Innovations are not enough where water scarcity is concerned, Ramesh Rengarajan, the former chief technology officer of General Electric Water and Process Technologies, said.’

An effective solution will involve a business model, creative packaging and a reasonable price, Rengarajan told about 50 people at a Massachusetts Institute of Technology lecture Wednesday.

People take many technologies and practices that waste huge amounts of water for granted, he said. It takes 10 gallons of water to produce a gallon of gasoline, he said, and 30 gallons of water to produce a single slice of bread.

‘We need to change conventional thinking and start thinking differently,’ he said.

Rengarajan, who recently left GE to start his own consulting company, also cited agriculture and aquaculture as major threats to environmental sustainability. Over 70 percent of the global water supply is used for agricultural purposes, and aquaculture is a major source of water pollution, he said.’

The U.S. imports 60 percent of farmed fish from countries where pollution laws are either non-existent or not enforced, he said.

‘Do you remember how civilization was formed?’ he said. ‘People moved to where the water was. Today, it’s the other way around.’

Rengarajan proposed the treatment and reuse of water as a solution. While this ‘toilet-to-tap’ method makes some people uneasy, he said, it has already been widely used with no harmful effects.’

To minimize environmental costs, he said water purification could be accomplished through a decentralized power system. He said he envisioned a device people could plug in and use on-site, like an air conditioner, to disinfect water.

The solution would have to be cost-effective in order to work, he said. While people are willing to pay for gas, oil and Starbucks coffee, he said, ‘nobody likes to pay for water.’

But he said he is optimistic about finding a solution that would not only benefit the environment but also become a multi-billion-dollar business.

‘I see it not as a challenge, but as an opportunity,’ he said.

Rengarajan’s talk was part of the MIT Energy Club’s lecture series, which brings prominent leaders of the energy world to campus on a biweekly basis, co-chair Mahesh Konduru said.

‘Two of the hottest topics in energy right now are in efficiency and water,’ he said. ‘We try to bring in speakers who are valuable in these areas.’

Attendee Dennis Kenney, a retired engineer, said he came to the lecture in order to gain insight on what he believes will be a coveted international resource in the near future.’

‘Last century we fought over oil,’ he said. ‘Water will be the next one.’