Introduction
Scotland has been an oil and offshore natural gas producer for over forty years. However, in the recent years, Scotland has had a significant increase in the annual total electricity generated from renewable sources. Renewable electricity generated in 2009 was about 27.4% of the total electricity consumption. This was a major increase compared to 2006 when the gross electricity consumption from renewable sources was about 16.9% of the total (The Scottish Government (a) 1). Wind energy is the most exploited source of renewable energy in Scotland. Overall; wind, solar as well as wave energy production increased by 37% in 2009 (Green Investing 1). It is has the leading deepwater offshore wind technology in the world in areas of installation and maintenance. This has been attributed by the developments in the energy sector as well as the changing expectations of the country leading to exploitation of offshore winds. According to the government, the country should achieve 31% gross energy consumption from renewable energy by 2011 (Scottish Power Transmission Ltd 3) and 80% by 2020 (The Scottish Government (a) 1).
History of Energy Renewable Sources
Exploitation of natural renewable sources of energy began in the mid 20th Century when hydro energy was first exploited. Scotland’s Renewables Obligations which gives the government the mandate to pursue renewable energy objectives was established in April 2002. Britain operated a central national grid until 1990 when the Central Electricity Generating Board broke up leading to the formation of the Scottish national grid for Scotland (Winter 728). The Renewables Obligation Scotland operates to ensure that electricity suppliers in Scotland integrate eligible renewable energy with the non-renewable energy whenever they supply their customers (The Scottish Government (b) 1). Between 2000 and 2002, electricity generation from renewable sources was about 10% of the gross production and largely consisted of hydropower sources.
Electricity Demand Growth
The Scottish electricity demand is expected to be constant between 2010 and 2015 as a result of the global downturn experienced in 2009. However, during 2015 to 2020, the demand is expected to maintain an annual increase of about 0.6% due to increased energy efficiency. After 2020, the electricity demand is expected to increase at about 0.8% in the period of 2020-2025 and thereafter, 1.3% annually over the period of 2025-2030 (Edberg and Naish 16).
Reasons for adoption of Renewable Energy
The development of renewable energy was prompted by the need to tackle climate change and to meet national as well as international targets; to achieve sustainable energy supplies; to encourage development of technologies in the energy industry; and to meet the increasing demand for energy.
According to the Minister for Environment, Michael Russell, Scotland has to act locally to help contribute towards combating the global climate change (Edinburgh University 3). Over the last forty years, North Scotland has increasingly become wet and the rivers have continued to rise during winter; an indication of global climate change and its impacts on Scotland. Floods have also increased in Scotland. Adoption of renewable energy is part of the government’s plan for achieving sustainable environmental management. The government aims to achieve a reduction of its carbon emissions by 80% come 2050 (Edinburgh University 5). It plans to achieve 40% increase in electricity consumption from renewable sources by 2020 (RSPB Scotland, WWF Scotland and FoE Scotland 4). According to the government, this implies that Scotland has to reduce the energy it consumes and rely more electricity from renewable sources. Therefore Scotland has to exploit its renewable resources which are also carbon sinks in order to achieve low carbon emission. This action will also contribute towards the UK’s overall CO2 reduction plan which aims to achieve a reduction of over 60% by 2050 (Edinburgh University 6). According to RSPB Scotland, WWF Scotland and FoE Scotland (2006 3) the government aims to achieve energy efficiency through the adoption of renewable energy so as to enable them cut the emissions that enhance climate change. This will as also enable the government avoid the risks as well as long-term issues which are normally associated with nuclear energy.
The government also considers renewable energy to be the solution to the increasing demands for electricity which has caused the impending closure of the fossil fuel as well as nuclear power generating plants. The fossil fuels and uranium deposits have been decreasing and their continued use have compromised environmental sustainability (RSPB Scotland, WWF Scotland and FoE Scotland 3). It is also estimated that Scotland’s Coal power plants will be closed down in the next two decades. Scotland’s two nuclear plants, Torness and Hunterston B are also due to close. Hunterston B is expected to close later this year while Torness is due to close in 2021 unless extension of their operations is considered (RSPB Scotland, WWF Scotland and FoE Scotland 5). The government acknowledges that the only way to fill the gap that will be created by the loss of nuclear energy without adding more emissions is through renewable energy. In 2002, energy production from nuclear power was 32%, coal was 31% and gas was 26% (RSPB Scotland, WWF Scotland and FoE Scotland 5). This implies that the government has to increase energy production from renewable sources to meet the energy demands for its economy.
