Energy and Climate

The role of power generation in driving climate change is well accepted and a significant amount of the work at IES aims to develop not only low carbon energy sources like marine, wind and hydropower but also enhance their contribution by managing variability through network friendly machines and energy storage.

An increasingly important aspect of IES's work deals with the potential impact of changing weather patterns on the energy system which include changes in energy resources, efficiencies and demand levels.

Current Research Areas:

• Renewable Resource Assessment
• Climate Change Impacts on Energy Systems
• Lifecycle Carbon Assessment (Carbon Footprint)
• Decarbonising energy supply

This capability is highlighted in a report for the (then) Scottish Executive that examined the match between variable renewable generation and electricity demand. The Matching Renewable Electricity Generation with Demand project was led by Robin Wallace and performed by Dr Thomas Boehme and Jamie Taylor. It was a highly detailed assessment of the spatial and time-series behaviour of wind, wave and tidal stream energy across Scotland and provided insight into the relationships between each resource as well as with demand. Consideration of potential project cost as well as constraints allowed the feasibility of these resources to be examined and a series of technology scenarios to be developed that allowed comparisons to be drawn. The full report is available on the Scottish Government website.

Example time series of wind resources at two locations in January 2003

With funding from the ERSRC Supergen FlexNet consortium, EPSRC and the Kier Watson Trust, IES is extending both the scope of assessment to the UK level as well as also examining the hydro resource in Scotland. Further details of this is given below.

Modelling the UK Wind Power Resource

Building on the Matching study, this work is developing a detailed model of the UK's on- and offshore wind potential. Across such a large area there are major challenges to ensure accuracy at appropriate spatial and temporal scales. This work is using a complex computationally-intensive mesoscale atmospheric model to create long-term time series of wind speed across the UK at a relatively high spatial resolution. This will be sued to explore the implications of high wind penetrations on the UK electricity network.

Modelling the UK Wave and Tidal Stream Resource

Wave and tidal technologies are relatively new when compared to wind and there are some practical problems that need to be addressed such as deployment and survivability. Projecting the marine climate and completing a detailed analysis will allow the potential of this resource to be established, and develop understanding of its role in the future UK energy strategy. The main aim of this project is to develop methods to explore the potentials available in wave and tidal resources in UK waters.

Mapping Scotland's Hydropower Resource

Harnessing renewable energy sources is key to constraining the extent of climate change. Unfortunately, as such sources are derived from climatic conditions may leave them vulnerable to changes in climate. Impacts include changes in the magnitude and timing of resource availability, knock-on consequences for the efficiency and effectiveness of energy extraction and, importantly, implications for their economics. To date, only hydropower has been studied in detail and has been found to be rather sensitive to changes in climate. Research underway at IES is aiming to understand the potential impact on a range of energy resources as well as electricity demand. [More...]

Impact of Climate Change on UK Windpower

The UK is said to possess the largest wind power resource in Europe, and following on from the Kyoto Protocol and the subsequent global agreements to tackle climate change, the UK government has set a target of 20% for the amount of the country's energy to be generated by renewables by 2020, with off- and onshore wind expected to contribute a large part of this percentage. However, it is currently unclear what the impact of the impending climate change on the wind resource will be. The inherent climate dependency of this power source means that small changes in climate could have a disproportionate impact on its economic viability. This project aims to assess these changes in wind speed and explore the potential impact on their economic performance in the UK.

Climate Change and Renewable Technology Portfolios

Renewable technologies are inherently sensitive to climate change since they are designed to harness specific climatic variables. Some are emergent technologies which will take time to develop and become economically viable, by which time marked climate change may have occurred. This project aims to allow renewable resource variability to be reflected within models of the costs and risks associated with different electricity generation technologies and, in doing so, to explore the influence of climate change on renewable energy portfolios and energy security in the UK. The impact of changes in individual generating technologies are being investigated in terms of their contribution to future energy supply diversity and security. This will allow optimal portfolios of generating technologies to be determined under current and future climates.

