Indonesia: ice from solar energy

The fishing village of Sulamu in the south-east of Indonesia has everything ready for the arrival of the solar ice maker. A regional entrepreneur has constructed a building there to make ice blocks. The prototype of the machine, which has already successfully completed countless test runs, is packed up and ready to go in Surabaya, the capital of East Java province. All that is needed now is for the pandemic-related restrictions to be lifted and then the machine can get on the road – accompanied by experts to install it and train local staff.

Sulamu is in the province of East Nusa Tenggara, a good three hours by plane from the Indonesian capital. It is one of the least developed provinces in Indonesia. People make a living from farming and fishing. A lack of storage facilities means that there are huge food losses. Sulamu is a typical example of a small village on the archipelago that comprises some 17,500 islands with over 100,000 kilometres of coastline. Indonesia, which has a population of roughly 275 million, wants to conserve its fish stocks and safeguard or increase the income of local fishers. Uninterrupted chilling of the catch is crucial to achieving this. GIZ initiated and supported the development of a solar-powered ice maker to address this problem. Production was established in Indonesia in conjunction with several domestic, German and European companies.

Innovative technology for the local fishing sector

Development started in 2017, as an integral part of the Indonesian-German energy programme that had a number of different projects and commissioning parties. Currently the initiative is anchored in the ExploRE project (Strategic Exploration of Economic Mitigation Potential through Renewables), which was commissioned by the German Environment Ministry (BMU

The challenge presented by the solar-powered ice block machine was the need to combine two technologies – solar power and innovative cooling technology. The solar ice maker was developed by the Institute of Air Handling and Refrigeration (ILK) in Dresden. The technology is in keeping with the philosophy of Industry 4.0 and guarantees dynamic production of up to 1.2 tonnes of ice blocks per day, automatically adjusting to the amount of solar energy available. Neither mains electricity nor large, expensive battery capacity are required. The technology is unique in that it is sensor-controlled, operates entirely on its own energy supply, and is climate neutral. Danny Wijaya, the engineer responsible in the team at the Indonesian manufacturer AIREF, is proud of this. AIREF is one of nine private businesses that cofinanced and drove forward efforts to put this Dresden-based development into practice in Indonesia.

It is now possible to produce blocks of ice in places that are off-grid and have no diesel generators. The energy provided by photovoltaics thanks to the high level of solar irradiation is used to make ice, which is then constantly available to chill the locally caught fish. It does this with the help of a natural coolant in the form of propane and ordinary salt water, which acts as a thermal energy store. Fish packed in ice has a higher value – in the case of sustainably caught tuna, for example, over 50 per cent more. That boosts the income of those fishers who operate sustainably, especially those in disadvantaged regions of Indonesia. Just one single solar ice maker saves 40 tonnes of CO₂