Rotherham Metropolitan Borough Council. Appendix A. Street Lighting. Sustainable Energy Action Plan

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1 Rotherham Metropolitan Borough Council Appendix A Street Lighting Sustainable Energy Action Plan October 2010

2 Streetpride Service Summary Modern street lighting provides many benefits to the community including reduced road accidents and a reduction in street crime and the fear of it. It stimulates social and economic activity after dark and encourages modal shift towards walking and public transport. It is the policy of Rotherham Borough Council to provide appropriate standards of street lighting for the benefit of the community and road users. Best practice is employed to achieve this objective and the guidance provided in the document Well Lit Highways published by the UK Lighting Board is followed insofar as budgets allow. Budget pressures together with heightened awareness of environmental issues has highlighted the need to review policies to ensure that we provide this service in the most cost effective way whilst paying due regard to the environmental impacts of providing this service. Background There are approximately 38,000 street lighting units in service within the Borough. These range from the 25 metre high masts lighting Centenary Way to 5 metre high units lighting side roads and footpaths. The energy that supplies these units is generated from burning biomass and is called good quality CHP (combined heat and power), and this type of energy fulfils the councils obligation of providing energy in line with its environmental policy. This energy is purchased through a specialist contract organised by the Yorkshire Purchasing Organisation (YPO) on behalf of a number of member Authorities. The contract is the largest of its kind in the country provides a highly competitive rate. The changes in social and economic behaviour which have taken place in recent years have placed an increased emphasis on the provision of good street lighting, particularly in residential streets. The lighting industry has responded by providing efficient light sources and luminaries to provide an effective means of doing so. The types of lamps used in street lighting are generally discharge lamps rather than filament lamps (similar to lights used in peoples homes) and as a consequence these lamps are far more efficient. Typically for side road lighting they are rated between 35 watts and 70 watts and for main road lighting they are rated between 100 and 250 watts depending on the type used (see Appendix 1). This high efficiency is all very well but still translates into a sizeable load when the thousands of units in our streets are aggregated together. The electrical energy used by the street lighting installations in Rotherham is approximately kWh (14.5 million units) pa at current energy prices represents an annual cost in excess of 1.3m, and equates to an average cost of approximately 35 pa per street lighting unit.

3 Reducing the use of electrical energy Some authorities are considering switching off some street lighting and others are considering and/or have trialled schemes of reduced lighting. Careful investigation and consultation should be undertaken in conjunction with these schemes as many towns have extended operating hours and even boast 24 hour cultures in urban areas and good street lighting is essential for people travelling home in safety. The increased use of CCTV cameras to promote public safety has also placed more demands for good lighting as the two combined give the greatest assistance to the police in combating crime and vandalism. Some of the disadvantages in removing or reducing lighting are road safety concerns, increase in the fear of crime and a potential increase in tripping accidents. In addition to switching off street lighting, there are other more socially acceptable ways of reducing the use of electrical energy and these are being actively pursued at the present time. The aim is to strike the correct balance between lighting expectation and need whilst considering environmental and energy issues. It is our intention to explore and utilise all viable options to fulfil this aim. Some of these options are:- 1. The use of energy efficient lanterns using white light Much research has been carried out in recent years into the use of white light in street lighting applications. Traditional installations produce orange/yellow light that is monochromatic and makes colour identification very difficult. White light gives colour definition to the street scene, enables facial recognition, defines the colour of clothing and vehicles etc. all contributing to safety and increasing the feel good factor. It has also been found that the eye is more responsive to white light under low lighting conditions and the British Standard allows a reduction in the lighting level when white light is used. This enables a lower wattage lamp to be used with consequent energy savings. Appendix 1 outlines indicative costs for each light source and wattage sizes used in street lighting applications and from this it can be seen that for estate and side roads, using a compact fluorescent lamp is the most cost effective light source and offers considerable energy savings when compared with alternative types. After early trials of this type of lighting, a report was submitted to an EDS Delegated Powers Meeting on 19 th June 2006 detailing the benefits of this unit and its borough wide use was approved. A capital allocation for lantern replacements enabled around 4000 units of this type to be fitted by 2009 and subsequently the implementation of the 10 year street lighting asset replacement program has allowed a further 4500 to be fitted 18 months into the programme. Continuation of the asset replacement scheme will allow for several thousand more of these units to be utilised in replacing the 9000 identified columns and 10,000 lanterns. The average energy saving for each lamp installed is approximately 10 per year and if all suitable existing units (approximately 25,000 units) were to be changed to this type, the total saving would be 250,000 pa and this would reduce CO 2 emissions by 880 tonnes each year.

