Garage Invention Turns Restaurants Into Power Plants

By Alexis Madrigal January 7, 2009 | 3:38 pm | Categories: Energy, Environment, Food

Would you like power with those fries?

A new garage-engineered generator burns the waste oil from restaurants’ deep fryers to generate electricity and hot water. Put 80 gallons of grease into the Vegawatt each week, and its creators promise it will generate about 5 kilowatts of power.

That’s about 10 percent of the total energy needs of Finz, a seafood restaurant in Dedham, Massachusetts, where the first Vegawatt is being tested. At New England electricity rates, the system offsets about $2.50 worth of electricity with each gallon of waste oil poured into it.

Vegawatt’s founder and inventor, James Peret, estimates that restaurants purchasing the $22,000 machine will save about $1,000 per month in electricity costs, for a payback time of two years.

"You take this waste resource and make it a profit center," said Peret, who spent four long years cooking up the project in his garage. "When I started telling people, they said, ‘Someone’s gotta have done this.’ I’d run into more people. They’d say, ‘Why hasn’t anyone done this?’ My only response was, ‘I don’t know; it seems like a good idea.’"

While Vegawatt is a small solution, Peret’s invention is a very clever embodiment of several long-cherished alternative-energy ideas: capturing both the heat and power from fuel combustion, making energy where it’s used, and recycling used resources. Big industrial plants that make paper, for example, have long taken advantage of these concepts to save on their utility bills, but the Vegawatt will be the first product that could turn thousands of fast food restaurants into mini power plants.

"Now the restaurant owners are going to be motivated to put every single drop of waste oil into this thing, because it will pay for itself," Peret said.

And importantly, it provides convenience for restaurateurs or Burger
King managers, instead of subtracting it, like so many green solutions seem to.

Restaurants that fry delicious things like chicken and french fries generate dozens of gallons of waste oil that have to be stored in barrels out back. Because used cooking oil is considered a low-grade hazardous material, they haven’t been allowed to just throw it away; they generally had to pay rendering-plant operators to come. But it is now a sellers’ market for grease.

Higher crude prices have made other types of oil more expensive. Biodiesel makers and renderers have become increasingly willing to pay up to 40 cents a gallon for the stuff. There have even been reports of "biodiesel pirates" stealing fryer grease.

In fact, Vegawatt is derived from the home-brew fuel movement that many trace back to Dr. Thomas Reed, who popularized a recipe to convert waste cooking oil into biodiesel more than 20 years ago. Peret converted his truck to run on straight vegetable oil, or SVO to home brewers. But he was troubled by the inefficiency of the process.

"If you want to run waste vegetable oil in your car, it’s not as simple as going behind a restaurant and filling up," Peret said. "People that do this spend the majority of their free time collecting fuel from restaurants."

Peret realized he could use the same engine technology to power an on-site generator and defray a restaurant’s electricity costs.

"It’s not difficult to go from spinning tires to spinning magnets," he said


So he created a test unit — which you can see at the back of his garage in the top photo — that’s basically a diesel generator hacked to run waste cooking oil. It feeds power directly into the restaurant’s electrical system through a 30 amp hook-in.

Vegawatt is more efficient than a typical coal or natural gas plant. Peret said it can capture 70 percent of the fuel’s caloric value. That’s because the generator captures and uses the waste heat it generates.

"All the water [the restaurant] would send to its boiler, instead of sending it straight there from the city, we run it through our heat exchanger first," Peret said. "Depending on the flow, [the water] can go into the hot water heater at 120 degrees." (This non-electrical energy savings is included in the 5-kilowatt rating cited above.)

The big power plants, though technically very efficient, waste most of the fuel they burn. After accounting for all the sources of energy waste "what you are left with … is just 27.6 units of usable energy out of every 100 units you started with," energy researcher Benjamin Sovacool explained in his recent book, The Dirty Energy Dilemma. "In terms of making toast, it would have been nearly four times more efficient just to burn a lump of coal and place your bread over the flame."

Biomass energy sources — like waste wood, switchgrass or cooking oil — are best when used right near the source of their creation. Dragging the stuff creates more emissions and raises the cost of the fuel. Vegawatt doesn’t have that problem. By company estimates, the Vegawatt generates 50 percent less carbon dioxide than a comparable amount of electricity from a coal power plant.

"In terms of the amount of energy that it takes to transport this waste, it’s a french fry," Peret said. "You just feed the guy who is picking up the bucket and pouring it into the system."

