The University of Warwick has established a dynamic new research group, Sustainable Energy Engineering Design (SEED) led by Professor Bob Critoph, to undertake research in low carbon energy technologies and design essential to underpin a sustainable built environment.
Sustainable heating and cooling technologies include low-carbon heat driven refrigeration, air conditioning and heat pumping systems, solar heating systems and analytical property measurement of materials used in these technologies.
The facilities cover three areas:
- Thermal Systems Testing
- Analytical Property Measurement Facilities
- Solar Energy Evaluation and Testing
A new environmental chamber enables the evaluation of the thermal performance of heat pump, refrigeration and air conditioning systems as well as building fabric components. The chamber comprises of a large scale guarded hot box calorimeter suitable for measuring accurately the thermal performance of heating and cooling systems and also capable of testing building façade elements of dimensions up to 2m by 2m. The chamber simulates a wide range of operating temperatures and enables the testing of complete systems.
Infra Red Camera
This high specification infra red camera is suitable for characterizing the thermal performance of both large scale building façades, heat stores or solar collectors and small-scale items such as photovoltaic cells or system components with a total area of less than 40 by 40mm.
Equipment for analytical thermal and fluid flow property measurement is available to characterise the thermal and mass transfer properties of new materials that are used in low-carbon heat driven heating and cooling technology.
Thermal conductivity measurement
These facilities can measure the thermal conductivity of liquids and solids to an accuracy of better than 10%. Typical samples have a thickness of 5-50mm and diameter 20-100mm and conductivities can be measured over a temperature range from ambient to 200°C.
A differential scanning calorimeter, compatible with a wide variety of refrigerants, measures the heat capacity of materials. The SEED research group is primarily using the equipment for the measurement of the heat capacity of activated carbon with adsorbed ammonia.
Rubotherm magnetic suspension balances are available to weigh carbon containing adsorbed gases. The balances have electrically heated chambers that allow the mass of adsorbed gas to be measured over a range of temperatures from ambient to 250ºC which can be controlled to with an accuracy of ±0.5ºC. The equipment can operate over a pressure range of 0-100bar.
Phase change materials (PCM) can be used in slurry form for their very effective heat transport properties. An understanding of how PCMs behave in pipe flow and storage is important in system design.
The Kinexus rheometer can be fitted with cone & plate, coaxial cylinder and vane tool measuring systems to allow a large variety of liquids and slurries to be tested over a wide range of temperatures and shear rates.
Fluid flow velocity profiling
Ultrasonic velocity profiling is available, which can non-intrusively measure the velocity profile in flowing liquids. In addition to a wide range of liquids of various viscosities, the system can measure flow profiles in fluids that contain suspensions of micro capsules and materials undergoing phase transition.
A large area (3.2m2) continuous solar simulator allows evaluation of the performance and detailed characterization of solar thermal and photovoltaic systems. The angle of the assembly can be varied from horizontal to vertical in order to investigate the effect of natural convection within thermal collectors.
- Working Area: 1.4m x 2.3m
- Irradiance: 600 - 1200 W/m2
- Spectrum: Air Mass 1.5 (Class A for 500 - 1100nm)
The facilities also include data acquisition and control equipment plus highly instrumented outdoor and laboratory test facilities for complete solar energy systems analysis including commercial systems for domestic use.
The laboratory also offers facilities for testing individual components of solar collectors or assessing the performance of new designs under controlled conditions.
Evacuated Tube Solar Collectors
Detailed experimental characterisation of the performance of medium-sized standard solar thermal systems will provide extensive data from which to predict the utility of solar energy in the UK for heating and cooling applications.
Optical Characterisation Equipment
Research is being undertaken in the areas of solar energy systems and advanced glazing that requires the optical characterisation (reflection and transmittance) of coated glasses and textured or selective surfaces (solar thermal or photovoltaic).
In addition to small single component samples, total transmission can be measured through multiple layered glazing systems or systems that introduce significant levels of light scatter during transmission.The system can accommodate samples of almost any size allowing measurement of transmission and reflectance from large samples.
Solar Radiation Characterisations
Facilities are available for testing solar thermal and photovoltaic collectors and building façade components. The indoor solar test facility uses several different solar simulators and provides carefully controlled conditions. The outdoor test site is used for instantaneous and long term monitoring of solar thermal and photovoltaic systems.
The new Science City sustainable heating and cooling laboratory capability will greatly reduce testing and evaluation time and so increase research productivity. This should help accelerate product development and thereby shorten the concept to market timeframe.