PUF AV: A Day at Georgia Power's Customer Resource Center

Public Utilities Fortnightly visited Georgia Power's Atlanta Customer Resource Center on October 10. It's an amazing place where industrial and commercial customers can see their future and test out the best equipment on the market for their businesses.

Electric Griddle

They will have different temperatures per tray. Mine's a three-tray unit I have back here. So, I could cook at 500, 300, and 100.

In the restaurant industry, they kind of design their whole menu around any temperature and the different times. We have that piece of equipment.

How do we promote the electric griddle? Well, when we serpentine an element on here, we cover more surface space than a gas one does. We're going to have less temperature differential on this plate.

Now, if you're Waffle House, that doesn't work, right? Waffle House, you ever seen them? They like to cook and like to hold. We wouldn't go show them an electric griddle.

For somebody spitting burgers out every day, and doing eighty percent of their business in two hours, we want to show them the more productive piece of equipment.

Fryers

Fifty dollars a vat, right, the year's savings. That's what we talk about when we talk about fryers.

They're more productive on the electric side. Every piece of equipment you see here comes in gas. There's a gas alternative. Every piece of electrical equipment is more efficient than its counterpart in gas, probably on average about twenty to twenty-five percent.

Maintenance

We talk about equipment, we don't talk about measuring the plug, load, and then measuring the pipe. We talk about the system impact of that equipment.

So, maintenance is a big part of this. There's a lot of moving parts on gas. You've got to have the burner. You've got to have the air flow. You've got to have the gas pressure and all that. Electric is much simpler, much more longevity, less maintenance. So those are the things we talk about if somebody came in to our place to talk about the electric advantage.

Snow Melt

We want to address things at what I call the snow melt, up top, and let it come down. Our next venture, which is very important to the other utilities out there is to prop up what we call the Electric Foodservice Council, where electric utilities come together with manufacturers of this equipment to address the change. If any utility guys are listening out there, let's go together. Let's approach these customers together. Much more effective.

Induction

Have a flame, a conducted flame, or an electric range element that's conducting heat. We're actually, through induction, heating the pan itself, internally, which heats the product. Therefore, the only reason the surface gets hot is because the pan got hot, the exact opposite of conduction.

Tractor Trailer

A tractor trailer refrigeration unit. You see them, they mount on the front of the trailer. Next time you're out on the freeway, see these big trucks.

You might notice these things on the front of the trailer. Its purpose is to refrigerate or freeze and maintain temperature in the trailer. That truck is shipping frozen goods, refrigerated goods, those kinds of things.

It's powered by a diesel engine. What sets this one apart is the diesel engine actually turns a generator, and the refrigeration part of the system is electric. But it's powered by this generator when that truck's going down the road.

What that means, when this thing is parked (a lot of times these trucks are parked for hours), the truck pulls into a distribution center. They may load that truck during the night. The driver with the tractor shows up 6:00 a.m. and hooks up, pulls that trailer out, and he heads off across country.

Well, if this thing is sitting for two, three, four, five hours, that engine is going to have to run. You got a diesel engine sitting there idling, running, that's emitting emissions, it's using diesel fuel, it's putting runtime hours on the engine. It's just a like a car, you got to maintain it, and it's noisy, so if there are residential areas nearby, it could be a factor. You may have half a dozen of these trucks sitting out there running.

Hybrid Unit

The unit is called a hybrid unit because the diesel engine doesn't power the refrigeration equipment directly. It powers that generator.

So, you shut the diesel engine off and connect this to, say, shore power, you can call it. And it will operate that electrically.

So, it's much cheaper to run this on electricity than diesel fuel. It's very quiet. There's no emissions. There's less run time. Wear and tear on that diesel engine. It just makes perfect sense to do that.

So, the reason we have this here in our facility is we want to educate our customers who are in that kind of business, about this capability. Most of the smaller truck refrigeration units are already equipped to do this. The large units like this, it's typically an option, an extra cost option, to get the hybrid capability.

A lot of folks may have it. They don't even know they have it.