Forest Gregg, an alternative-fuels expert and author of last year’s SVO: Powering Your Vehicle with Straight Vegetble Oil, called it a "nifty application and a great business idea."

Gregg also drew attention to a strong part of Vegawatt’s pitch: that it won’t require "intervention or maintenance by restaurant staff."
That’s because when users buy a system — or lease it for $450 a month — they get a service contract with the company for cleaning and maintenance.

The owner of the very first Vegawatt, George Carey (pictured above), seems pleased with the unit, too. He heartily endorses the company on its website, saying, "The Vegawatt system enables me to significantly reduce my energy costs, generate clean energy on-site, and very importantly, reduce the heavy energy footprint of my restaurant."

See Also:

•Tapping the Vortex for Green Energy
•Global Energy Network Depends on a Few Vulnerable Nodes
•How A Google Engineer Hacks His Energy Usage
•Biofuel Startup Strives to Meet Obama’s Green Ambitions
•Obama Voices Biofuel Doubts
•Biofuel Solution at Sea, not on Land
•DOE Invests $125 Million in Synthetic Life to Develop Biofuels …
•Food vs. Fuel: Saltwater Crops May Be Key to Solving Earth’s Land …
WiSci 2.0: Alexis Madrigal’s Twitter , Google Reader feed, and project site, Inventing Green: the lost history of American clean tech; Wired Science on Facebook.


Tags: Sustainability

Close Posted by: TR Bob | 01/7/09 | 5:34 pm |
Hats off to James Peret for making something useful with waste cooking oil, other than using it to power diesel powered cars.
Next I would imagine someone capturing all the wasted methane gas from TexMex patrons after a hearty meal of refried beans.

Posted by: Dave Flores | 01/7/09 | 5:40 pm |
Ooops, no more cheap biodiesel, guys!

Posted by: dave | 01/7/09 | 5:58 pm |
Um, the payback calculation is, well, childish. They don’t include the cost for the maintenance contract, or the money you can make selling the oil.

And they don’t say what kind of emissions are produced (other than 50% of the CO2 of a coal plant). There are LOTS of other emissions this thing produces that could be much worse to produce throughout cities everywhere…

Posted by: David | 01/7/09 | 6:12 pm |
That Vegawatt picture is very photoshoped!!
Look at the saturation in the picture and then look at the Vegawatt stickers of sharpness!

Sorry, that’s the nerd in me. Good article, let’s get away from fossil fuels asap!

Posted by: christopher | 01/7/09 | 6:13 pm |
Yeah, but…

…why wouldn’t/couldn’t a restaurant get a fuel oil delivery and then generate its own electricity completely? And why don’t we? I own a furnace, I need hot water, why couldn’t I run a generator instead of a furnace and install baseboards?

I mean, why stop at used oil?

-C

Posted by: andrew | 01/7/09 | 6:15 pm |
@dave

While a story on a blog may have “childish” calculations, it is far superior to some relatively uninformed commenter’s dissnissive approach. How is your suggestion that “other emissions” might be worse than the offset emissions any less childish? Do you have anything stronger than disbelief to support you trollish comment?

Posted by: it's me | 01/7/09 | 6:32 pm |
Capitalism FTW

Posted by: Ross | 01/7/09 | 6:55 pm |
I guess if this things the real deal, it’ll come down to what makes the most economic sense for the business. Selling the oil or using it as fuel to lower your electric bill?

Posted by: Paul | 01/7/09 | 7:02 pm |
10 Points!! Aside from all the noise it must make it’s a great innovation.
There are 2 and 3 stage commercial power plants where a natural gas powered turbine is used to generate electricity with the exhaust going to heat water.
All it needs now is to harness the remaining 30% energy coming out of the exhaust for space heating and/or to run refrigeration via a peroxide cooler and he’s almost at 100% efficiency.
I wish this bloke every success!

Posted by: WarLord | 01/7/09 | 7:17 pm |
Greetings

Good idea but one caveat about the saving. Many regular gen sets use the exhaust heat exchangers to heat water or air. Regular feature in modern Co-Gen.

And yes a modern high efficency gas boiler for resid. baseboard heating can be had with a coil allowing you to heat domestic hot water. Use a solar solution in summer and boiler in winter maybe….

Still a good idea but I’d hope they’d keep things CLEAN and thus safe!

