Can going green solve some of India's problems?
At his factory in the outskirts of Mumbai, Nitin Bondal is staring proudly at a large machine. The 4m (13ft) orange structure has a futuristic air, as it stands, pride of place, in the corner of a dusty, decades-old workshop, filled with the stench of factory fumes.
Two men climb up to the top, and start pouring bags of broken plastic down a chute.
When Mr Bondal presses a button, the machine whirrs to life, and in about an hour, a form of petrol starts to drip into a bottle at the other end.
"This is our prototype machine, it turns all types of waste into crude oil," he says proudly.
"We put all kinds of things in here, everything from plastic to electronic waste to old tyres."
Mr Bondal says this technology has the capability to convert 150 tonnes of waste into 150,000 litres of crude oil, every day, once fully operational.
"It works on what we call the polycrack system," says Mr Bondal. "We are cooking the material and converting it into gas. When you heat any matter there is hydrogen and carbon available," he adds.
As Mr Bondal explains, this gas is then passed through a "special catalyst", which breaks the molecules down to form hydrocarbon gas and petroleum gas, which when cooled becomes liquid petroleum fuel.Waste management
Mr Bondal and his business partner, Raghuvendra Rao - who both have a background in the oil industry and spent five years developing their company, Sustainable Technologies & Environmental Projects (Steps) - hope to start selling the oil later this year.
The company has already attracted $12m (£7.7m) of investment.
Green technology is proving lucrative in India, clean energy investments here were worth $10.3bn, a growth of 52% on 2011, according to Bloomberg New Energy Finance.
This means that India had the highest rate of growth in green technologies of any other major world economy, with wind and solar areas being where most money is being pumped into.
India uses energy inefficiently, and many green tech entrepreneurs see innovation as a way of bridging this gap, and making money.Innovative stoves
Take Neha Juneja - a 27-year-old entrepreneur from Mumbai who, together with a friend, spotted a green business opportunity in rural India.
End Quote Jonathan Winer Nereus Capital
India is a unique market for alternative energy, given the country's large power deficit, high electricity costs, and challenges in traditional thermal power”
In a village in Maharahstra, she demonstrates the device she hopes will make her money - the Greenway Grameen Infra, an eco-friendly cook stove.
Hundreds of millions of Indians still prepare food on centuries old mud stoves, but the smoke from these emit harmful greenhouse gases.
Research from The Indian National Initiative for Advanced Biomass Cookstoves estimated that more than 4% of the country's greenhouse gas emissions come from such cookers.
Ms Juneja's Greenway stove is said to save 1,600kgs of wood, and mitigates over two tonnes of greenhouse gas emissions per stove per year.
"The stove is a very simple device," says Ms Juneja.
"We didn't design it in a lab, we started with an abstract prototype and travelled across India for nine months to understand what people in villagers want, without changing their culinary habits."
The cooker is designed with a component that automatically sucks in oxygen from the outside, and supplies it to the fuel to ensure that the combustion is proper and clean, explains Ms Juneja.
This effectively means all the fuels burns completely, she says.
The product was devised after Ms Juneja and her business partner Ankit Mathur, who both quit well-paid jobs to start the business, spent months travelling to villages to see how people cook and ensure that anything they created didn't change culinary habits.
"It is better because it uses less wood," says Saku Bhala, who lives in the village and has started to use one of the new stoves.
"It doesn't create burning in my eyes or on my body."
More than 6,000 of the stoves have been sold since they went on sale at the start of this year.
They are particularly popular in the southern state of Karnataka, where they are even being given as wedding gifts.Green potential
"I would say there's a lot of money to be made in green energy in India because the solutions [people] are coming up [with] solve basic infrastructure problems, which would be hard to solve otherwise," says Ms Juneja.
The scope for clean energy in India is huge, agrees Jonathan Winer, the managing partner of Nereus Capital, a firm that finances alternative energy power plants in India.
"India is a unique market for alternative energy, given the country's large power deficit, high electricity costs, and challenges in traditional thermal power," he says.
"The innovation driving market adoption is not necessarily new technologies, but rather applying proven technologies in smaller, more decentralised applications that can provide excess return."
It is a view shared by long-time green technology investor, Sanjeev Krishnan, who says that while the technologies are not groundbreaking, the ways they are being deployed in India is what is changing the market.
Mr Krishnan cites examples such as solar power schemes, which are providing off-grid electricity to power telecoms towers, as ways where established clean technologies are being used differently.
"Waste is being turned into a commodity, instead of purely landfilled or renewable based micro-grids, [and] this has the potential to address many of India's energy issues at a time of economic slowdown," he says.