Aug 3, 2015

Part 3: The science of new and old energy – renewable energy sources

Energy Digital Staff
3 min
Renewable energy sources are largely derived from solar energy either directly or indirectly. The most promising, thus far, include solar photovoltai...

Renewable energy sources are largely derived from solar energy either directly or indirectly. The most promising, thus far, include solar photovoltaic systems, wind power and hydroelectricity; however, new technologies such as hydrogen and fuel cells show tremendous promise as well. The North American Energy Infrastructure Act brought about an integrated power grid that enables the U.S. and Canada to share energy resources. Many of the projects underway take advantage of renewable energy technologies. The Soule River Hydroelectric Project, located in Alaska, will provide hydroelectric power to British Columbia and the U.S. Pacific Northwest. Montana-Alberta Tie Limited will generate power from wind farms.

The most highly developed solar energy technologies consist primarily of solar collectors and photovoltaic systems used to convert light to DC power. Photovoltaic systems include small, thin panels of semiconductors called solar or PV cells. A chemical reaction takes place in the solar cells upon exposure to sunlight that generates electrons to produce current. The solar cells are installed on large panels, some of which are designed to track the sunlight throughout the day. Other components of the PV system include one or more batteries, a charge regulator and a inverter that converts DC current to AC current. Solar PV has become a rapidly growing industry as the cost effectiveness has improved. It offers a clean, inexhaustible source of energy. Although at present, the technology is insufficient to meet the demand for energy, many utilities, organizations and residences use solar PV systems to supplement present energy sources and help reduce costs.

As of 2013, there were 46,000 operating wind turbines in the United States. Wind energy provides 4.1 percent of the energy produced in the nation. Wind turbines are equipped with blades that are rotated as the wind blows. A shaft that connects from the blades to a generator revolves as the blades turn to produce electricity. The primary objection to the technology stems from the fact that they require a large space to generate a significant amount of power.

Canada is the largest producer of hydroelectric power in the world. Its 450 hydroelectric stations produce 62 percent of its energy. In addition, there are presently 1756 hydroelectric power facilities in the United States. Hydroelectric power facilities are typically constructed on large rivers that have a significant drop in elevation. The damn retains large volumes of water in a reservoir. Gravity forces water through an intake near the bottom of the dam wall. A turbine propeller is turned by the force of the water. A shaft connects the propeller to a generator which converts the mechanical energy to electrical power.

The various methodologies employed in energy production in North American necessitate the assimilation of a wide range of resources. At present, the vast majority of energy sources rely on a generator to convert various forms of energy into electricity. A generator produces electricity by moving wire or a disc, usually made of copper, between magnetic poles. The power distribution system requires large numbers of power cables, transformers and circuit breakers; therefore, it too demands a substantial amount of resources. Each of these systems requires maintenance and periodic replacement of parts that must be calculated into the economic viability. The North American energy infrastructure encompasses an immense range of materials and technologies and will continue to expand in the coming years.

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Jun 25, 2021

UK must stop blundering into high carbon choices warns CCC

Dominic Ellis
5 min
The UK must put an end to a year of climate contradictions and stop blundering on high carbon choices warns the Climate Change Committee

The UK Government must end a year of climate contradictions and stop blundering on high carbon choices, according to the Climate Change Committee as it released 200 policy recommendations in a progress to Parliament update.

While the rigour of the Climate Change Act helped bring COP26 to the UK, it is not enough for Ministers to point to the Glasgow summit and hope that this will carry the day with the public, the Committee warns. Leadership is required, detail on the steps the UK will take in the coming years, clarity on tax changes and public spending commitments, as well as active engagement with people and businesses across the country.

"It it is hard to discern any comprehensive strategy in the climate plans we have seen in the last 12 months. There are gaps and ambiguities. Climate resilience remains a second-order issue, if it is considered at all. We continue to blunder into high-carbon choices. Our Planning system and other fundamental structures have not been recast to meet our legal and international climate commitments," the update states. "Our message to Government is simple: act quickly – be bold and decisive."

