow a PV installation business. The use of PV for lighting has extended working hours for shops and other small businesses.

In the commercial arena, businesses and public organisations using solar PV for gridbackup now have the ability to continue working during power cuts and voltage variations. Although more expensive, PV is preferred to diesel generators for back-up power because it is silent.

Potential for growth and replication

The lack of adequate grid capacity in Ghana will probably result in sustained demand for solar PV equipment. The people who would benefit most from PV services are in the more remote parts of the country, and Deng is growing its network of dealers in these areas. The training centre provides the ideal opportunity for prospective dealers to be trained in the installation and maintenance of solar PV, to ensure good quality systems and service.

Update: what happened next?

By 2009, Deng had installed a total of 1,200 PV systems and supplied 7,000 solar lanterns. It had also developed a new phone charging system, with 35 sold.

The Deng Solar Training Centre has become a separate company (DSTC Ltd), providing solar PV training and general business training to dealers, as well as basic community awareness training. A chain of 20 trained Solar Dealers is also being developed in rural districts under the auspices of a World Bank funded solar project.