Environment: Sugar cane is central to sustainable energy plans
Conservation in Mauritius got off to a bad start when the first influx of humans rapidly wiped out the unsuspecting dodo. The island’s habitat has done better since, thanks to an economy built on sugar cane. This tall grass, covering a third of the land area, has kept much of the volcanic island’s green skin intact and, with the right technology, could help to make the next generation more self-sufficient with green energy.
A sustainable island project, known as Maurice Ile Durable (MID), is taking shape, but requires decisive action, says Khalil Elahee, an associate professor of engineering at the University of Mauritius who is on the project’s strategy committee at the prime minister’s office.
The project has already funded small solar-heated water and fluorescent lamp schemes, but Mr Elahee sees the role of sugar cane as essential to the success of this holistic plan, that ranges from power generation to harvesting algae from the sea, reforestation and wind power.
“We can re-engineer the cane industry to produce energy from biomass, produce bioplastics, export biofuel and bio-fertilisers. In turn, we can go some way towards food security by intercropping in the cane fields. It will reduce imports and it’s in harmony with tourism, the idea of a green island,” says Mr Elahee.
The island’s transport and most of its power stations rely on fuel imported from India or South Africa but the cane industry already supplies 20 per cent of the nation’s electricity from the sugar mills’ waste that is burnt to produce steam-generated power.
“With gasification of the biomass, cane could provide all of the island’s energy. It would take 10 years of research to reach a commercial application, similar to what they’re doing in the US. But we have to stop talking and start doing it, with the right industrial partner,” says Mr Elahee.
Local energy consultants agree that cane energy is beneficial. It is low-cost, frees the country from import dependency and can avert the real threat of blackouts from the existing fossil-fuelled infrastructure.
Mott McDonald, the British consultancy, is working on a feasibility study but Mr Elahee warns that the decline of sugar cultivation threatens the plan. “The area of land cultivated for sugar cane has been reducing at an alarming rate for the past decade. If cane production falls below a certain level, it will no longer be economic for it to produce energy.”
The big sugar estates that mill the cane from the smallholders also warn that the economy is at risk from declining sugar production, as planters are ageing and young people flow to the towns and better-paid jobs.
“We need well-planned agriculture. When the people move out of sugar cane, they cease organised agriculture. Where there’s sugar cane, there’s irrigation, there’s a system,” says Jacques d’Unienville, who runs Omnicane, a leading sugar, power and ethanol producer. “To persuade the small planters to keep producing, we have a new movement. The industry provides management services, helps planters to form co-operatives and join the Fairtrade scheme.
“Sugar cane is one of the most efficient carbon converters. It takes sunlight and converts it into green by-products. Mauritius is the pioneer. In 1957, it was the first country to produce electricity from bagasse [sugar biomass],” says Mr d’Unienville.
Mauritius was also the first country to replace petrol and diesel with ethanol, during the second world war when there was an oil embargo. The war was an interesting lesson. No oil meant no food could be imported. “In the sugar cane fields, we were growing our own food.”
Mauritius belongs to the International Sugar Cane Bio-mass Utilisation Consortium, but the local industry sees Mr Elahee’s plans for green energy as ambitious. “It works in a test tube but it would take 20 years of research to develop gasification to that level,” says Mr d’Unienville.
Far from the white beaches and green ocean views that draw in the tourists, Solid Waste Recycling is bringing more green technology to the island. From his bare office near St Martin, Patrick Maurel, the company’s chief executive, watches trucks unload on a stinking pile of municipal rubbish. “Mauritius produces 400,000 tonnes of rubbish a year. We hope to be allocated half of that, which we will turn into 40,000 tonnes of enriched compost. We see this as a component of the sustainable island project,” he says.
“This compost improves farmers’ yield, helps water retention and rebalances the PH ratio of the soil. After years of chemical fertiliser being used on the sugar fields, our soil has become so acidic that it needs alkaline additives. These are also running out. They are even putting cement in the soil on some farms. It’s a clean system and our aim is to move towards a zero-waste system. That would be a first,” says Mr Maurel.
Source: Financial Times