Carbon Trust cooks up savings
13 May 2015
Results from industry trials conducted by the Carbon Trust demonstrate that improved ventilation in ovens can lead to significant energy efficiency improvements.
According to Carbon Trust figures, ovens are responsible for 35-45% of total site carbon emissions of a bakery.
In a typical direct-fired gas oven around 20% of gas use is wasted when hot air exits the flues, making no contribution to heating bread dough, it said.
Through the use of variable speed drives (VSDs) and sensors, its analysis showed that matching exhaust fans to the volume of gases produced within an oven could provide energy savings of nearly 5%.
This equated to savings of up to £14,000 per site per year, with payback times varying from one to five years depending on the condition of the existing oven, the Carbon Trust said.
To investigate the potential for improvement, the Carbon Trust conducted two trials with Campden BRI and Spooner Industries.
The trials measured gas volumes produced during baking, both from combustion and from the product itself, and the effect on oven efficiency of improved management of flue gas.
“The Carbon Trust project showed that improved exhaust gas control has potential for cost savings,” said Gary Tucker, head of baking and cereal processing at Campden BRI Group.
“This can be implemented by installation of VSD’s to exhaust fans with links to burner fire rate. Further savings are possible by balancing gas flow rates in and out of the oven.”