SafeConnect

When the
trailer is parked, this thing is sitting there, and they can plug it in. This is called the SafeConnect.

Which if you think about, you've got a 480-volt three-phase power connector out in a parking lot. It might be raining. It might be a puddle of water. That driver may show up in the morning and he hasn't had his cup of coffee yet. He's not thinking. He may forget to unplug this thing, and pull that trailer away.

So, this thing is designed to take care of those kinds of situations safely. It's called a SafeConnect. It's got a device here that when if you pull on this, it releases the connector. It also detects the loss of continuity. It shuts itself off instantly.{C}{C}

Heat Pumps

What you see in here is a state of the art heat pump or HVAC equipment. This display, it's to illustrate all of the little details that need to be taken care of, if you're building a house or a small commercial building, to improve the energy efficiency of that building.

All of these units are operational. We turn them on, you can hear them run.

This is a dual fuel system. We don't have a gas connection to it, but it's designed to run on gas or electric. It's a high-efficiency heat pump, as well as a gas furnace. This unit and that one and this one over here, these are all what we call "variable refrigerant flow," VRF systems. I don't know if you're familiar with VRF.

What a variable refrigerant flow system can do is replace multiple zone systems with one system. The way it works is it can send the refrigerant, either hot gas or compressed.

Each coil in each area can either be an evaporator or a condenser. You can either heat or cool each zone with one system. It's all automatically controlled.

Water Heaters

Plenty of different types of electric water heaters. There's a couple of them here that aren't connected up, as you can see. But the rest of them are all operational.

This is a heat pump water heater. Then down here we have an electric resistance water heater. Then a couple more heat pump water heaters down there. This little gray box on the wall is a tankless electric water heater.

And they all have applications, advantages and disadvantages. That's why we have all of these here. So that we can discuss with our customers. 

The best application for this is in an environment where there's a lot of heat and humidity. Think about what kind of environment would have a lot of heat and humidity. A kitchen maybe.

Think about a school system. You go visit your kids at the elementary school. If you could go back in the kitchen, you'd see all this cooking equipment. There'd be a lot of activity. They wash a lot of dishes. It's hot back there. It's humid. They need a lot of hot water.

This thing's perfect for that application. Because it's going to take heat from surroundings, and put it in that tank of water.

Infrared Ovens

The reason we have it is because most of our customers have these. What we're trying to help them decide is whether or not adding an infrared oven to their convection oven would make sense.

If you peek inside there, you'll see some infrared heaters that are actually inside the oven. That would be a type of way to apply infrared heating in an industrial process.

If they don't have room to add a separate oven outside their convection oven, maybe the heaters can go inside. They work just fine in there.

The concept there is, if you've got an oven that will provide curing on a product in twenty minutes at a certain temperature, what if that customer wants to cut that time in half? They want to double their productivity. Well, they're going to have to boost that system somehow. Either make their oven twice as long, or boost it maybe with an infrared add on.

How Infrared Works

Convection is faster. Infrared is much faster.

Now, induction is not heat transferred. It's not one of the three forms of heat transfer. It's the transfer of energy using an electromagnetic field.

That field is created with a coil. When he showed you that demonstration, the coil was underneath that cooktop. You couldn't see it. It's a flat coil. But it was in there.

If you think about, a long time ago in school, did you ever do an experiment where you made an electromagnet? Take an insulated wire and wrap it around a nail. Then you connect it to a battery, and you've got a magnet, and it has a North pole and a South pole.

Then, if you take those leads on that battery and switch them, then you create another magnet, electromagnet. But now your North pole and your South pole have switched.

If you could take those leads on that battery and switch them back and forth really, really fast, what do you think might happen to that nail? It'd heat up.

Why does it get hot? The reason it gets hot is when that nail is in that magnetic field, and there's a North pole and a South pole, the polarity of that field wants to push the electrons in the metal in a direction. If you reverse your North pole and your South pole, then those electrons are pushed back another way.

If you do that fast enough, then you're causing electrons to move back and forth in the metal, in the nail, and that's an electric current.

