Energy efficient supermarkets - Ventilation

Energy measurements and energy survey were performed in a Max Hamburger restaurant and nine energy saving measures were proposed. The greatest energy savings are heat recovery of the ventilation air, which is estimated to reduce the total district heating demand by about two thirds. An energy saving of just over 10 % can be obtained by minimizing the operating times of the grills. If all nine measures are implemented, the savings will be about 20 % of the electricity and just under 90 % of the district heating, or 42 % of the total purchased energy.

Measurements have been made in two grocery stores to investigate how the choice of ventilation filter affects the use of electrical energy, the air quality in exhaust air and the indoor environment in the store. The results show the large cost savings can be made both in terms of operation and maintenance (costs for electricity to the fans and costs for filters). The electricity use for fan operation depends on what the system design etc. looks like. For the stores studied, this means a total saving of approximately 6 000 SEK/year respectively 12 000 SEK/year.  

Measurements has been performed in order to verify the energy saving potential for comfort heating and comfort cooling when using recirculated air, compared to ventilation with outdoor air, while a good indoor environment is achieved regarding, among other things, air quality. The results from the measurements showed a large saving potential by using recirculated air, while good air quality was achieved both with and without recirculated air.

In this pre-study we aim to shed the light and different perspectives for actors on how to achieve increased energy efficiency between tenant and landlord by energy contracts or energy agreement. This may lead to increased energy efficiency, better use of energy and reduced environmental impact.

The aim of the feasibility study has been to produce a prioritized compilation of the most important measures for energy efficiency in food premises. The results show that energy efficiency does not have to be expensive - much can be done quickly and at a low cost. Usually no major investment is required in components or equipment.

Large amounts of energy are lost in contaminated extract air from commercial kitchens. The potential energy savings in commercial kitchens, where many energy demanding devices share a limited space, can annually be in the order of 500 kWh per m2. To be able to recover this energy it might be needed to clean the air. In this study we have looked at various types of equipment for heat recovery and techniques for air cleaning.

This study has investigated the question of how the choice of filter classes in the ventilation system affects airborne particle levels in the supermarket. As far as air quality in terms of particulate concentrations in the supermarket air is concerned, the performance of ventilation units is more important than the choice of filter class. A lower filter class reduces the electrical energy use. Over the whole country, in Sweden, this represents a potential saving of about 45 GWh of electricity.

The purpose of the project has been to compile knowledge on how an existing grocery store can be renovated to reduce its energy use so that it approaches zero. Proposals for energy efficiency measures were developed in the categories of refidgeration, ventilation, heating and lighting. If all proposals were implemented, the theoretical savings potential was 60-65 percent.

Read more about: The concept supermarket approaching zero (only in Swedish)

There is a great potential for energy savings in using ventilation systems with recirculated air in stores. The pre-study shows an energy saving of 66 % for heating, 36 % for comfort cooling and 2 % for a vertical cooling counter when using recirculated air compared to outdoor air alone. 

Fat reduction systems in commercial kitchen ventilation have become more common in new projects and also in existing proporties. Benefits for property owners with these are several. Mainly, the treatment of the grease in the smoke duct reduces the risk of fire and odor removal. But from an energy efficiency point of view, fat reduction can also be crucial to enable heat recovery in the ventilation system. 

This report describes how a test methodology was developed based on visits to different commercial kitchens with different combinations of fat reduction systems, meetings with different manufacturers and stakeholders, measurment in the field, preparation of proposals for buildning a test setup, testing and evaluation of a number of different systems. 

Fat reduction systems in commercial kitchen ventilation have become more common in new projects and also in existing proporties. Benefits for property owners with these are several. Mainly, the treatment of the grease in the smoke duct reduces the risk of fire and odor removal. But from an energy efficiency point of view, fat reduction can also be crucial to enable heat recovery in the ventilation system. 

The purpose of the project was to develop a test methodology for measuring and evaluating how fat separation systems in commercial kitchen ventilation can increase the possibility of heat recovery. The purpose was to be able to facilitate comparisons of fat separation systems with regard to efficiency, but also to take into account maintenance needs and safety aspects by developing guidelines for these. 

Energy measurements and energy mapping were performed in restaurants and kitchens at IKEA and six energy-saving measures were proposed. The greatest energy savings are given to a rebuild of the cooling system that can reduce electricity consumption by 40 MWh / year or 6% of the kitchen's total electricity consumption. If all analyzed measures are implemented, the restaurant is estimated to be able to save 14% of the electricity for the kitchen and restaurant.