Profiling energy use and efficiency in restaurants

Abstract

This study has investigated the energy performance of four typical restaurants in Malta. Refrigeration accounted for the highest share of 40% electricity consumption, followed by kitchen exhaust ventilation, domestic hot water and space cooling, which accounted for about 50%, while lighting consumed only 6%. Energy saving potential was primarily identified for refrigeration, water heating and air-conditioning. Although, the fuel sources used for cooking equipment, i.e. liquified petroleum gas or natural wood, accounted for more than 50% of the overall energy used in these restaurants, electricity is the fuel of primary concern given that it is the main CO2 emitter (70% on average of total CO2 emissions in the restaurants) and also resulted in the highest operational cost. The total potential of CO2 emissions savings was found to be 17%, when the recommended energy efficiency measures are applied. One interesting outcome was that the best energy efficiency measure did not yield the best economic feasibility. Upgrading to energy efficient LED lighting provided the best payback period of less than two years, despite lighting contributing to only 6% of the total electric energy. In contrast, upgrades of refrigeration and space cooling equipment resulted in payback periods of more than 15 years and therefore require incentives to make them financially feasible. The installation of heat pump dishwashers can be feasible but require custom-made solutions depending on the hot water demand. Given the high pay-back periods for many retrofit measures, restaurateurs must prioritise simple energy management solutions to reduce operational energy costs. A number of these measures have been identified such as timing of opening of freezers and food preparation scheduling, switching off air-conditioners when restaurant is closed and creating separate air zoning between kitchens and dining areas. A benchmark of 14.51 kWh primary energy per person served was established for energyefficient restaurants.