4 2. Reduced Lighting (Part Night) Lighting can be reduced by switching selected units off at certain times or by dimming the lighting levels produced. Dimming A report regarding dimming was presented to the cabinet member for regeneration and development and was approved in July This report outlined successful trials of dimming 175 street lighting units in various areas with proposals to increase the number of dimming lanterns by 300 units per annum from 2010, which will save around 5000 pa in energy costs. The significant savings from dimming come with reducing the level of higher wattage lamps on main routes as this also provides the best pay back period. It is not thought to be viable to dim lighting units on residential roads as the lighting is already running at low lighting and energy levels, and the payback period for savings would be in the region of 10 years to cover the cost of installing the dimming equipment. The installation of dimming equipment on the major routes will be fitted as part of lantern changes on asset replacement works and as part of LTP lighting schemes. When white light lanterns are fitted on residential routes, a limited number of lanterns that are removed may be suitable to be refurbished with different components and dimming equipment and be redeployed on main routes. This method of reusing the lanterns benefits by saving energy on consumption and reduces the capital outlay to provide a dimming installation. Switching Off Switching units off is logistically very difficult especially in residential areas and may result in complaints regarding which units are chosen and extensive consultation of residents, where affected, and the emergency services, should be undertaken to identify any potential problems. In spite of this, investigations are underway to look at the possibility of how switching off could be achieved and would be accepted on roads such as distributor routes which have reduced vehicular or pedestrian traffic between 12:00 and 5:30. Depending on the type and wattage of the units which could be considered for a part night switch off (mainly main routes with higher wattage), savings could be in the region of per annum per unit. Initial thoughts are that around 5% of the network could be considered for switching off which would offer significant energy savings, but as mentioned previously consultation and risk assessments will be undertaken prior to any installations being commissioned. Liaison with other similar and neighbouring authorities is being undertaken to ensure a consistent approach will be taken in trialling and implementing any areas of switch off and it is anticipated that trials will be in place by next financial year. 3. Switching and controlling the lights a) Photo electric cells Because of their relatively low cost and reliability, photo electric cells have been used for many years to switch lighting and sign units on at dusk and off again as levels increase in the morning. In the past, units switched on at 70 lux and off at 35 but around 4 years the specification was been changed so that switch on occurs at 55 lux and off at 28 lux. The result is that lamps now switch on later and off a little earlier and several thousand of these are fitted throughout the borough. This saves approximately 30 hours burning time per

5 annum for each unit and ultimately could save kWH equivalent to 10,000 at today s energy prices. Further trials with photocells are ongoing to switch on at even lower levels to save 50 hours per annum which would give a saving of 17,000. b) Electronic Control Gear Older lighting units which are in operation use conventional electro-magnetic control gear which strikes up the discharge lamp and maintains the current in order to keep the lamp lit. The use of electronic control gear which carries out the same operation, gives an energy saving of approximately 5% whilst increasing the life and reliability of the lamp and it has been common practice for several years to fit this in lanterns as standard. 4. Future Technology a) Light Emitting Diodes (LED s) New technical developments are being monitored and appraised to ensure that we are able to take full advantage of new technology. One such technology that is being trialled is lighting produced by LED s and there are 60 of these units installed in Rotherham. They feature low energy usage and also importantly, extremely long life (in excess of 10 years in street lighting applications) which will reduce the number of lighting faults and the need for maintenance. They are expensive at the present time which makes widespread use prohibitive, but volume use will make them more affordable as development continues. It is anticipated that the use of LED units will take over as the main type of lantern fitted as part of the asset replacement capital programme in the next couple of years. Appendix 1 shows the energy consumption of LED units with the potential further savings that could be made. b) Other Energy Sources Solar and wind power is also an option for lighting applications and when LED units become more readily affordable, free standing units without the need for mains connections will be an option worth considering particularly in the more rural areas. Current technology does not provide a self sufficient lighting unit that can operate all night during winter. However, we have a number of interactive signs in use that use this technology and valuable experience is being gained from their use. c) Remote Monitoring and Switching Remote monitoring and switching of street lighting entails the installation of an electronic device at each lighting unit which has the capability to monitor and control the switching or dimming of a unit. There is a trial installation of this system installed along Rawmarsh Road and this will allow the units to be dimmed or even switched off remotely. This will give an opportunity to quickly adjust the lighting and observe the different levels on site. The monitoring device also acts as a meter and will allow for accurate billing of units fitted with such a device. There is an initial cost with the installation of remote monitoring technology which again proves prohibitive but as more are fitted by more local authorities, it is anticipated that the cost of them will reduce and they will offer better value for money and reduced payback periods. Other Issues

6 All lamps used in lighting and sign units are discharge lamps which contain sodium and small amounts of mercury. These are collected and recycled by an accredited company to ensure the environmental impact is minimised. Redundant concrete lighting columns are taken to a crushing plant where they are broken down and the residue used for sub-base etc in construction. Steel and aluminium columns are taken for scrap to be recycled. The specification for new lanterns requires them to be recyclable and redundant units are recycled through a national scheme operated by a company called Lumicom. The recycling of equipment is more environmentally acceptable than disposal, and reuse of recycled materials has been proven to produce less CO2 emissions than producing items from raw materials. We will take the following actions, in so far as budgets allow, minimising energy usage and reducing expenditure and CO 2 emissions. 1. Continue to work with YPO to secure highly competitive energy rates for unmetered supplies on street lighting. 2. Use only high efficiency white light sources like compact fluorescent lamps for side roads in order to save substantial amounts of energy and at the same time provide a safer and more aesthetically pleasing night time environment. 3. Expand the amount of lanterns fitted with dimming equipment, ensuring that existing lanterns are reused where possible. 4. Investigate the validity of switching off street lighting with a view to carrying out trials in April Use photo electric controls optimised to reduce operating hours. 6. Use electronic control gear on all new lantern installations to reduce circuit power. 7. Investigate all opportunities offered by new technology to minimise energy use. Where possible, continue to use Light Emitting Diodes in place of discharge lamps and increase usage as costs of units reduce. 8. Continue trials of and consider the use of remote monitoring and switching systems for future installations. Finally, street lighting is an asset much appreciated by residents as surveys in Rotherham have shown and the continued maintenance and improvement of the asset is necessary to retain public confidence and safety.