[In partnership with VEI] Innovative ideas often originate unexpectedly. Minor adaptations to existing systems often result in major savings. A good example is the fitting of an intelligent control system in soft drink vending machines. This reduces energy consumption by up to 35%.
Over the past decade, society has become increasingly aware that energy is something that has to be used sparingly. This not only means the efficient generation of electricity from primary fuels such as oil and gas, but that the use of sustainable, often renewable energy sources is also emphasised, as is the limitation of losses. One of the initiatives that can be put in the latter category is the development of an intelligent energy management system for soft drink vending machines.
From 400W to 260W
Soft drink vending machines are found in numerous places; just think of schools, factories, on the street or in railway stations. Such a cooled machine usually consumes approximately 400 W when switched on, with a large part (approximately 180 W) used for lighting (with electronic ballast). The machine does not, however, have to be left on all the time. Energy consumption can then be greatly reduced without affecting quality for the consumers.
An example of such an energy management system is that used by Coca-Cola in its soft drink vending machines. From measurements at Honda Europe, it appeared that a soft drink vending machine consumes around 2,500 kWh of energy each year. To decrease this amount, Honda initially considered switching off the lighting on the front panel, but Coca-Cola ultimately suggested installing their Energy Management System (EMS).
This system responds to the inputs it receives from the installed sensors. It then monitors whether people are in the vicinity of the machine (e.g. using a movement sensor) and how many cans are still in the machine (the lower the volume of drinks to be cooled, the lower the required cooling capacity). The temperature in the space is also often measured and the working of system is matched with this temperature. The customer can also dictate during which periods the machine may be switched off (usually at night). The machine can then, for example, start cooling an hour before a shop opens so the drinks are cold when customers arrive.
Measurements show that this energy management system has a remarkable effect on energy consumption: it can lead to a reduction of 35% with intelligent on/off switching of lighting and cooling intensity control. Considering the large number of such machines (at the end of 2007, for example, Coca-Cola had approximately 70,000 coolers at its customers in Belgium and Luxembourg alone), the use of such an EMS system can significantly reduce energy consumption, the costs of the consumers and the environmental impact.
Besides soft drink vending machines comprising a market for an energy management system, the energy consumption of snack vending machines and hot drinks vending machines can similarly be greatly reduced. It is estimated that for snack vending machines, a reduction of up to 22% is possible, and for hot drinks vending machines up to as much as 39%.
Obviously the use of this EMS system is not all that can be done to reduce the energy consumption of a drinks machine. LED lighting instead of gas-discharge lamps with ballast would, for example, cause a further reduction of energy consumption.
Provinciale ontwikkelingsmaatschappij West-Vlaanderen, Sustainable Enterprise Charter (available online: www.pomwvl.be)
Article courtesy: Electrical engineering department (ESAT)-ELECTA, KU Leuven
Author: Tom Loix