Astley Ainslie Hospital Boiler Decentralisation

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1 Astley Ainslie Hospital Boiler Decentralisation Key Objective Our key objectives were primarily to secure and ensure business continuity of heating, hot water, ventilation, catering and associated services at the Astley Ainslie Hospital site. Our objectives went further and were to secure these services in the most sustainable and innovative way by delivering major reductions in energy consumption, greenhouse gas emissions, revenue costs and improved reliability of essential services for patient care. Another objective was to free the bonds and limitations of the site infrastructure so that high value parts of surplus land and property could be made more readily available for sale. The benefits realisation would help to demonstrate that the project ensures NHS Lothian s duties in the requirements of the Public Sector in compliance with the Climate Change Act (Scotland) 2009 and the reporting by Chief Executive of specific HEAT targets relating to energy consumption and carbon dioxide emissions. Brief Description The Astley Ainslie Hospital site had three centralised mains for steam, LTHW and DHW serving in various ways sixteen buildings and their plant rooms via underground ducts. These mains were services by a remotely located boiler house at the SW corner of the site. The physical condition of the mains had reached the point of imminent failure due to their age and having long passed the period of normal operation. The age of the centralised bo ilers was also well beyond normal expected operation and maintenance was becoming a challenge due to obsolescence. In addition the safe operation of this steam plant required a remotely managed alarm panel and shutdown facility at a 24 hour occupied position. The only continuous occupation on site was in a hospital ward and therefore safe operation relied on the input of medical staff who were engaged in their own direct priorities. There was a major challenge in securing finance for this large scale project and the only method available to begin with was from NHS Lothian s own capital allocation and so the project was actually managed over three phases. Each allocation required a business case presented to NHSL s capital investment group. In the latter stages there was an allocation of 90,000 provided from the NHS in Scotland s ECO Hospitals fund. The project was also an integral part of NHS Lothian s carbon management plan approved in 2009 which had a target CO2 reduction of 20% over 5 years.

2 The Project Team The engineering solutions which provided most energy efficient, low carbon, sustainable, lowest revenue costs included the following: Complete removal of all centralised services from boiler plant and the three mains for steam, LTHW and DHW. Heating services supplied by decentralised natural gas fired condensing boilers with fully modulating control of burner, configured N+1. DHW services provided by decentralised natural gas fired hot water generators, configured N+1. DHW services in areas of low demand provided with point of use electric units incorporating percussion taps to enhance efficiency. Separation of heating and DHW providing best opportunity to maximise benefit of condensing boilers and reduced heating circuit temperature. BMS controls throughout, apart from bespoke equipment with integral controllers where BMS limited to status/alarm monitoring, plant on/off via time schedule or positioning setpoint. Inverter control of electrical pumps and motors. Enhanced thermal insulation to service pipes, fittings etc Back up gasoil fired boilers installed where required by overnight patient accommodation. The Project team also investigated the possibility of renewable energy from solar panels and ground source heat pumps building on experience from similar installed projects in NSH Lothian. However under the constraints of capital funding and requirements of revenue payback there was no economic case. The possibility of biomass was discounted at an early stage during to planning restrictions within the City of Edinburgh. Innovation in a Challenging Environment The Project Team has delivered innovative solutions by its inclusive approach to interested parties, not least being to tap the skills and knowledge of staff on site. The challenges were: Financial The provision of services at this hospital have been under question for many years and a consequence of uncertainty has been out of date infrastructure continuing well beyond its sell by date, and therefore investment has been minimal. Applications for major projects such as this would be scrutinised carefully to ensure sound financial investment in the hospital s uncertain life. Contamination Asbestos, oils and chemicals Providing very tight new plant room spaces within buildings with limited footprint available. Conversion of steam supplied catering equipment, hydrotherapy pool heat exchanger and ventilation system heater batteries to LTHW. Working on infrastructure within services of a busy operational hospital. Requirement of no interruption to services to the hospital.

3 Enhanced investment to optimise sustainability The preferred option of separation of heating and domestic hot water plant, the provision of fully modulating condensing boilers, the inclusion of extensive BMS controls would require 150,000 more capital than a like for like replacement raising the required sum to 1,150,000. The NHSL Capital Investment Group adopted the enhanced investment in order to maximise CO2 reduction since it demonstrated a high return on investment and achievement of target saving on revenue, energy and CO2 emissions. Measurement of Outcomes The completion of all works was by end of June 2014, the enhanced boilers and systems having come in to operation in phases in the preceding years. The total capital investment over the three years has been 1,150,000. The measurement of energy and CO2 is externally audited as part of NHS Lothian s accreditation to the Carbon Trust Standard, and the following are taken from these verified figures and are based on a comparison of 2012/13 with 2014/15: Gas consumption reduced from 16,378 to 8,730MWh representing a saving of 47% At today s tariff this is equivalent to 295,000 per year. Electricity consumption has reduced from 2,799 to 2,621MWh At today s tariff this is equivalent to 21,000 per year. CO2 emissions savings are 1,565 tonnes per year and equivalent to reduction in CRC costs of 24,000. Environmental improvement will be evidenced by the removal of the contaminated boilerhouse and high chimney. Noise levels from the old boilerhouse are removed completely to the relief of local residents who have complained frequently in the past. Damage to building fabric due to leaks from fractures of steam and condensate mains have been removed. Water consumption from the supply to the central boilerhouse has reduced by 7,000m3 per year, yielding further annual revenue saving of 12,000. The old plant was unreliable and costly to maintain with constant threat to site business continuity these threats are now greatly diminished, evidenced by minimal interruptions and reduced call outs for estates staff. The hospitals heating and hot water services have been secured for the remaining life of the Hospital at its present location. A real sense of ownership by our estates staff has been a source of encouragement and motivation which help to promote further quality investment and more savings in energy, CO2 emissions and revenue. The total revenue savings, indicated above and which exclude maintenance savings are 352,000. When a full 12 months operation of the new plant is assessed this saving will increase to 380,000 and show a simple payback of about 3 years. Transferability of Project to Other Parts of NHS

4 This project has demonstrated that investment in higher quality engineering systems can produce significant benefits to sustainable development and help to secure a better future with lower revenue costs to NHSL and more funds released for direct patient care. The heating boiler plant in each location was supplied by Broag Remeha, meeting operational requirements of low maintenance, reliability and ease of use. The fully modulating and self contained control systems provide very good energy efficient operation. The gas fired domestic hot water plant selected was supplied by Andrews Water Heaters, The multi burner operation and reliability being of significant benefit.

5 The BMS controls were supplied by Schneider and incorporated in to the Sigma system already in use at about 30% of NHS Lothian s footprint. Point of use electric water heaters were supplied by ZIP heaters and are proving operationally reliable, effective and energy efficient.

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