Adoption of renewable energy is also seen as potential to creating jobs in developing the renewable technologies as well as in installation of the infrastructure for the renewable energy (Scottish Executive (a) 5). Development of offshore and onshore wind technologies would require great innovations which will create vacancies for more man power. It is predicted that the offshore wind industry alone will create about 28,000 direct jobs (The Scottish Government (b) 3). This would have positive economic contributions to the country’s economy. Besides, research and empirical evidence shows that Scotland has a large potential for renewable energy sources which can be tapped to sustainably meet the current demands as well as that of the future (The Scottish Government (b) 3). Scotland’s energy industry has diverse natural resources including oil and gas fields in the North Sea as well as various sources of renewable energy sources. Besides, Scotland has the expertise and a range of energy resources which maintains the high quality energy needed in Scotland.
Suitable Renewable Energy Sources
The offshore wind energy will be installed in Aberdeen and Shire regions. Offshore winds have capacity of 25GW and energy potential of 82TWh. Onshore wind on the other hand is widespread across Scotland and is also cost-effective to produce. Onshore wind is estimated to have the capacity to produce about 45TWh which is approximately the same as the total projected electricity demands in 2020 (Scottish Executive (b) 9). Wave and tidal energy resources also have huge potential resources with capacities of 14GW and 7.5GW respectively. The country requires about 3GW in meeting its target for 2020 (RSPB Scotland, WWF Scotland and FoE Scotland 7).
Demand Management for Renewable Energy Generation
The need for more electricity generation while ensuring non-emission of Carbon dioxide has compelled the government to rethink its strategies towards energy generation. It is expected that the increase in electricity demand will be about 1% per year (RSPB Scotland, WWF Scotland and FoE Scotland 5). Based on these expectations, the government has developed its target for electricity generation for 2015, 2020, 2030 and 2050. The government estimates that by 2020, the energy from renewable sources should be able to contribute 17.2TWh which requires that it installs 6GW renewable plants (RSPB Scotland, WWF Scotland and FoE Scotland 5). These are expected to come mainly from wind, tidal, wave and other renewable energy sources which have smaller energy potentialities within Scotland. The government has established planning consent before any construction of any renewable generation plant. By 2010, the total installed wind energy capacity was about 3.5GW which is well above the target set for 2010 from renewable energy (RSPB Scotland, WWF Scotland and FoE Scotland 5). The future of electricity generation in Scotland takes into account new technical developments, the future energy prices, the electricity demands as well as the regulatory environment (Edberg & Naish 27).
Generation of electricity from renewable sources to meet the energy demands takes into considerations the location of the electricity supply infrastructure. The energy resource being generated must have a corresponding electricity network to allow as well as to deliver the energy.
The government is committed to filling the gaps that will be created by the abandonment of its major electricity generating power plants which generate electricity from natural gas, coal and nuclear energy. The government plans to close down Hunterston B, a major nuclear energy producing plant this year and is also planning to close down its two coal energy producing plants by 2015. It is therefore considering various options including non-renewable energy. According to RSPB Scotland, WWF Scotland and FoE Scotland (5) the government is considering the use of carbon reducing technologies in its existing fossil fuel power plants as it continuous to develop its renewable technology. Carbon reducing technologies such as the use of carbon capture at its fossil fuel power plants will be used to provide short-term and medium-term solutions to its electricity demand. The government is committed to achieving energy efficiency while tackling fuel poverty.
Efforts to meet the energy demands also take into considerations their environmental influences in areas where the technologies are considered economically viable. The government has implemented a policy framework that guides the economic, social as well as environmental costs of distributing energy (University of Edinburgh 23). This policy ensures the use of variety of technologies which can help achieve environmental sustainability (RSPB Scotland, WWF Scotland and FoE Scotland 8). The strategic approach takes into considerations the sensitive areas. The energy industry is also committed to addressing any technical as well as economic limitations that may arise from the intermittent nature of particular renewable sources such as wind. The industry plans to establish wind generating power plants in different locations while integrating the technology with other renewables technologies (RSPB Scotland, WWF Scotland and FoE Scotland 8).
The energy industry has also focused on energy demand reduction by encouraging energy saving and efficiency as well as adoption of micro-renewables. The industry predicts that the industry will witness a reduction of 0.5% between 2012 and 2013 followed by 1% reduction up to 2020. This will amount to 7.7% demand reduction by 2020 (Gardner 10). The government also encourages investment in energy micro-generation to help meet the energy demands. This will include the use of solar photovoltaics, heat pumps, Micro-CHP, roof-top wind turbines among others. This will enable individuals better meet their energy demands while ensuring energy efficiency. Excess electricity generated from the micro-generation can be transmitted to the national grid (RSPB Scotland, WWF Scotland and FoE Scotland 7). According to the Scottish Executive Development Department (2) there has been an increasing awareness of the benefits associated with micro-renewable energy. Besides, advances of technology in micro-renewable energy have also been made. There have been many demonstration projects aimed at promoting the adoption of micro-renewables. It is estimated that micro-renewables will contribute about 25% of renewable energy by 2050 (RSPB Scotland, WWF Scotland and FoE Scotland 7).
