Conserving energy

Follow these top tips to conserve energy in your business.

In the office | In the factory

• Do you know how much energy you are using? Do you know how much it is costing your business?   Checking your energy usage when the site is not being fully used (e.g. overnight or during shutdowns) is a good way of identifying some of the wastage, for example equipment, lighting and heating that has been left on.
• Is equipment switched off when it is not in use?  Do you know how much it is costing your business? Checking your energy usage when the site is not being fully used (e.g. overnight or during shutdowns) is a good way of identifying some of the wastage, for example equipment, lighting and heating that has been left on.
• Have you an overall master switch to turn the power off on non-essential equipment at night/weekends?  It has been estimated that companies waste up to €6,000 per annum by not switching off equipment when they could.
• Do you have a preventative maintenance programme for equipment?  Have preventative maintenance programmes for equipment such as motors, fans, conveyors and other process plant?
• Are the motors high efficiency models?  Inefficient motors can add 5% to your energy bills. Did you know that idling motors can use up to 40% of the full-load power?
• Do your motors (for example on conveyors, lifts, air extraction fans etc.) have variable speed drives (VSDs)?  These allow motors to receive just the right amount of power to match the load they are under, hence reducing energy use.
• Does your organisation always repair old motors?  Whilst cheaper in the short term, this can mean that a less efficient motor is being used and one that is often less reliable. VSD's can often be retrofitted to older motors to make them more efficient.
• Do you ensure that refrigeration and freezer units are set to the maximum temperature recommended?  Every 1°C lower on the temperature can result in operating costs rising by 2 to 4%. Ensure that doors are kept closed whenever possible. It costs approximately £6 for every hour that a freezer door is left open.
• Is refrigeration equipment well ventilated?  Ideally compressors and their radiators should vent outside or at least have good clearance around them. Overheating of equipment creates extra energy demand.
• Do you check for compressed air leaks?  Checking for leaks can save 30% of the associated energy costs. You should also avoid dead-ends in your compressed air network as this reduces efficiency also.
• Have you checked the operating pressure of the compressed air system?  A reduction of just 1 bar (15psi) will reduce operating costs by up to 7%.
• Have you looked at the alternatives to compressed air, such as physical clean down or washing?  Compressed air can cost up to 50 pence per kWh compared with 5 pence for 'normal' electricity and hence is not an efficient way of cleaning down workbenches and floors!
• Have you installed power-factor correction equipment on your power supply if you have a PF rating of below 0.8?  Some electrical current can work against useful supply, hence increasing costs. PFC equipment normally reduces energy consumption by around 5 to 8% where not previously fitted and usually pays back in 12 to 18 months.
• Are your boilers the latest highest efficiency (HE) condensing type (Class A)?  These are typically 94% + efficient and far more economical than other boilers.
• Have you looked into the possibility of using combined heat and power (CHP) plant?  To make this efficient requires a need for large amounts of heat as well as electricity, for example as in a hotel or hospital. Sometimes this heat can be used elsewhere - for example to heat a neighbouring factory or swimming pool.
• Does your organisation have large workshops or warehouses which are difficult to heat?  Have you considered installing radiant heat tubes? These produce infrared heat radiant heat which is directed to where it is required using reflectors. The heat is able to pass through the air without heating it so that only the staff feel the benefits directly.
• Are automatic and rapid-closing roller shutter doors fitted in workshops and warehouses?  These avoid large doors being left open for long periods and hence the need for additional heating.
• Do you keep sky lights and windows clean to make the best use of natural daylight?  The use of sky lights can help reduce lighting costs, especially in summer. In areas with sky lights and good window light, lighting circuits an be connected to ambient light sensors (photocells) which will switch the lights on only as light levels fall below an acceptable level.
• Do you make sure you use efficient lighting?  Do you make sure you use efficient florescent (T8 or ideally super slim T5 types) or metal halide and sodium high intensity discharge (HID) lights in the factory/warehouse?
• Do you use any other types of lighting control other than simple on-off switches?  For intermittently used areas (such as some parts of warehouses) lights could be connected to occupancy sensors (PIRs) to prevent lights being left on.
• For slow response lighting, e.g. metal halides in warehouses, timer controls are preferable.  These ensure that lights aren't left on out of occupancy hours but remain on during working hours.
• For areas with lots of lighting, zoning should be provided.  Then only the areas in use are lit rather than the whole building!
• For external security lights, photocell light sensors can be combined with PIRs.  These can be used to switch lights on at night and only when movement is detected

Need information, advice or support? Contact us on 1850-green1 (1850 473361) (helpline is available Monday to Friday between 09:00 and 17:00). Eligible companies may also submit a request for a free Resource Efficiency Audit. It is recommended that companies register and use the audit tools prior to requesting a Resource Efficiency Audit.