By Nita Bhalla

KITUI, Kenya, June 6 (Thomson Reuters Foundation) - Kenyan farmer Abel Mutie Mathoka believed it needs to be a joke when he was informed he might water his drought-hit crops more inexpensively, cleanly and efficiently using a pump sustained by cotton waste.

"Who could think it's possible to make a fuel much better than diesel from cotton seeds? I didn't!" chuckled Mathoka, crouching down to examine the watermelons on his 10-acre (four-hectare) shared plot in Ituri village in Kenya's southeast Kitui county.

"But it works," he stated, walking over to a nearby tree and plucking a big green pawpaw. "Irrigation with this biodiesel water pump has helped me get higher yields, particularly throughout drought durations."

Mathoka stated his earnings had doubled in the two years he has been pumping water using biodiesel, which is both more effective and 20 shillings ($0.20) per litre less than routine diesel.

The biodiesel he is using is not just great news for him - it is also excellent news for the world.

Unlike the majority of biofuels, which are originated from crops such as maize, sugarcane, soybean, rapeseed and jatropha curcas, it is made from a by-product of the cotton-making procedure.

That indicates that as well as being cleaner and less expensive than regular fuel, it is more sustainable than other biofuels because no additional land is required to produce it.

From Brazil to Indonesia, the rush to cultivate biofuel crops has actually driven forest communities off their land and pressed farmers to change from crops-for-food to more profitable crops-for-fuel - intensifying food shortages.

"Our biodiesel originates from squashing cotton seeds left over as waste after ginning - the process of separating the seeds from raw cotton," stated Taher Zavery, handling director of Zaynagro Industries Ltd, the Kitui-based business producing the biodiesel.

"We began producing and utilizing it to power our cotton ginning factory in 2011. With increased production, we now use it for our trucks, sell it to the United Nations to run some of their buses - and likewise to regional farmers for irrigation."

More than 1,200 farmers in Kitui have so far bought biodiesel pumps for irrigation as part of an effort introduced by Zaynagro in 2015, stated Zavery.

DRY RIVER BEDS

Climate modification is taking a toll throughout east Africa and increasingly erratic weather condition is ending up being commonplace in nations such as Kenya, Somalia, Uganda and Ethiopia, leading to lower rains.

The repeating droughts are damaging crops and pastures and are starving animals - pressing millions of people in the Horn of Africa to the edge of severe appetite.

The variety of Kenyans in need of food help in March rose by nearly 70 percent over a period of 8 months to 1.1 million, largely due to bad rains, according to government figures.

With nearly half Kenya's 47 counties stated to have a serious shortage of rain, humanitarian companies are warning of increased hunger in the months ahead.

"Only light rainfall is anticipated through June ... and this is not anticipated to minimize dry spell in affected areas of Kenya and Somalia," said the Famine Early Warning Systems Network in its latest report.

"Well below-average crop production, bad livestock body conditions, and increased regional food rates are anticipated, which will reduce bad households' access to food."

In Kitui's Kyuso area, the indications are already evident.

Rivers, water pans and dams are drying up as an outcome of the prolonged drought.

Villagers complain of trekking longer ranges - sometimes more than 10 km (6 miles) with their donkeys laden with empty jerry cans searching for water.

Small-scale farmers, the majority of whom depend on rain-fed farming, discuss strategies to offer their goats to make ends fulfill if the harvest is bad.

BATTLING DROUGHT WITH BIODIESEL

But not all Kitui's farmers are worried.

A little but growing number are shedding their concern of reliance on the weather - and investing in watering systems powered by Zaynagro's cotton seed biodiesel through a pay-as-you-go plan introduced more than 3 years earlier.

Neighbouring farmers band together to purchase the watering system - which includes the biodiesel pump, 12 metres of pipes and 10 litres of biodiesel - at expenses starting from 32,000 shillings, depending on the size of the pump.

The farmers make a preliminary payment, then pay interest-free regular monthly instalments till the total is settled. They purchase the biodiesel to run the pumps from Zaynagro at 80 shillings a litre.

Farmer Alex Babu Kitheka, 39, stated the biodiesel pump enabled him to water a bigger portion of his one-acre plot, where he grows a range of vegetables including maize, tomatoes, spinach and sweet potatoes.

"With a diesel pump, maize yields were lower and I would get 15,000 shillings in 3 months. With the biodiesel pump, I can make 45,000 shillings," said Alex Babu Kitheka, standing near his plot in Ilangilo village, 40 km (25 miles) from Kitui town.

CIRCULAR ECONOMY

Other farmers point to the scheme as a major advantage in assisting enhance their output.

"The instalment scheme is excellent. Most farmers do not have the cash and can not quickly get a loan to purchase a pump like this," stated Maurice Kitheka Munyoki, 41, as he stood beside his blue biodiesel pump.

"Having a plan like this helps us a lot. Our yields are good which suggests we can pay off the expense of the pump gradually in small amounts, and have money left over to pay the school charges."

Zaynagro's initiative is still in its early phases, with few farmers having actually repaid the full cost of the pumps.

But such biofuel plans are appealing because they create a circular economy by turning waste to biofuel for profit, said Sanjoy Sanyal, senior partner for Clean Energy Finance at the World Resources Institute.

The simplicity of the design - easy-to-use, robust technology, assured supply of biodiesel combined with a pay-as-you-go scheme - might help energize rural Africa, he said.

"There is a mosaic of sustainable energy options on the planet. The key concern is testing ideas and methods in a collaborative style," said Sanyal.

"Other cotton ginning factories in the area need to try and gain from this experiment. Banks must start exploring with loans to groups of farmers. International donors and investors need to support experimentation."

($1 = 101.3000 Kenyan shillings) (Reporting by Nita Bhalla @nitabhalla, Editing by Claire Cozens. Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, ladies's and LGBT+ rights, human trafficking, home rights and environment modification. Visit http://news.trust.org)