Impacts Electricity increase on the National Grid
According to The Scottish Government (c 17) the southern Scotland as well as the central belt have the capacity to accommodate new electricity generation, however, there exists some limitations in the west and the north Scottish electricity grid. The problems are related to financial, regulatory as well as technical factors. These factors inhibit connection of the decentralised generations to the electricity networks. In addition, upgrading the current distribution network is very costly (The Scottish Government (c) 17).
Increment of energy in the national grid will also require that the transmission line grid be upgraded and new routes be developed. If no upgrading is done, then the potential for the renewables are projected to reduce by 33TWh. This represents a significant proportion of the energy needs in Scotland. Thus, the identified sections of the transmission network are upgrade so as to allow accommodation of the additional consented and generated capacity. Transmission as well as distribution network models have to be developed to allow network power flow s in the existing network. According to Christiansen and Johnsen (7) whenever there are no additional capacitors that are attached to the grid, reactive power will be consumed during the normal operations leading to the reduction of energy transmitted. Voltage fluctuations may also occur on the national grid if energy is increased in the national grid. According to Edberg and Naish (64) the government plans to upgrade the existing network between Scotland and England so that it can accommodate the increasing energy flow. If this is not done within the time frames outlined, then it may lead to constraining of renewable plants. Constraints are expected to rise after 2020 if additional transmission upgrades is not done (Edberg & Naish 64).
The most Potentially Cost-effective Energy Resources
The most cost-effective energy resources in Scotland are the marine technologies and onshore wind. Marine technologies include the offshore wind, wave as well as the tidal energy resources. These renewable energy sources are widely distributed and have larger energy capacities as well as higher energy generation potential which are able to meet the projected electricity demands including surplus demands.
Onshore wind is widespread across Scotland and is also cost-effective despite the environmental as well as cultural sensitive areas that are associated with it. Onshore wind resource has a capacity of 11.5GW with potential energy production of about 45TWh which is Scotland’s estimated energy consumption in 2020 (RSPB Scotland, WWF Scotland and FoE Scotland 6-7). According to Gardner (6) onshore wind technologies are to install and this continue to be so even after 2015.
Offshore wind technologies also have huge advantages due to the greater wind strength as well as duration of wind flow found at the sea. Besides, there are no visual intrusions in the surrounding landscape (The Royal Society of Edinburgh 82). Offshore wind has a capacity of 25GW and has the potential of generating 82TWh (RSPB Scotland, WWF Scotland and FoE Scotland 7). Scotland’s capacity to generate tidal and wave energy is stimulated by the highly energetic tides and waves found around the west coast of the nation. Wave and tidal stream have capacity of 14GW and 7.5GW respectively as well as the potential to generate 45.7TWh and 33.5TWh respectively. Scotland has the relevant expertise; research as well as testing centres which can effectively drive the development and implementation of the required renewable technologies (The Royal Society of Edinburgh 82). This plus their potential energy production makes them the most cost-effective and sustainable sources for exploitation in Scotland.
Electricity Storage Technologies
Energy Storage may not be required if the proposed upgrades between Scotland and England are done within the stipulated time frames to accommodate the additional Scottish generation. If this is not done, then the Scottish generation will have to be constrained off or an additional transmission capacity could be constructed. The other option will be constructing energy storage (Edberg & Naish 64).
Proposed Energy Storage Technologies
Pumped Storage
This technology is suitable for managing fluctuations both in energy product and energy demand. The technology is capable of storing large amounts of power of about 100s of MW. It can also respond quickly to the changes in demand. The technology is least risky to the network operators as it has been widely used in Scotland (Edberg and Naish 75).
Compressed Air Storage
The technology is also capable of large scale storage of energy and also offers flexibility in functions. It can be used in the in the wind generation or in storing energy from conventional fossil plants. However, the technology is limited to areas in Scotland which have no natural caverns (Edberg and Naish 75).
Flow Batteries
The storage technology is smaller than the other technologies above; however, technology advances could help expand its battery storage. If the technology is improved, then it can provide storage solution to the grid in islands and remote areas of Scotland. It can also be used to reduce the network upgrades (Edberg and Naish 75).
