Related Links


Renewable electricity and transmission; HVDC; and supergrids

Polly Higgins

What does an electricity structure which seamlessly incorporates multiple sources of generating technology - including renewable energy - look like and crucially, how can it be achieved? Polly Higgins looks at liberalisation, long distance transmission, HVDC and supergrids.

As we attempt to encourage widespread adoption of low carbon energy sources, renewable energy practitioners are pretty much as one in saying it is vital to speed up the implementation of resource and requirement-appropriate electricity grids. Business as usual, which tips it hat in favour of the large, conventional power monopolies, is no longer an option, if renewable energy targets are to be met.

For Europe, that means some major changes ahead: the way we generate electricity, new customer requirements, and new technology opportunities. We fundamentally need to change our ageing transmission grids and electricity networks to embrace a trans-national smart grid, able to accommodate clean energy sourced from locations ranging from wind in Northern Europe, to concentrating solar power farms in the Sahara. Some of this power will be from intermittent sources (wind), some not (heat storage can be used for CSP) and power should be able to be fed back to the grid. This is contrary to the situation at present, as the flow is largely unidirectional — from the power station down to the user.

A growing consensus is gaining momentum at Brussels level: in addition to the adoption of large scale low carbon energy resources, home generated electricity from microgeneration will also become the norm, with the surplus sold to the grid. Other demands on the grid will evolve, such as the use of electric cars plugged in overnight to recharge.

Our grids will need to accommodate these varied, complex and fluctuating loads.

Supergrid of the future

Electricity networks across the EU are 40 years old (or more) and fast approaching the end of their design lives. Many national grids require substantial investment in updating, with the replacement and interconnection of networks. Rather than opting for simple replacement, now is the time for fresh thinking and innovation. We need smart grid design, with the most up to date communications' technologies to embrace the new challenges and exciting opportunities ahead.

Variable renewable energy output must inevitably be supplemented by reserve capacity, storage or increased trade with adjacent areas. Future electricity markets and networks will need to provide consumers with a highly reliable, flexible, and accessible power supply. Thus, the use of both large centralised generators and smaller distributed power sources across Europe must be fully exploited. All this and more is the vision of the future — a future that will be with us very soon.

Ten years ago the EU opened its energy markets, but until now its journey has been ponderous and largely unsuccessful, resulting in a mixed bag. Many member state energy markets are still dominated by large state-owned or private monopoly enterprises. This has prevented new suppliers from successfully entering the market, and discouraged investment. To make it work, full liberalisation of the energy market is required. We need to separate networks from supply, give new traders non-discriminatory access to the market, and facilitate cross-border energy trade.

Winds of change

But have we got what it takes to make this happen? Until now there's been a lot of talk, but little decisive action. If you look closely, however, you will notice that the winds of change have recently shifted direction. The pro-liberalisation camp has strategically advanced, and plans are afoot to make this all happen.

On 18 June 2008, the European Parliament took a decisive stance. In a move supported by the renewable energy industry and led by the Industry Committee, provisions will now be adopted in support of full ownership unbundling in the electricity market.

According to the verdict from Brussels, the separation of vertically-integrated power companies' generation assets from their transmission networks will now proceed. The high number of votes demonstrated the strength of the European Parliament's support for a properly liberalised energy market and a level playing field for renewables. Just as the telecommunications sector has been successfully liberalised, so now will the energy sector, with Brussels set to clear the obstacles that interfere with the flow of energy — and choice — across the continent.

“Allowing power generation companies to own the transmission grid makes no more sense than allowing an airline company to own the sky,” said Christian Kjaer, chief executive of the European Wind Energy Association (EWEA). “The European Parliament has shown its commitment to fair access to the electricity grids, which is essential if the EU is ever to attain effective competition in the power market while meeting its objective of 20% renewable energy by 2020.”

Transparency, accountability and accessibility. These are three buzzwords merrily bandied around by Members of Parliament in support of liberalisation of the electricity sector. There will be transparency of network rules and codes, which will apply to all grid participants, and accountability will be required of the new Agency for the Cooperation of Energy Regulators (ACER).

