Renewable EV charging: the future of electric mobility?

renewable ev charging
© iStock/Solovyova

Geoff Nesbitt, CEO of clean technology provider Verditek PLC, discusses the sustainability potential of renewable EV charging capability.

Electric vehicles (EVs) are going to define future transportation needs. To address their charging requirements, we have an opportunity to rethink the petrol station paradigm. Solar power, in the form of photovoltaics (PVs), offers an opportunity to implement renewable EV charging sustainably and with a low carbon footprint. The requirement will be large and persistent; and is likely to require a mix of solutions to be effective. PPAs, microgrids, lightweight PV panels and novel battery technology all have a role to play and help provide a comprehensive solution.

The world has come a long way in reducing transport burden in the last decade. Depending upon where you live and work, you may have access to flex-office, flex-hours, public transport, park and ride, company busing; all of which help reduce your impact on the planet. But there remains a fundamental need to transport people and goods to where they are needed and governments honouring climate targets are working to phase out vehicles powered by fossil fuels.

Charging stations will be required to meet growing demand; to ease user anxiety, an ideal system will strive to provide a charging opportunity whenever the EV is parked. Several scenarios can provide solutions to this challenge, the question being which can best optimise commercial viability, technical reliability and system sustainability?

At the top of the list, two strategic possibilities could address the additional power requirements EVs will place on the National Grid: either expanding the existing utility infrastructure most countries currently have in place; or encouraging the development of a distributed independent network. Or will a hybrid system be most robust?

The role of government in the UK

Following the UK government’s commitment to phase out the sale of new combustion engines by 2040, energy regulator Ofgem has outlined proposals that will help the existing grid cope.

Millions of electric vehicles are forecast to join the UK’s roads in the decades ahead and the Ofgem proposals also aim to keep energy costs down for those vehicle owners. The proposals also intend to safeguard all energy consumers from potential rises in energy costs as a result of the rise in demand.

Under the proposals, owners would be encouraged and incentivised to follow a flexible charging programme, charging their vehicles outside of the peak hours where the grid sees most demand. Ofgem reports that at least 60% could be accommodated through flexible charging if owners chose to charge their vehicles during the peak hours of grid system demand. During these out of peak hours, energy prices are cheaper, but to accommodate the influx of electric vehicles clean energy can be generated to satisfy higher demand during those cheaper charging periods.

Rural and urban solutions

Infrastructure planning recognises a large difference in approach required for city and rural infrastructure solutions.

In a city, the high density of activity and buildings brings persistent need for materials and people. Supply and demand profiles are largely predictable and can be severe as people and business culture normalises daily activity profiles. In cities property prices are generally high, prompting greater efforts towards the efficient use of space; while air quality is always a challenge and noise is chronic. The density of well-paid users can be a commercial advantage, inviting competition and lower average user costs.

In a rural environment a lower density of people and buildings leads to relatively infrequent user demand, with longer distances to travel and to connect infrastructure. The growth of satellite suburban towns within commuting distance of large cities provides high enough concentration of users to average out infrastructure costs, striking a balance with quality and cost of living; but at the expense of travel to work. Train, tram and bus systems can help, but the first and last mile from home to depot or depot to work can present significant obstacles.

What are the barriers to renewable EV charging?

While conventional solar PV panel costs have continued to decrease over the last decade, that descent has slowed as supply chain economics reach their limits of efficiency and consolidation of manufacturers has shifted to countries with the lowest labour costs. Most government subsidy programs have been discontinued and the market is now determined by owners’ calculated rate of investment in the face of continuing rise of grid utility supply costs.

The main issues for any residential or commercial party considering installing an array of solar panels are space, shading and weight. Conventional silicon solar panel efficiencies typically range from 15% to 21% depending upon the quality of materials used, which is reflected in the cost per watt. Typical power yields range from 150 to 200 watts per square metre, with a typical house in moderate climate requiring 8kWh to 10kWh per day. Houses in extreme cold or hot climates can require double that power due to heating or cooling demand.

For most businesses and residential neighbourhoods, space is at a premium. If a structure has substantial roof area accessible, with a good orientation to available sunlight and no shading, then conventional panel modules could be a solution. In many cases the rooftop surface is small or inaccessible or cannot tolerate the weight of a conventional panel and framing system. In this case lightweight panels can offer a solution either substituting for conventional panels at less than a fifth of the weight or allowing cost effective carports and canopies to be created above parking spaces or recreational areas.

Verditek is working with partners to create carpark and canopy solutions which can be used to power renewable EV charging points or directly to offset peak power requirements. Verditek Solar Italy manufactures a lightweight PV module using high quality mono-silicon wafers laminated between robust polymer layers so that no heavy glass sheet or aluminium frame is required.

