Some would say that renewable energy is an exciting new development which holds much promise for the future, critical to the future sustainability of life on the planet. Others might point out that renewable energy is not new – for instance, wood is, and always has been, the biggest source of useful energy to mankind.
At the Institution of Mechanical Engineers, we are interested in engineering developments associated with technologies, new and old, for the benefit of human civilisation. Renewable sources of energy can contribute to a number of goals; most notably, to the need to reduce our emissions of greenhouse gases, and as a contribution to a diverse range of primary energy sources.
Renewables can deliver energy in a range of forms – as a source of heat, in the provision of useful work, or in the production of electricity. As an Institution, we are interested in all of these, but in the Renewable Power Committee, part of the Power Industries Division, we are interested mainly in electricity.
Many might argue that the challenges to be met over the next few decades are exactly what engineers operating at the forefront of technology relish most; indeed, it might be said that this is the reason for them entering the profession in the first place. It will be these inspired young engineers who will meet the challenges and solve the problems of today and tomorrow.
The Renewable Power Committee aims to bring forward and stimulate discussion around the issues inherent in the challenge of these problems.
IMechE’s Renewable Power Committee have contributed to renewable power policy debate for over a decade and organise a programme of conferences, seminars and lectures. We also explore new ways to promote renewable energy inside and outside of IMechE with the vision of improving the world through engineering.
Chairman, Renewable Power Committee
Renewable electricity development
Some of the renewable technologies for producing electricity – the most versatile of all the energy carriers – have been around from the beginning. Armstrong’s development of hydro-electric power at Cragside is a prime example. Hydro-electric power has been adopted for more than 100 years in countries which have little or no fossil-fuel reserves but have the potential for vast water storage facilities. Wind energy has been used as a source of mechanical power for water pumping or milling across the world for centuries and could have been used for electricity production long ago had Faraday’s ideas been developed earlier.
The areas of renewable electricity development which are currently receiving most attention, in the UK certainly, are in the marine sector - whether marine current turbines, wave energy devices or offshore wind farms.
The application of photovoltaic systems has received a boost recently in a number of countries because of the financially-attractive feed-in tariffs.
Biomass for large-scale electricity generation holds much promise, but is not without its challenges in terms of securing affordable and, most importantly, sustainable sources of fuel, along with the challenges of dealing with large volumes of low energy-density and often widely variable fuels.
The EU and the UK have ambitious targets for renewable energy production, much of which will be electricity. In the UK the target is to deliver about one-third of our electricity needs from renewables by 2020. The majority of this is expected to be wind generation – most of it offshore. This will bring in its train the need for back-up capacity, to be available when the wind doesn’t blow.
The objectives of the Renewable Power Committee is to provide an informed perspective, from professional Mechanical Engineers, into the continuing development of the renewable power industry; engaging with engineers, industry, financiers, NGOs and government to promote effective knowledge sharing and technology & policy development.
The Renewable Power Committee will:
- Act with the vision of improving the world through engineering, by looking at all aspects of mechanical engineering relating to renewable power
- Provide a focal point within the Institution for matters relating to renewables in power industries
- Establish and maintain a viewpoint on the value and effect of renewables
- Offer professional opinions to the government and other external organisations
- Promote renewables through conferences, seminars, lectures and discussion meetings
- Represent the Institution at the discussions on renewables of other learned societies
- Encourage collaboration with other committees within IMechE as well as other Institutions
- Involve experienced engineers to ensure the committee represents the state of current knowledge in renewables
- Recommend Institution papers for prizes and awards
The scope of the industry - and hence the committee - ranges from resource assessment, economic viability, environmental impact analysis, project development and financing, manufacturing and technology development to safe commercial operations and maintenance for both power devices and complete plants. This operates at both large scale and at microgeneration levels.
Much of this needs to link in with, and provide a specific renewables focus for, existing specialisms within the Institution.
The scope includes:
- Strategic UK Government and international policy
- Biomass in power generation, co-firing and CHP Schemes, including fuel logistics and handling
- Biogas from landfill and anaerobic digestion
- Recovering power and Power Generation Fuels from waste
- Wave power development and exploitation
- Wind power (onshore and offshore)
- Hydro power expansion (whilst mitigating any adverse effects)
- Tidal power development and exploitation
- Solar power development and exploitation
- Geothermal power development and exploitation
- Infrastructure requirements for renewable power
- Interfacing with other relevant committees
The Challenges ahead for renewable electricity
There are fundamental and inherent conflicts in any engineering design which inevitably lead to compromise; renewable energy technologies are no different in this respect.
Examples of this include:
• Renewable electricity technologies are invariably small-scale compared with conventional forms of electricity production where economies of scale have progressively and relatively easily been captured in their capital cost per MW of capacity for many years. Many renewable energy technologies do not lend themselves to such scale-up
• Most renewable technologies - certainly marine-related types – currently bear relatively higher technological risks compared with proven conventional technologies, albeit such conventional technologies have benefitted from many decades of development and deployment, whilst many renewable technologies are still relatively young
• Many renewable technologies produce intermittent supplies of electricity compared with the almost continuous operating characteristics of conventional, thermal, power stations
• The costs of renewables per MW of capacity are higher, sometimes considerably more so, than conventional plant, with the consequential effect on the cost per MWh of electricity produced. This fundamental characteristic has serious policy and social implications
The Renewable Power Committee aims to bring forward and stimulate discussion around the challenge of these problems and the inherent issues through their range of seminars and lectures.