Renewable energy and the building and construction sector impact each other in several ways. The industry is both a consumer that is being urged to cut its carbon footprint and a provider of the new green power generating infrastructure where technical developments are racing ahead. Jon Herbert reports.

As substantial energy users, building and construction companies are being urged to increase energy efficiency, minimise supply chains carbon for financial as well as environmental reasons and, with the UK’s poor air quality record in mind, actively reduce emissions from site vehicles.

However, many firms are also part of a renewable energy infrastructure supply chain. A snapshot of that sector’s current size can be seen in April’s update of the Renewable Energy Planning Data (REPD) database. This provides a comprehensive overview of more than 6000 renewable electricity projects revised monthly as they move through the planning system.

The Department for Business, Energy and Industrial Strategy (BEIS) uses REPD, which plots projects of 1MW or more, to forecast renewable development trends and keep the UK on course for a target of 15% of total energy from renewables by 2020. However, it also helps industry to track development opportunities.

Fair competition

The Government is also supporting the development smart energy systems for homes and industries as a subset of the wider renewables revolution. In May 2018, through Innovate UK, it invited applications from companies and organisations to share circa £41.5 million earmarked for practical smart energy system demonstrations with export potential. The deadline is 25 July.

As part of the Industrial Strategy Challenge Fund programme, the goal is an intelligent link-up of supply, storage and demand in heating, power and transport. Of the total, £40 million will fund three smart energy system demonstrators, with £1.5 million going to studies into smarter approaches to local energy.

Successful projects will be further supported by leading researchers, Government and independent regulatory bodies through the Energy Systems Catapult. By the early 2020s, smarter local energy systems should be delivering cleaner and cheaper energy services to medium-sized towns.

Construction involvement

The construction sector has a key role in the development of UK renewable energy hardware and expertise as a domestic resource with significant export potential. One major challenge and infrastructure opportunity is to take large amounts of increasingly cheap, low-carbon energy generated on windy days and/or sunny days and use it cost-efficiently on dull calm days.

It is estimated the UK could also host 50% of Europe’s tidal energy resources, both as subsea turbines in tidal channels and tidal lagoons, if and when that technology is perfected. In addition, innovator Kepler Energy is developing a horizontal axial second-generation tidal turbine system that could extend over many kilometres as an energy “fence” through shallow waters such as the Bristol Channel.

With changing distribution networks designed to average out intermittency problems in renewable generation over wide geographic areas, plus smart grids that allow domestic and small business microturbines and solar panels to sell power back to the grid while synchronising domestic appliances with periods of low power demand, energy storage on many different scales is on track to be big, with construction opportunities.

Time to change the batteries

Until quite recently, one vital element is still missing. To remedy this, the Government is investing £246 million in a “battery institute”: industrial-scale battery development. Lithium-ion battery costs fell swiftly from 2010 to 2015 — when the Tesla Energy 10kWh home battery was introduced — and have flatlined at a very low level since.

In December 2014, what was then Europe’s largest electricity storage facility of its type went live at Woodman Close substation in Leighton Buzzard, Bedfordshire, for a two-year trial. The 6MW/10MWh battery is the size of three tennis courts and can store enough energy to power some 6000 homes for 1.5 hours at peak times. But R&D moves on.

The world’s largest battery at this point has been Tesla’s 100MW Big Battery in South Australia built by Elon Musk last December. In May, it was reported that Big Battery, which stores excess energy from the neighbouring Hornsdale Wind Farm, had saved local people millions of dollars in backup power costs, reducing the price of expensive power outages by 90%. However, it may be overtaken by a Palm Springs’ proposal for a 350MW solar farm back up by Recurrent Energy owned by Canadian Solar.

Becoming mainstream

An All-Party Parliamentary Group on energy storage predicts the UK could have a 12MW battery market by 2021. In practice, 8GW from 60MW of capacity is more likely. In April, National Grid also issued co-location storage and power station advice welcomed by the Renewable Energy Association.

Low carbon content

Low carbon thermally efficient materials are also important in reducing the environmental impacts of new and retrofitted buildings. It is good practice to minimise embodied carbon that sneaks into the supply chain, make procurement and processes sustainable and use local suppliers who understand the principles involved. Designing energy-efficient buildings with low energy heating and lighting and installing onsite renewables is also good practice.

The triple-hierarchy approach is to:

• cut energy use
• raise energy efficiency
• use renewable energy.

Solar panels, but also low maintenance systems such as ground source heat pumps, are often chosen. BREEAM and Passivhaus standards are designed to support these aims.

Air quality implications

Energy storage has a health and safety benefit, too. It was announced on 17 May that the UK is being taken to court by the European Commission over long-standing failures to meet EU nitrogen dioxide (NO₂) limits caused largely by diesel engines. The Government has promised a comprehensive air pollution package shortly having already lost a series of air pollution battles in the UK courts.

European Environment Commissioner, Karmenu Vella, warned, “We can’t possibly wait any longer. It’s high time to intensify efforts and end exceedances (of pollution levels)”. A move towards electric vehicles (EVs) and battery storage technology is suggested as part of the answer. However, before that, a major drive continues to reduce diesel pollution dramatically from building and construction sites.

An air quality report for the London Atmospheric Emissions Inventory found recently that around 7.5% of damaging nitrogen oxide (NO_x) comes from construction sites, which are also responsible for some 8% of large particle emissions, plus about 14.5% of the most dangerous fine particles (PM_2.5). The source is thousands of diesel-powered earthmovers, generators and ancillary equipment that are not subject to the emission standards that apply to on-road vehicles.

Last year, Mayor of London, Sadiq Khan, announced plans to fine firms using polluting equipment in the same way that congestion charges are imposed; rules on emissions from central London building sites are also being strengthened.

Implications

In creating the built environment, building and construction companies are consumers of sustainable green energy. They also have responsibilities to use low-carbon materials and processes that reinforce the aim of switching over from high carbon fossil fuels to renewable energy sources.

A key change at present is the rapid emergence of effective battery storage technologies of all sizes that make it possible to keep low-cost wind, solar, tidal, hydro and other renewable energies generated today for use tomorrow when the wind drops, and grey clouds fill the skies.

An increasing number of industrial scale battery storage facilities are being seen around the UK, a trend that is expected to continue.

Published by Croneri on 25 May 2018