The exhaust system in your kitchen is one of those essential pieces of equipment that you must have in order to operate.

And if your hood is like the ones in most restaurants, it has two settings: "on" and "off." When your line is operating at full tilt during the dinner rush, the "on" setting is probably perfect, quickly sending heat and fumes straight from your cooking equipment outside. But what about afternoons or during light lunches? You probably still have the ventilation on but your equipment is not creating nearly as much exhaust.

I don't have to tell you how much energy that hood exhaust in your kitchen is using. Here's a few tips on making sure it's running as efficiently as possible:

Get the system rebalanced. Your exhaust system needs some regular maintenance to run at optimal levels. If too much smoke is building up in your kitchen, or if the system seems like it's on overdrive all the time, a rebalancing by a trained technician is in order. A rebalance ensures the system is keeping the kitchen safe but not sucking up too much energy by working too hard.

Maximize suction. If you're paying to run your kitchen ventilation system, it might as well be pulling as much of the stuff you don't want in your kitchen as possible. To maximize smoke and heat capture, make sure your cooking equipment is pushed all the way up against the wall underneath the hood. This prevents clean air from getting sucked up from behind the equipment and puts the maximum amount of hood over your line. And if your hood doesn't have side panels, you can install them easily and cheaply. Side panels help trap smoke and fumes, making the exhaust system more efficient.

Install a demand ventilation control. If you really want to save some money on kitchen ventilation then a demand control is for you. It senses the cooking volume in your kitchen and adjusts fan speed accordingly. A ventilation control can reduce kitchen exhaust energy usage by 30% -- 50% and can be either ordered with a new exhaust system or installed on an older unit.

Clean and maintain hood filters. The hood filters are the metal squares in the exhaust opening of your ventilation system that catch the grease in air as it gets sucked out. The hood filter plays an important role, since grease buildup can become a dangerous fire risk. As time goes on hood filters become saturated with grease and should be cleaned. The dirtier the filter, the harder your exhaust has to work to suck air through them. Also make sure they are installed correctly (with the baffles, or ridges, in the vertical position) and that there are no gaps between them. Replace damaged filters immediately. Click here for a complete guide to hood filters.

If you happen to be designing a new kitchen, you should account for a few factors in order to maximize ventilation efficiency:

Group heavy cooking equipment together. Whatever you're going to be cooking with the most should all be right next to each other underneath the hood. If you have a single heavy cooking appliance, like a charbroiler, and other lighter cooking equipment, it's a good idea to separate the heavy piece from the lighter pieces and give it a dedicated high volume exhaust. This allows you to run the lighter equipment under a hood that doesn't have to be on full blast all the time.

Create a big overhang. While 4 feet is the industry standard, 5 or 6 feet of hood will capture more smoke and allow you to run your exhaust system more efficiently. Making the kitchen ventilation system energy efficient not only saves you money, it ensures that the exhaust is capturing the maximum amount of smoke and fumes and getting them out of your kitchen.