by: Hartatik
Purworejo – Farmers in Kaliwungu Lor Village, Ngombol Subdistrict, Purworejo Regency are all smiling. They had just harvested rice for the third planting season. In fact, for decades, they could only enjoy the harvest at most twice a season, because the irrigation of their rice fields depended on rainwater.
“From when I was a child until now, we have never thought of finding a solution so that farmers can get enough water for rice and secondary crops. This is the first time in Kaliwungu Lor’s history that we can reach the third planting season,” said Kaliwungu Lor Village Head, Ganjar Santoso (48), in late July 2023.
Furthermore, Santoso said he could realise the dream of farmers on the east side of the Kranjan River thanks to a solar water pump. The pump, which uses electricity from sunlight through solar panels, was donated by the Central Java Province Energy and Mineral Resources Agency (ESDM) which was handed over at the end of 2020. The value of the pump with a capacity of 11 kiloWatt per peak (kWp) is IDR 510,416,734 (USD 33,640).
The donation was given after Santoso complained about the farmers’ difficulty in getting irrigation during the dry season. This is despite the fact that the village has a dam that separates sea water from the Krajan River. Although Kaliwungu Lor is five kilometres from the sea, when tidal floods come, sea water can reach the river. Therefore, the village built a dam with four gates, 20 metres long, 25 metres wide and 3.5 metres deep.
Rain-fed
Irrigation has always the challenge every dry season, because the residents’ agricultural areas are rain-fed rice fields. During this time, fresh water from the dam is drawn using a diesel pump dating back to the Dutch colonial era. Furthermore, water from the dam is channelled using pipes to the irrigation network of farmers’ rice fields. The 6-cylinder diesel pump engine is serviced twice a year.
“Diesel pump maintenance is expensive. One service can cost up to Rp 8 million. You can imagine that in a year we have to spend up to Rp 16 million on servicing,” added Santoso.
In addition, the operation of this diesel-fuelled pump in one planting season can reach Rp 24 million, to irrigate 20-30 hectares (ha) of agricultural areas on the east side of the dam. Thus, the operational cost of the pump per ha of land can reach between Rp 800,000 and Rp 1,200,000 (USD 53 and USD 79). And these expenses are all borne by the farmers themselves. Not to mention that access to diesel is also increasingly difficult.
“We initially applied for the solar water pump worth Rp 1.7 billion (USD 112,000) to irrigate the rice fields on the east and west sides of the dam,” he explained.
However, the assistance that was disbursed was around Rp 500 million (USD 33,000), so the solar water pump without batteries is only intended for farmers’ land on the east side of the river, which is one metre higher than the dam. The solar pump operates from 8am to 4pm. According to him, the existence of water pumps connected to solar panels is very beneficial, not only environmentally friendly, but also helps farmers who are now no longer bothered with fuel operational expenses when using diesel pumps.
This is because the use of solar pumps is free, relying entirely on sunlight. In addition, maintenance of the solar panel is very easy, just clean it from dust and its service life can last 10-15 years.
Seeing this success, Santoso is now only bothered by the jealousy of farmers on the west side of the dam. They also asked for solar pumps to be installed. Meanwhile, the area of their rice fields is up to 60 hectares, or three times that of the farms on the east side of the dam.
“Hopefully we can again access assistance from the provincial government,” he said.
Moreover, Santoso said, the electricity from the installed solar panels, which is 7,000 Watts, has only been used for 1,700 Watts. And if the village later gets another offer of assistance, then he will ask for one more solar pump to irrigate the land on the west side of the dam.
Inspiring other villages
Kaliwungu Village’s success in dealing with irrigation by utilising solar energy has also inspired Krandegan Village in Bayan Subdistrict, Purworejo Regency. Krandegan village head, Dwinanto (43) Free irrigation was one of the village’s resilience systems built after he was appointed as village head in 2013. Now the system has reaped its rewards. Dwinanto said that in the years before he became the village head, farmers in Krandegan Village could only grow one crop a year. They should have been able to plant three times.
As a result, many farmers have left their rice fields unattended. This is because the village is located downstream from the technical irrigation of the Jrakah Dam on the Dulang River, so the water runs out on the way to the village.
Farmers who survive inevitably rely on rain. Instead, diesel pumps have become the choice of farmers who plant rice during the dry season, or the second and third planting seasons.