Partnering with Engenera, a premier UK EPC company specialising in renewable energy solutions for its clients, Verditek offers a tailored solution that helps remove the threat of volatile utility prices and provides project owners and businesses with predictable savings.

Engenera has developed a four-step process to help businesses reduce energy bills and their carbon footprint, removing up-front costs and maintenance burden as barriers to a sustainable future.

ESCO impact

The success of energy service companies (ESCO) in improving efficient management of energy profiles for commercial and government organisations has been demonstrated, most notably in the US and EU. Typically, an ESCO would offer the following services:

  • Assisting a user to define their sustainability and energy savings goals to become more efficient. This would include securing internal agreement and buy-in from the work floor and leadership and result in a proposal to improve energy performance;
  • Increasing awareness in the organisation of various methods of achieving savings and increasing energy efficiency. Resources are available online;
  • Performing basic energy audits or benchmarking exercises to understand consumption patterns;
  • Hire a quality service provider to support or deliver energy efficiency services based on the needs of the business, taking into consideration risk, investment and targets; and
  • Monitoring and reporting on progress, while implementing an evergreen improvement programme.

Optimeyes is a project developer providing clients with integrated solutions in renewable energy generation projects in the EU and the UK. They have developed a full range of services comprising energy compliance audits, optimisation analysis for businesses, energy efficiency programs to reduce utility spending; and has a track record in creating financial instruments to ease client entry into capital purchases that reduce the long term burden of utility costs.

Case study of a solar carport power purchase agreement

The shift towards renewable energy is an opportunity for businesses and organisations to invest in realising their own renewable power generation technologies. By creating their own microgrids, businesses and organisations will not only generate significant energy savings while reducing their own carbon footprints: they can also contribute additional energy to the grid, supporting the nationwide effort to curb climate change by generating clean, cheap energy to power emission-free vehicles.

Most commercial businesses provide car parking facilities for their employees and guests. In most cases this is unsheltered space and offers an abundance of surface area to harvest sunshine. By creating a lightweight renewable EV charging structure to secure a lightweight panel system, it is possible to realise more than enough power to charge EVs and the potential to sell excess electricity back to a grateful utility company. The modest structure required allows architects and engineers room to become creative and increase visibility and safety for vehicles and pedestrians.

Depending upon the commercial structure that best benefits the client, investment finance providers have become interested in funding the system. The client has the advantage of a predictable electricity bill for 10 to 20 years to come, at a discount compared to current utility costs; while the investor receives low risk returns at attractive rates.

Microgrids

Many nations are implementing changes to their national grid infrastructure to respond to the adoption of renewable power sources. Several decades of investment in centralised utility grids, based on maximising the economy of scale, has resulted in large grid systems connecting remote users to large power stations which are run at full capacity to extract the maximum output from the invested capital. This principal can be effective, despite the capital investment and transmission costs incurred in moving electricity or gas over long distances. Economic studies over the last two to three years indicate that with falling prices of solar, wind and heat pumps, the total cost of ownership is now significantly cheaper for renewable energy than compared with natural gas, the next best conventional energy source. The issue that emerges is that the total grid system performance decreases when adding significant renewable (intermittent) energy sources to a utility system designed for constant, large, baseload power stations. Although the grid itself can be used as a storage facility, balancing the demand against the supply profile over a large grid and variable weather is extremely challenging.

Ultimately a significant investment in large scale storage, such as pumped hydropower, is required to smooth out fluctuations. Another consequence is that legacy baseload plants, which must address demand if solar, wind or other sources are not supplying energy, will need to operate at low capacities where possible when the sun is shining or wind blowing; which undermines the capex and opex efficiency of the entire system.

However, there is a solution that can extract the best out of the renewable energy injection into our supply side, while minimising disruption of established baseload grid systems. It requires applying strategies that have been proven in manufacturing, engineering and computer systems to microgrids. In simple terms, a microgrid can be used to manage the complexity of a local community’s energy needs which, when connected to the larger grid, reduces the number of transactions (supply and demand events) that must be managed by the Grid, and simplifies forecasting.

Microgrids also localise investment, making the project developer or end user community actively involved in the generation and utilisation of energy. This ownership and awareness by the user community in the microgrid promotes efficiency at source with responsible management rewarded in lower bills.

Conclusion

There have been calls for governments to bring the ban on petrol vehicles forward to 2030. Current national infrastructures cannot cope with the shift of fungible power from liquid fuels to electricity without major investments in renewable EV charging facilities. This will be financially crippling to any central government, but by encouraging investment in new technologies and new financial instruments the economy can benefit from the transition, as the world moves to a sustainable future.

Geoff Nesbitt

Verditek PLC

+44 (0)207 129 1110

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