The UK’s record to date is strong in parts, but it has fallen behind on adapting to the changing climate and not yet provided a coherent plan to reduce emissions in the critical decade ahead, according to the Committee.

  • Statutory framework for climate The UK has a strong climate framework under the Climate Change Act (2008), with legally-binding emissions targets, a process to integrate climate risks into policy, and a central role for independent evidence-based advice and monitoring. This model has inspired similarclimate legislation across the world.
  • Emissions targets The UK has adopted ambitious territorial emissions targets aligned to the Paris Agreement: the Sixth Carbon Budget requires an emissions reduction of 63% from 2019 to 2035, on the way to Net Zero by 2050. These are comprehensive targets covering all greenhouse gases and all sectors, including international aviation and shipping.
  • Emissions reduction The UK has a leading record in reducing its own emissions: down by 40% from 1990 to 2019, the largest reduction in the G20, while growing the economy (GDP increased by 78% from 1990 to 2019). The rate of reductions since 2012 (of around 20 MtCO2e annually) is comparable to that needed in the future.
  • Climate Risk and Adaptation The UK has undertaken three comprehensive assessments of the climate risks it faces, and the Government has published plans for adapting to those risks. There have been some actions in response, notably in tackling flooding and water scarcity, but overall progress in planning and delivering adaptation is not keeping up with increasing risk. The UK is less prepared for the changing climate now than it was when the previous risk assessment was published five years ago.
  • Climate finance The UK has been a strong contributor to international climate finance, having recently doubled its commitment to £11.6 billion in aggregate over 2021/22 to 2025/26. This spend is split between support for cutting emissions and support for adaptation, which is important given significant underfunding of adaptation globally. However, recent cuts to the UK’s overseas aid are undermining these commitments.

In a separate comment, it said the Prime Minister’s Ten-Point Plan was an important statement of ambition, but it has yet to be backed with firm policies. 

Baroness Brown, Chair of the Adaptation Committee said: “The UK is leading in diagnosis but lagging in policy and action. This cannot be put off further. We cannot deliver Net Zero without serious action on adaptation. We need action now, followed by a National Adaptation Programme that must be more ambitious; more comprehensive; and better focussed on implementation than its predecessors, to improve national resilience to climate change.”

Priority recommendations for 2021 include setting out capacity and usage requirements for Energy from Waste consistent with plans to improve recycling and waste prevention, and issue guidance to align local authority waste contracts and planning policy to these targets; develop (with DIT) the option of applying either border carbon tariffs or minimum standards to imports of selected embedded-emission-intense industrial and agricultural products and fuels; and implement a public engagement programme about national adaptation objectives, acceptable levels of risk, desired resilience standards, how to address inequalities, and responsibilities across society. 

Drax Group CEO Will Gardiner said the report is another reminder that if the UK is to meet its ambitious climate targets there is an urgent need to scale up bioenergy with carbon capture and storage (BECCS).

"As the world’s leading generator and supplier of sustainable bioenergy there is no better place to deliver BECCS at scale than at Drax in the UK. We are ready to invest in and deliver this world-leading green technology, which would support clean growth in the north of England, create tens of thousands of jobs and put the UK at the forefront of combatting climate change."

Drax Group is kickstarting the planning process to build a new underground pumped hydro storage power station – more than doubling the electricity generating capacity at its iconic Cruachan facility in Scotland. The 600MW power station will be located inside Ben Cruachan – Argyll’s highest mountain – and increase the site’s total capacity to 1.04GW (click here).

Lockdown measures led to a record decrease in UK emissions in 2020 of 13% from the previous year. The largest falls were in aviation (-60%), shipping (-24%) and surface transport (-18%). While some of this change could persist (e.g. business travellers accounted for 15-25% of UK air passengers before the pandemic), much is already rebounding with HGV and van travel back to pre-pandemic levels, while car use, which at one point was down by two-thirds, only 20% below pre-pandemic levels.

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