CLEVELAND, Ohio -- Two Case Western University engineering students and a Cleveland Institute of Art graduate have invented a household device you didn't know you needed.

But they're betting you do. Or you will.

It's a smart meter for the shower in your home, called Sprav (rhymes with brave, created by combining spray and save). Snap it on the pipe just behind the shower head, program it on your smart phone or tablet, and start saving money.

The shower is the place where every minute of hot water costs consumers, on average, about 19 cents. You and your parents before you suspected something like that. But who knew?

Sprav will tell you - and your water-soaked teen - when the fun is over and it's time to shut off the water.

The Sprav won't turn the water off, but the LED indicator will move from green to yellow and finally flash red when time is up. And it may also begin beeping, though that is still under design.

Sprav's on-board sensors will measure the amount of water used by listening to its flow in the plumbing, and it will measure the temperature of the pipe.

It will store that data, and at your command, a Bluetooth transceiver will send it to your smart phone, where an app you have downloaded will calculate how much water and how much energy each shower consumed.

A common "coin" cell battery used in medical devices and pedometers will power the miniaturized guts of the Sprav .

The device is the brainchild of Case engineering seniors Craig Lewis and C.J Valle - along with Andrew Schad, an industrial designer and May 2013 Cleveland Institute of Art graduate.

They are the co-founders of Sprav Water, LLC.

"There are huge saving potentials here," said Valle. "And people are not even aware of it. Also this device could have a huge environmental impact because it will reduce wastewater and energy."

Since August, the three entrepreneurs have been under the tutelage of Bizdom, the startup accelerator founded by Cleveland Cavaliers owner Dan Gilbert.

And now Kickstarter, the web-based fundraising platform that appeals directly to the public for seed money, has accepted them.

Sprav Water's pledge appeal, posted Oct. 17, explains the device and urges investors to give as little as $1 or as much as they can.

The first 100 who pledge at least $39 will be in line to receive the first mass-produced units next spring. After the first 100 units are gone, backers will be able to get the base model for $49.

Right now the company has built a few prototypes, thanks in part to their use of the CWRU think[Box], a kind of campus industrial workshop open to Case students.

Lewis said the company needs to raise $80,000 to begin manufacturing. Under the KickStarter rules, the company has given itself just 30 days to reach the goal. If it fails, the pledges will be voided and Sprav will have to look elsewhere.

By Monday, Kickstarter reported that 214 backers had pledged $12,652.

"It was great seeing so much support so early. We really appreciate all of the great comments and feedback we have received so far," said Lewis.

Bizdom typically gives the companies in which it invests six months of intense monitoring, said Paul Allen, the Cleveland leader of Bizdom.

"We saw in Craig Lewis and the team a smart group of founders with complementary skills," said Allen. "And we saw very strong characters. We look for great ideas, but also equally we look for character and other attributes to be entrepreneurs.

"We were impressed with their ability to think clearly and rationally about the business model. And their technical skills gave us confidence that they would be able to pull this together," he said.

Lewis and Valle said Sprav Water's origins were a challenge they tackled for extra credit in a freshman engineering class.

"It was to come up with some device that would help people to become more green in daily habits," said Valle. "It could be energy or water. We took the combination."

Before Bizdom's involvement, Blackstone LaunchPad, a campus entrepreneurship program of the Blackstone Charitable Foundation at CWRU and 9 other campuses, worked with the students to take the class project into the real world.

"These guys really got down to business," Bob Sopko, director of the program at CWRU, said of Craig, Valle and Schad. Sopko has worked with a number of student engineering teams trying to launch companies.

"They designed it, prototyped it, and got input. Then they adjusted the designs, miniaturized it, kept refining it, and finally asked what the market would accept," he said. "They have kept moving forward."

After Valle and Lewis teamed up with Schad at CIA, they began entering design competitions. Last year they took first place in the prestigious Saint-Gobain Design Competition.

Schad, who now works for Chrysler, said the initial inspiration for his design was the standard curvature of the visible plumbing just behind the showerhead.

The device, though packed with sensors and a flat circuit board, had to be in a shape that was more round than angular.

It had to be small. And it had to give the consumer a quick connect feature.

"I wanted it to be seamlessly integrated into your bathroom," said Schad, adding that the resulting elegant teardrop shape the team came up with is an icon for what it measures - water.

Fitting into the palm of your hand, Sprav looks sleek and ultra-modern and requires no tools to install.

Still, it is a tool. And a very pragmatic one, said Valle.

"We are fundamentally a green company trying to deliver a product that is good for the environment and that helps people save money."