In practice, the director of ACER will be subject to a vote of approval by the European Parliament and will have strong decision making capabilities, not merely an advisory role. The director will be required to report back regularly to the Parliament on the agency's performance. In addition, accessibility of information will facilitate easy evaluation of consumption data while the ability to change supplier should bolster consumer protection measures.

Further measures

With climate change in mind, MEPs also authorised national authorities to require system operators “to give priority to generating installations using renewable energy sources or waste or producing combined heat and power” — except when the safety and reliability of the grid are compromised. However, some EU countries are currently attempting to have the “priority” grid access wording removed from the EU draft renewable energy directive.

In addition, national authorities are to work together to integrate their national markets “at least at one or more regional levels”, the Industry Committee decided. This would be the “first and intermediate step towards a fully liberalised common European market”. A concerted effort is also to be made towards integrating the EU's “electricity islands”.

These are all provisions with teeth.

The visionaries

For some time, many clever people from research institutes, universities, industry, regulators and utilities have been trying to determine what the future will require. With the European Parliament's move towards unbundling, the stage is set for the roll-out of a Europe-wide liberalised energy sector. This would embrace a smart grid to facilitate the flow of cross-border low carbon energy from various sources.

New alliance – Union for the Mediterranean (UMed)

But there is more: expansion of the energy sector across the Mediterranean is now less than a decade away. On 13 July 2008, with the arrival of the EU French presidency, a Mediterranean Union was formally endorsed, promoting regional co-operation between the EU and developing nations in North Africa bordering the Mediterranean. Touted as a multilateral relationship, this union will build on the existing Euro-Med free trade area, increase co-ownership of the process and making it more visible to citizens.

Named the “Barcelona Process: Union for the Mediterranean (UMed)”, it encompasses all 27 EU Member States and the European Commission, together with other members and observers of the Barcelona Process (Mauritania, Morocco, Algeria, Tunisia, Egypt, Jordan, Palestinian Authority, Israel, Lebanon, Syria, Turkey and Albania), as well as other Mediterranean coastal states (Croatia, Bosnia and Herzegovina and Monaco).

UMed has opened the door to the flow of energy supplies between the countries bordering onto the Mediterranean basin and Europe. It is anticipated that grid interconnections will be in place between Member States of the EU before 2020, facilitating connection of low carbon energy sources across the Mediterranean basin, from North Africa and further afield.

An old idea

The idea is not new. In the 1970s, Buckminster Fuller envisioned an interconnected global grid linked to renewable resources.

For the past 22 years the Global Energy Network Institute (GENI) has investigated his proposal for a global electric energy grid. GENI has conducted research on the viability of the interconnection of electric power networks between nations and continents, with an emphasis on tapping abundant renewable energy resources. Its research serves to underline the potential benefits: ideally, linking renewables among all nations will dampen down conflicts, grow economies and increase the quality of life and health for all.

Like Copernicus, Buckminster Fuller was ridiculed by some for his expansive vision. However, technological development now moves power further and more cheaply than 30 years ago, just as he envisioned it would. For example, when Fuller first put forth his vision, electric power could only be efficiently transmitted a few hundred kilometres.

Since then, breakthroughs in materials science have extended this transmission distance to 2500 kilometres, and Direct Current (DC) lines are now able to reach over 7000 km. This allows utilities to interconnect across time zones and compensate for variations in seasonal demand.

Today about 2% of all electricity is transmitted along HVDC lines, in more than 90 projects around the world, linking large energy projects to centres of high energy demand.

Most networks are historically predicated on Alternating Current systems (AC), which were chosen over 100 years ago because it was easier then to transform AC supply than DC supply. Now, with the development of high-voltage valves, it has become possible to transmit DC power at higher voltages and over longer distances with lower transmission losses.

