Learning to live with the environment
“The Building Schools for the Future programme will provide world class learning environments to inspire and engage young minds” is what Gordon Brown said recently about the programme, which sums up its ultimate objective in a single statement.
There has been much speculation about funding, design and construction of new schools which while very important, should not detract from the overall aim to rebuild or renew nearly every secondary school in England. The hope is that by creating schools that are more modern, exciting and inspiring, children will take pride in their school and ultimately their education. It is an aim that is to be applauded.
In order to deliver a modern curriculum, modern schools will need to feature state of the art facilities to provide children of different abilities and backgrounds the stimulus they need. These will mean facilities for science, catering, computing, sports, music and other varied areas.
Design, of course, will be crucial to providing such facilities, but providing them is only half the challenge. Another important consideration must be making these spaces productive. After all, there’s little use in having a school that offers leading facilities if the conditions within that building are not conducive to effective learning and teaching. In addition to excellent design, the things that matter most in making schools productive learning spaces are thermal comfort, air quality and lighting.
Looking at thermal comfort as a consideration, it is not difficult to see how heat gain could become a problem in modern schools unless properly tackled. As a result of Part L, modern buildings will be far better sealed than most old schools, as drafts and air flow will have been reduced, while growing use of IT equipment is adding to temperature gain. In a recent report, building engineer, Buro Happold, pointed out that heat gains of 70 W/sq are not uncommon in a typical classroom with an average space of 55m², 30 students, a teacher, some lighting and a few PCs. This is higher than a typical office where heat gain is usually treated in great detail. When dedicated facilities such as catering or media suites are considered the heat gains could easily escalate.
Teaching unions have passed a motion calling for their members to walk out when temperatures rise about 26ºC, underlining how important a decision providing optimum temperatures will be in modern schools.
At the same time, the Government has committed to make all new schools carbon neutral by 2016. With this in mind, what is clear is that schools will have to emit far less carbon dioxide than they do currently, while still meeting the demands for productive learning environments.
This has led to concern in some quarters of the building services community that decisions for new schools will be made for issues of sustainability and low carbon alone, rather than considering the bigger picture, which also includes productive environments. Onsite wind turbines and photovoltaics may become technology of choice, for example, as these represent the visible and well-know end of low carbon technologies, when actually an alternative technology would better meet overall aims. The concern is not without foundation – when the 2016 target was announced, technologies such as wind turbines, solar power and biomass boilers were specifically listed as examples.
With the twin aims of carbon reduction and delivering productive environments in mind, at Daikin, we believe there is one technology that will prove crucial to creating the schools of the future – air source heat pumps.
Currently, heat pumps are the best technology to deliver energy efficiencies and reduce carbon from heating and cooling and are already widely being used in air conditioning systems in the private sector.
Of the two primary types of heat-pump in use, air source and ground source, at Daikin we believe air source offers the best solution in both the short and long term. As a recent BSRIA report detailed, air-source heat pumps are similar in operation to ground-source heat pumps, except that heat is extracted from the external air rather than the ground. Air-source heat pumps are classified as either air-to-air or air-to-water depending on whether the heat distribution system in the building uses air or water.
The main advantage of air-source heat pumps over ground-source heat pumps is their lower installation cost, which will always be a consideration in PFI partnerships which will be responsible for the most of the BSF schools.
Air-source heat pumps have a number of environmental and operational advantages. For a start, more heat is supplied to the building than energy is consumed by the heat pump.
An air-source heat pump with a COP of three will supply three kilowatts of heat energy for the consumption of one kilowatt of electricity. The latest models boast high values with COPs of up to 4.50 (+5.4%) and EERs of 4.29 (+6.5%), in some instances. If the heat pump is replacing (or being used as an alternative to) electric space heating, the use of the heat pump will offer significant carbon savings.
Moreover, heat pumps open up the option of heat reclamation, which adds further efficiencies. Heat recovery is achieved by diverting exhaust heat from indoor units in cooling mode to areas requiring heating, essentially providing ‘free heating’. However, the primary advantage of heat pump based air conditioning systems is to provide energy efficient heating and cooling with maximum flexibility so the system can be designed according to the needs of the project – a consideration that is becoming increasingly important for reasons of productivity and operational costs, as well as the environment.
As already discussed, in order to achieve the objective of creating inspiring and exciting buildings the design styles for modern schools will likely feature large areas of glazing with attendant high solar heat gains that can only be dissipated by means of air conditioning. The increasing use of electronic equipment raises thermal loadings further still to a point whereby, even in winter, internal temperatures can reach uncomfortable levels. The demand for cooling or heating can also vary considerably throughout the day depending on the number and occupation of pupils on the premises. But end users have come to expect far more than just cooling and heating from their air conditioning.
The ideal modern system must be energy efficient, easy to install, flexible, reliable and user friendly. This is particularly important for schools who will not necessarily be able dedicate a full time facilities manager to make sure systems are working to optimum conditions. Modern air source heat pump air conditioning systems meet all these demands.
With the performance of air source heat pump air conditioning proven and given their suitability to new build and retrofit, the technology can make an important contribution to delivering the low carbon goals for education, while also helping to create productive environments.
With the public sector continuing to invest money in initiatives such as the Building Schools for the Future Programme, it is important that it is looking forward to make sure that it is investing in the most sustainable solutions. The latest air conditioning, drawing on the technology of air source heat pumps has an important role to play, a role that is only set to increase in the future.