Posted by: Jack | 01/7/09 | 7:38 pm |
Use waste oil to generate electricity and hot water. Great idea. It can reduce the food waster and pollution.
http://www.laptops-battery.co.uk/ibm-thinkpad-t61-battery.htm

Posted by: Michael | 01/7/09 | 7:53 pm |
There is one other down side on this, your bar of soap will cost more, as most soap is made of recycle grease from restaurants and fast food stores

Posted by: Michael | 01/7/09 | 7:55 pm |
There is one other down side on this, your bar of soap will cost more, as most soap is made of recycle grease from restaurants and fast food stores

Posted by: j | 01/7/09 | 9:36 pm |
$1000 a month, at saving of $2.50 per gallon, makes $400 gallons a month.

Assuming they could have sold that oil for 40c a gallon, the lost opportunity is $160.

Note that regardless of leasing or buying it, you receive a contract to service and maintain it. You’re right to point out that they haven’t mentioned the cost of such a contract. Is it free? $100 a month? 10? 50?

Either way, if you estimate a worst case return of $700 savings per month, taking into account maintenence and opportunity cost, you end up with a payback period of ~32 months – 2years, 8 months.

Concerns about the emissions of the generator itself don’t bother me greatly. Once you’re working with a used product, you’re already ahead, since the emissions related to producing the fuel in the first place are no longer counted.

It’s an interesting idea, at the very least.

Posted by: B | 01/8/09 | 12:25 am |
So much for dreams of wandering around restaurants bumming bio-diesel and making your own for next to nothing whilst wearing cut offs with an acoustic out of the case slung over your shoulder.

Now you will have to ride up to the restaurant pump and have them say things like, “Oh sorry dude. It’s December and cold and we use electric heat so there is a deep fryer sludge shortage. Unfortunately the price has gone up man.”.

And so enters the first green middle man.

Isn’t the rule of the game that there is always at least one middle man, definitely at least one tax man, and of course a lot of bad men where there is money to be made?

The future marches on…

Man I sound negative.

*Runs off for a positive sandwich and a glass of juice.

Posted by: Sergio | 01/8/09 | 1:02 am |
Finally bistromatics is invented!

Posted by: Dumpleton Von Snickerpants | 01/8/09 | 1:46 am |
I still prefer Mr. Fusion.

Posted by: Karl Schröter | 01/8/09 | 2:43 am |
BTDT since 2002.

In Germany, people used to pay (a few months ago) up to 1 Euro per liter – that’s almost five US$ per imperial gallon(!) – for used vegetable oil!

Since the oil prices dropped, the price has sunk to about 0,7€/l – that’s probably still more than regular off-the-pump Diesel fuel in some other countries.

Posted by: gwb | 01/8/09 | 6:32 am |
this is typical republican junk. nobody wants to dick around with some piece of grease burning gray metal box. that would take them back to the old coal fired home furnace. Say son would pour some grease in the generator it’s about to run out, and don’t use chinese food grease this time it smells like fish.

Posted by: Homero | 01/8/09 | 7:11 am |
“Let’s bow our heads in prayer. Dear Lord, I know you’re busy, seeing as how you can watch women changing clothes and stuff. But if you help us steal this grease tonight, I promise we’ll donate half the profits to charity.”

–Homer J. Simpson

Posted by: Yves | 01/8/09 | 7:17 am |
Nicely done Peret! Now Sell Sell Sell! Seems like a winning hand.

Posted by: SleepFuriously | 01/8/09 | 7:24 am |
A restaurant in Oceanside CA has been doing this for about 3 years. Using their excess oil to power their refrigerators and freezers. This is a great invention and I’m glad it is spreading.

Posted by: dervheid | 01/8/09 | 7:42 am |
5Kw.
per ?..
hour, day, week? Tell me!
Kw is an INSTANTANEOUS measurement unit. Meaningless in this context without a timebase reference.

Posted by: John Tedder | 01/8/09 | 8:15 am |
I used to own a small restaurant. I had a special dumpster in the parking lot to store the used oil until a big truck came to collect it. Don’t forget to account for the environmental savings of not having a big truck driving around collecting the used oil.
Does the VegaWatt have to run 24/7 to get the $1000 per month savings?

Posted by: muD | 01/8/09 | 9:11 am |
Most of your fast food outlets are independently owned: usually in small regional groups. Most of these guys are looking to save money however they can and this is in the right price range for them to afford. He should do well.