Impact of Climate Change on Wave Energy

The growing interest in wave energy together with coordinated actions between ocean energy companies and research organisations should lead to large scale wave power deployment. However, in developing sustainable wave power facilities, it is essential to carefully consider the availability of wave resources over space and time. This is particularly true in the context of climate change which could impact plant operation by changing power generation capability or placing a limit on their structure. In this respect, a mesoscale wave climate model off the British Isles is being developed to improve our knowledge of wave climate over the Atlantic Ocean and contribute to a relevant assessment of potential wave energy farm sites under changing climatic conditions.

Assessment of the Impact of Climate Change on Electricity Demand in Thailand

Climate change is expected to lead to changes in ambient temperature, wind speed, humidity, precipitation and cloud cover. As electricity demand is closely influenced by these climatic variables, there is likely to be an impact on demand patterns. The potential impact of future changes in climate on electricity demand can be seen on a daily and seasonal basis through the fluctuation of weather patterns. The magnitude of the impact will depend on the electricity use patterns in the absence of climate change, as well as long-term socio-economic trends. This project has provided a first look at what a changing climate means for electricity demand in Thailand. [Citation...]

Decarbonisation of electricity supplies requires an understanding of where CO₂ emissions arise across the life cycle of electricity generation, transmission and distribution as well as demand. For electricity generation, emissions from burning fossil fuels during operation are well-known but there are also emissions that arise indirectly during extraction and processing of materials, construction, maintenance and decommissioning. This means that 'low carbon' technologies like renewables and nuclear are not entirely carbon-free. Work at IES has been applying life cycle assessment (LCA) methods to assess the energy consumption and CO₂ emissions of a range of new renewable technologies as well as tranmission and distribution networks. These include micro-wind turbines, wave energy converters and tidal current turbines.

Carbon Audits of Marine Energy Converters

In separate studies we have analysed the life cycle energy and CO₂ emissions of the Pelamis wave energy converter manufactured by Pelamis Wave Power (formerly Ocean Power Delivery) and Marine Current Turbine Ltd's Seagen tidal current turbine. Our results suggest that in both cases the energy and carbon intensities have low carbon footprint and are broadly competitive with commercial large wind turbines. The work is being extended to other marine devices as part of Edinburgh's work in the EU Framework 7 project EquiMar. Both pieces of work have won awards from the Institution of Mechanical Engineers (IMechE) and the papers have been made freely downloadable from the websites of the respective journals' .

The analysis for Pelamis was published in the December 2007 issue of IMechE Journal of Power and Energy [Citation...] and received the 2007 IMechE Arthur Charles Main Award for best paper on a power industries subject:

• Energy and carbon audit of an offshore wave energy converter by R.P.M. Parker, G.P. Harrison and J.P. Chick

The analysis for Seagen was published in the the February 2008 edition of the IMechE Journal of Engineering for the Maritime Environment [Citation...] and was awarded the 2008 Professional Engineering Publishing Prize:

• Life cycle assessment of the Seagen marine current turbine by C. A. Douglas, G.P. Harrison and J.P. Chick

Micro-generation is being promoted to lower CO₂ emissions by replacing grid electricity with production from domestic generators. One concern over this drive is that the use of smaller plant could lead to the loss of economies of scale. In part this relates to cost but also life cycle embodied energy and CO₂ emissions. IES conducted a life cycle audit for the SWIFT, a 1.5 kW rooftop-mounted, micro-wind turbine, manufacturered by Edinburgh-based Renewable Devices. The analysis shows that the energy intensity and CO₂ emissions compare well with large wind turbines and are significantly lower than fossil-fuelled generation. [Citation...]

Reducing emission levels and increasing the level of utilisation of renewable energy are two aims of UK energy policy. Work at IES is developing and evaluating novel and proven processes for producing liquid fuels like alcohols from sustainable sources of carbon for which potentially abundant supplies exist. These sources of carbon include CO₂ emitted from power stations and industrial processes as well as Municipal Solid Waste. This approach is a credible alternative to fuel crops for which competition for land and food supply is a well known issue. The main objectives of this work is to explore the potential for such approaches in terms of energy storage, CO₂ abatement and increased renewable energy penetration. [More...]

Group Leader

Dr Gareth Harrison