Nurfuadi (55), one of the farmers, admitted that if he wants his rice fields not to dry up during the dry season, he has to spend more. For a rice field of around 7,000 m2, he spends more than Rp 3 million (USD 198) to rent a pump and its fuel.
Due to the condition of the farmers, Dwinanto mobilised donations from the people of Krandegan who were successful in running their businesses. He then launched a free irrigation programme. From the donated money, ten pumping machines were purchased to draw water from the Dulang River, Jali River, and boreholes. The water is channelled through existing tertiary irrigation channels to the farmers’ fields.
“These ten pumping machines can irrigate approximately 70 hectares of rice fields,” he said.
The community was not charged for the operational costs. Through this free irrigation programme, Krandegan farmers have enjoyed two harvests during the dry season. Although the farmers no longer have water shortages, there is still something on Dwinanto’s mind.
“I thought it was impossible for the village government to continue to rely on donations to keep the free irrigation running. It is better that the donations that are now regularly collected can be allocated for other social purposes,” he said.
In light of these problems, it can be said that the free irrigation programme using diesel pumps is difficult to continue. The cost of fuel is the biggest burden. Even donors have indicated that they will stop their donations in the near future. For farmers, this is a serious threat.
The experience of neighbouring villages proves that without subsidised fuel costs, their water pumping machines go unused for years. The same thing is likely to happen in Krandegan Village. If the fuel subsidy is discontinued by donors, farmers will return to rain-fed rice farming practices with the number of harvests dropping from three times a year to once a year.
This is because the cost of fuel, which is the largest cost component, is provided by donors. Village funds cannot be used to purchase fuel. In a year, the fuel purchase fund covered by donors can be up to IDR 200 million (USD 13,180) or IDR 500 thousand (USD 33) per day.
Not to mention farmers have to provide the cost of lubricating the pump every two months at around IDR 300 thousand (USD 20), or IDR 2 million (USD 132) per machine for one year. For all 8 machines, farmers must independently provide lubricant costs of around IDR 15 million (USD 988). Then other operational costs such as machine and pump maintenance costs, farmers spend around IDR 2.5 million (USD 165) per year.
Summing up the three components of operational and maintenance costs, it costs an average of IDR 200 million (USD 13,180) per year or around IDR 2.67 million (USD 176) per hectare per year. Meanwhile, the development of solar-powered pumps, although high in initial investment, can be passed on to children and grandchildren.
Dwinanto also submitted a proposal for solar power plant procurement to the Central Java Provincial Government. This year, the solar power plant along with the solar panels and the pump can be realised. The Central Java Provincial Government disbursed a budget of Rp 450 million (USD 30,000) from the state budget to realise the construction.
The solar power plant in the village is designated as an Independent Village. The solar-powered irrigation system has a capacity of about 18,800 Watts or the equivalent of 2 diesel engines capable of operating five water pumps. The water pump, which is integrated with the solar power plant, is capable of producing a water discharge of 77 litres/second, 279 cubic metres per hour.
“I believe the value of benefits felt by farmers from the development of solar energy can be greater and longer term,” said Dwinanto.
According to the Indonesia Solar Energy Outlook 2023 report issued by the Institute for Essential Services Reform (IESR), solar power plays an important role in deep decarbonisation in Indonesia by 2060 or sooner by 2050, at least 88% of installed power capacity will come from solar power by 2050.
Unfortunately, solar power utilisation in Indonesia has only reached 0.2 Giga Watt peek (GWp) of installed capacity and will only generate less than 1% of total electricity generation by the end of 2021.
Alvin Putra Sisdwinugraha, Researcher of Electricity System and Renewable Energy at IESR’s Solar Energy Talk #3 said that solar energy in PLN’s 2021-2030 Electricity Supply Business Plan (RUPTL) will play an important role in Indonesia’s electricity to achieve net zero emission (NZE), while utility scale is still the biggest contributor.
“The agricultural sector is one of the potential clusters in the RUPTL in addition to the mining sector, tourism sector, rooftop solar power plants (PLTS), floating solar power plants, and other sectors with a total capacity of 2.1 Giga Watts,” he said.
Banner photo: A solar power generation system that powers an irrigation pump in Krandegan Village, Bayan Subdistrict, Purworejo District, Central Java. (Hartatik)