Posted by: mitch | 01/8/09 | 9:39 am |
@gwb
“this is typical republican junk. nobody wants to dick around with some piece of grease burning gray metal box.”

Yes, no one WANTS to do it…that is why a savvy restaurateur would PAY a minimum wage worker to do it.

As ‘it’s me’ said: “Capitalism FTW”

PS: WTF does this have to do with party affiliation?

Posted by: Eric | 01/8/09 | 10:08 am |
@dervheid …

Yes kW is INSTANTANEOUS….
That means that if you run it for an hour, it shaves 5 kWh worth of power from your electric bill.

Watts is power, volts*coulombs/second, you are billed by the kilowatt hour which is a measure of energy…

If you’re gonna act smart at least try to be smart

Posted by: Thinker | 01/8/09 | 11:26 am |
This is fantastic, bravo James Peret, keep up the great work.

Posted by: VICB3 | 01/8/09 | 11:35 am |
Just watch. Some over-earnest enviro true believer will bitch about the Co2 footprint of this thing. Ditto an Air Quality Management Board bureaucrat worring about emmisions.

Posted by: Jason Boatright | 01/8/09 | 11:45 am |
Wow, that is truly amazing. You gotta love it!

jess
http://www.internet-anonymity.net.tc

Posted by: IowaBiodiesel | 01/8/09 | 12:42 pm |
This machine would not be legal in California due to the emissions from that engine. Most restaurants dump a lot of debris into those dumpsters and it would reek havoc on the engine. I hate over simplification, NOTHING is free. UFO is not considered “low level hazardous waste” and trying to get that into my basement, vented to code and abate the noise would prove very problematic. Mid America energy and my insurance underwriter would have a field day.

Posted by: Davoud | 01/8/09 | 12:56 pm |
Why not providing electricity and heat?
The engine produces heat it can be easily used to heat water, which in turn can power radiators.

Posted by: Davoud | 01/8/09 | 12:57 pm |
Why not providing electricity and heat?
The engine produces heat it can be easily used to heat water, which in turn can power radiators.

Posted by: PJ | 01/8/09 | 2:03 pm |
Awesome! More CO2 and particulate matter in our atmosphere.

Posted by: mo | 01/8/09 | 3:16 pm |
in the UK we have to pay for our oil to be collected by a certified waste oil collection company. Long gone are the days when we could sell it.

Posted by: Kirzen | 01/8/09 | 4:38 pm |
5KW Whats?

5KWH?

You have to rate power generation based on power consumed over time, its like saying that your machine can push 500lbs. 500lbs from where to where? How long can it do it? Does it generate 5KW as long as its running? Will it run forever (concievably) on the grease from the kitchen?

Do you realize that 5KWH is worth about 30 CENTS? How could you possibly (as a business) rationalize spending $450 a month on something that (even if its running 24H a day) generates about $7.50 a day? You’d be better off setting up some sort of agreement with the biodiesel folks or the people that clean your frier to dispose of your cooking oil for free, rather than waste over $200 a month on some dude’s pipe dream.

Posted by: Uncle Al | 01/9/09 | 8:47 am |
Combustion rule of thumb: 5 eV for every molecule O2 used. Then 40 KJ/g for pure carbon oxidized to CO2. That said, /_\H(comb) empirical numbers,

coal, -24 to -32 KJ/g
1-dodecanol, -42.266 KJ/g
glyceryl trioleate, -45.3 KJ/g
rapeseed oil, = -40.2 kJ/g (density = 0.92 g/ml)

80 gallons = 302,833 ml = 278,606 g = 1.12×10^7 KJ
[(1.12x10^7 KJ)/(5x10^3 KJ/sec)][(1 min/60 sec)/(7 days) =

5 KW 100% efficient thermal output for 5.3 min/day or 37 min/week. This is a candidate for the Federal Witless Protection Program. The Enviro-whinerism trinity is "expensive, shoddy, deadly".

Posted by: Phoenix Woman | 01/9/09 | 11:25 am |
Peret should target the bigger fast-food chains with this first. They’d love it!

Posted by: Phoenix Woman | 01/9/09 | 11:33 am |
Oh, and how many of the folks commenting bothered to, y’know, Google “Vegawatt” so they could find out more before they started posting about how “noisy” it was? According to the Vegawatt website, it’s a quiet machine

Read More http://www.wired.com/wiredscience/2009/01/vegawatt/#ixzz0vg0APzAT