Conclusion
The Scottish government’s main aim is to reduce greenhouse gas emissions through generation of renewable energy. These efforts are part of its national as well as international plans to reduce carbon dioxide emission into the atmosphere. Its future electricity generation is therefore focused in adopting technologies that will help achieve energy efficiency. With the planned closure of its coal and nuclear power plants, it focuses on adopting electricity generation that will not add more carbon emissions into the atmosphere as it fills the gaps that will be left by the abandonment of the non-renewable energy sources. The government has therefore set targets aimed at achieving its electricity demands without damaging sensitive environmental areas. The government therefore encourages the public to adopt the available micro-generation technologies and to also consider energy saving possibilities in order to achieve energy efficiency and to reduce energy demands.
Electricity generation from renewable sources in Scotland has been boosted by the large potential from the existing renewable resources. Scotland has the capacity to exploit the marine energy resources, onshore wind as well as other small energy resources like hydro energy, agricultural wastes, forestry residues, energy crops among others. Onshore wind which has energy potential of 45TWh has the capacity to meet Scotland’s estimated electricity consumption in 2020. Thus, the renewable resources are capable of efficiently meeting the country’s electricity demands plus surplus that it can supply within the UK. This makes adoption of renewable energy sources more cost-effective as the country plans to achieve 80% reduction of its carbon emission by 2050. The government has therefore identified the locations where installation of power plants for generation of electricity from the available renewable resources would be more viable and cost-effective. It has developed a policy framework to guide the economic, social as well as the environmental issues that affect the installation of renewable energy power plants. It also plans to upgrade its transmission network to give it the capacity to accommodate the additional generation that is expected to come from the renewable sources.
Given Scotland’s energy renewable resource potentiality, it is well placed to meet carbon emission as it also generates enough electricity to provide for its increasing energy demands. However, it has to care of the intermittent nature of some of its renewable resources, implying that it has to invest more on technological innovations as it locates its power plants in different areas. Upgrading its transmission network which has been limited by technical problems remains key to achieving efficiency in its electricity distribution. This will help avoid losses of energy associated with ineffective transmission networks. Installation of storage technologies to help support its transmission networks should be considered to help eliminate energy constrains which is projected to occur especially after 2020 when the electricity generation from renewable resources will have surpassed its 40% target. Upgrading of the transmission network is costly and may not be achieved within the outlined time scale; therefore, storage technologies will help provide both temporary and permanent solutions to the transmission network as they are also capable of dealing with power fluctuations.
References
Christiansen, Willi & Johnsen, David, T. Analysis of requirements in selected Grid Codes. 2006. Web.
Edberg, Oliver & Naish, Chris. Energy Storage and Management Study. Ayrshire: AEA Technology plc.
Edinburgh University. Thinking Globally: Acting with, and within, Scotland. 2008. Web.
Gardner, Paul. Options for coping with high renewable penetration in Scotland. Bristol: Gerald Hassan & Partners Ltd.
Green Investing. Scotland boosts renewable power generation. International Business Times, 2010. Web.
RSPB Scotland, WWF Scotland and FoE Scotland. The Power of Scotland: Cutting Carbon with Scotland’s Renewable Energy. Briefing Paper, 2006.
Scottish Executive (a). Going for green growth: a green jobs strategy for Scotland. Edinburgh: Scottish Executive, 2005. Print.
Scottish Executive (b). Securing a Renewable Future: Scotland’s Renewable Energy. Edinburgh: Scottish Executive. 2003. Print.
Scottish Executive Development Department. Planning for micro-renewables: Annex to PAN 45 Renewable Energy Technology. Edinburgh: Scottish Executive, 2006. Print.
The Royal Society of Edinburgh. Inquiry into Energy Issues for Scotland. Final Report, June 2006. Edinburgh: The Royal Society of Edinburgh. The Scottish Government (a). National Indicator. 2010. Web.
The Scottish Government (b). Renewable Energy: Changes to the Renewable Obligation (Scotland) Order 2010. The Scottish Government, 2010.
The Scottish Government (c). PAN 45 (revised 2002): Renewable Energy Technologies. 2005, Edinburgh: The Scottish Executive Development Department planning Services. 2011. Web.
Scottish Power Transmission Ltd. Transmission Seven Year Statement for the Years 2004/2005 to 2010/2011. Glasgow: Scottish Power Transmission Ltd. 2004. Print.
University of Edinburgh. Matching Renewable Electricity Generation with Demand. Edinburgh: Scottish Executive. Winter, John. The UK wave energy resource. Nature, Vol. 287, 1980. New York: John Wiley & Sons.