The Problem

McDonalds knew they had a problem with energy consumption and also the reliability of fans in their kitchens. Unreliable equipment was causing many problems including high energy costs and McDonalds was hoping to see 40% energy savings and less wear and tear on the fan, including soft start-up.

Sentridge’s Solution

Sentridge Control working in partnership with the Drive Alliance came up with the solution which was to install 5.5kW ABB HVAC drives. Using the drive’s real-time clock, the fans were made to run at full speed over the busy periods and at 80% speed at other times. This resulted in a 50% saving in energy. On some installations, a boost button allows the fan to be speeded up to its full extraction speed if needed. Another major benefit was the reduced fan noise that this drive method allowed, particularly important to McDonalds at night.

The Full Story

Fifty McDonalds restaurants nationwide are saving 50% on energy bills for kitchen extractor fans with the help of ABB Drives.

Dave Holden, Project Manager, Restaurant Services, for McDonalds, says: “We were updating old equipment and realised we could reduce our carbon footprint by making large fans run more slowly.” Variable speed control was implemented on fan units with large 5.5 kW motors. These now draw about 2kW for most of the time, but have the capacity to boost extract volumes significantly at busy times.
“Variable speed control gives us the extraction volumes we need while cutting energy use. We will also change our specifications to request variable speed control when new equipment is purchased.”

Tried and tested products and services

Although Holden had no particular product in mind, he did want a branded drive that had been proven reliable: “Reliability coupled with a fit-and-forget setup was essential. Our
managers work incredibly hard running successful restaurants and do not want to be troubled with technical equipment unnecessarily.”

ABB Drives Alliance member, Inverter Drive Systems (IDS) in Nottingham has been working with McDonalds for six years and is included in McDonalds’ handbook of recommended suppliers. Sentridge and other ALLiance members have worked alongside them in the ongoing energy project team. Holden has a particular set of requirements for his drives supplier: “We want flexibility, a ‘can-do’ attitude and trust” he says.

Big savings

McDonalds was hoping to see 40% energy savings and less wear and tear on the fan, including soft start-up. The Drives Alliance were asked to look at the application and come up with the correct drive.

The solution…
The solution was 5.5kW ABB HVAC drives. Using the drive’s real-time clock, the fans were made to run at full speed over the busy periods and at 80% speed at other times. This resulted in a 50% saving in energy. On some installations, a boost button allows the fan to be speeded up to its full extraction speed if needed.

Another major benefit was the reduced fan noise that this drive method allowed, particularly important to McDonalds at night.

Variable speed control also cured a problem which was affecting the operation of cooking equipment in the kitchen. In order to contain cooking smells within the kitchen area, McDonalds aim to supply 85% of the air it extracts through air conditioning plant.

High extraction rates were creating an imbalance that meant whenever an external door or window was opened, there was a rush of cold air into the kitchen, affecting the energy consumption of the equipment as it attempted to maintain its cooking temperature.

It also meant the air conditioning was working harder to maintain a comfortable temperature.
Reducing the fan speed has alleviated these problems.

Another advantage for Holden of using an ABB Drive solution was that the setup required no involvement from the restaurant management team. The retrofit work was fitted in around the busy times in the restaurant to avoid disruption. The fan would normally be fitted on one day and changed over in a quiet time the following day, such as mid-morning, or even on the same day when a standby fan was available.

If you’d like some more information, or you’re interested in how Sentridge could help you with your Fan or other applications, please don’t hesitate to get in touch with our team.