Slot Furnaces

We are using a gas fired furnace called a slot furnace to heat these up. A slot furnace is just an insulated box with a great big gas burner on it. Operates at about twenty-five hundred degrees, but it has an open slot.

These bars - kind of like blacksmith technology honestly - these bars are inserted in that slot and they stay in there long enough to get red hot. They actually had a system, a rail system, where they'd load these bars in and they'd kind of roll down.

They would take them off the bottom, when they're hot, and put it in their forging press and form the end of the bar. Well, that heating process took about twenty minutes in the slot furnace.

But the big problem they had with that process, it was very inefficient. It was about ten percent efficient by our best estimate.

When they were heating metal bars, and the other negative to that process, was that furnace was pretty much left on all the time. Because these high temperature furnaces have a refractory lining. They don't like to be thermally-cycled.

It destroys the lining, causes it to crack. And then it's expensive to rebuild the furnace. So, they leave the furnace on all the time.

When they're not heating bars, what's the efficiency of that process? Zero. It's just wasting energy.

Not only that, but if you think about a process inside a plant that is ten percent efficient, well, it's ninety percent of the energy that it's consuming, is going where? Either out the exhaust, or out into the plant.

It was a very hot area to be working in. It was unpleasant. Nobody wanted that job.

They wanted a better way to do it. And they asked us to offer suggestions. We said, well, you really need to look at induction.

Water Cooling AC

Remember, I said, you got to switch those leads really fast. This operates at about eight kilohertz. So, the current flowing through this coil reverses at about eight kilohertz.

I've also got a timer set. Because if I didn't turn the thing off at the right time, we would melt the bar. I want to demonstrate this for you.

You can see we're in an air-conditioned building. The unit's not even on. There's nothing has to be pre-heated. Don't have to keep it on all the time.

It is water-cooled. I'm gonna start my water cooling system, and then my controls boot up in just a few seconds and it's ready to go.

Now I'm not heating the part yet. I have to energize the coil. When I do that, you'll hear it because we can hear eight kilohertz.

This is a thermometer. It's a digital infrared thermometer. It's looking at the [metal] bar.

Right now, it says the surface of that bar is 77 degrees. If you keep an eye on that, you can see how quickly we can heat that bar. It can barely keep up.

That's the surface of the bar. Now the core of the bar is not that hot. It takes a little bit of time.

Ideally, we would heat this thing to about fifteen hundred degrees, and hold it for a few seconds to get it thoroughly heated. Then we would take the bar and go into our forging machine.

But I've just got it ... When we get close to 1,500, it times out. We use 27.6% of 50 kilowatts. And we operate it for twenty-eight seconds.

If you do the math, you can see how many kilowatt-hours we used. Not very much.

Electric Pizza Ovens

Can heat the stone up to whatever temperature you want. Let's say six hundred degrees. And your air temperature up here can be eight hundred degrees. Why would you want to do that? Or why would you even want this thing?

If you think about, if you go to a high-end Italian restaurant, and you're going to pay a lot of money for a pizza, that restaurant probably has a chef that is a career chef. He knows what he's doing. He knows how to cook pizza.

And if you go to one of those places where they have the brick oven type pizza ovens, that brick oven is probably a gas-fired oven. It's got a stone at the bottom. It's got a dome, and the air up there is heated, and it's all heated with this gas flame. 

That chef knows, he puts his pizza in with this big spatula, like those things, and he puts it on that stone, and he knows exactly how long to leave it on that stone to get the crust just right. And then he picks it up and he holds it in that dome where that super-heated air is, to sear all the toppings. And he has the skill to do that. He'll make a perfect pizza, and they're great. 

But what if you're running a Pizza Hut and you're hiring high school kids. These high school kids work for you for about a year, maybe if you're lucky. You're retraining these guys all the time. They're not going to have the skills that this career chef had. But you've got to make a lot of pizzas, and you want good quality.

Well, this kind of oven can do that, operated by someone with almost no skills. Because all you got to do is know what set points, and know how long to leave the pizza in there. That's really all they need to know.>