Research by the International Energy Agency, as set out in its recent report, Energy Technology Perspectives 2008 — Scenarios and Strategies to 2050, supports the use of DC transmission systems. With losses typically around 3% per 1000 km, it makes economic sense for long-distance and sub-sea transportation. In the case of wind electricity, the IEA estimates that transportation over 2000 km would add US$0.02-US$0.03 per kWh. To connect across the Mediterranean basin would require only 400 km – 600 km, depending on where the links were positioned. In theory, an HVDC line could be laid from Morocco to London, a distance of 2700 km, with losses of less than 8%.

New impetus

Even in early 2008, interconnection between Europe and other continents was deemed an audacious idea — except by TREC UK (Trans Mediterranean Renewable Energy Co-operation).

For the past five years, TREC, an initiative of the Club of Rome, has promoted the DESERTEC concept of building Concentrating Solar Power (CSP) plants out in the Sahara desert — to provide clean renewable electricity. Now TREC has successfully advanced the concept of a renewable energy transmission network combining CSP with wind farms and other renewables to transmit power to Europe from the Middle East and North Africa, via high voltage direct current (HVDC) cables across the Mediterranean.

The newly formed UMed, which has been backed by, among others, France, Germany and the UK, is now prepared to take such thinking forward.

UMed is planning the construction of a €45 billion high voltage direct current (DC) grid to transfer electricity produced by Saharan and North African solar installations to consumers thousands of kilometres away. The Project Proposal is called the Mediterranean Solar Plan (Med Solar).

Med Solar Plan

Key objectives of the Med Solar Plan are to expand the integration of energy markets and promote sustainable development through the creation and development of a solar market.

It is proposed that key skills will be shared, and market players from the EU will help facilitate such a development, with the long-term aim of importing solar electricity into the EU.

The Med Solar Plan is expected to ensure a multilateral mobilisation of the relevant political authorities, institutions and financial sectors. Recognising that energy policy in developing nations is still piecemeal at best, it proposes that the European Commission will promote the framework for the necessary dialogue on the energy policies and sectoral strategies that must be implemented by the various countries. It will build on the established work of existing initiatives such as the Euro-Mediterranean Energy Market Integration Project. This will include the building of HVDC grid connections across the Mediterranean basin.

The Med Solar Plan aims to have in place 20,000 MW of CSP in North Africa by 2020. Estela Solar, the European Solar Thermal Electricity Association, estimates that a further 36,000 MW of CSP will be online in Southern Europe by 2020.

If the projected annual growth rate of CSP through 2012 is maintained to 2020, says the Earth Policy Institute, global installed CSP capacity will exceed 200,000 MW — equivalent to 135 coal-fired power plants. With billions of dollars beginning to flow into the CSP industry, and restrictions on carbon emissions imminent, CSP is primed to reach such capacity.

Encouragingly, the Med Solar Plan has even been backed by UK Prime Minister Gordon Brown. Speaking recently at the inaugural meeting of UMed in Paris, he said “…in the Mediterranean region, concentrated solar power offers the prospect of an abundant low carbon energy source. Indeed, just as Britain's North Sea could be the Gulf of the future for offshore wind, so those sunnier countries represented here could become a vital source of future global energy by harnessing the power of the sun. So I am delighted that the EU is committing at this summit to work with its neighbours — including Egypt, Jordan, Morocco and the League of Arab States — to explore the development of a new ‘Mediterranean Solar Plan’ for the development and deployment of this vital technology from the Sahara northwards”.

Wind supergrid

Compare this with wind: If the present 27% annual growth rate of installed wind power capacity is maintained (100,000 MW having been reached in March of 2008), total capacity in 2020 will hit 2,000,000 MW.

With their enormous growth potential, wind and solar will be foundation players in our long-term future low carbon energy economy. A supergrid would treat wind and solar (and other renewables) as trans-national resources, which would enable all participants to share in the enormous energy potential, to everyone's advantage.

TREC has not been the only body to call for the connection of renewable energy systems with a supergrid. Airtricity has also presented proposals to link in their offshore wind farms throughout Europe via a high voltage sub sea transmission network. They say it could ultimately cover the Baltic Sea, North Sea, Irish Sea, the English Channel, the Bay of Biscay and the Mediterranean. With such a geographically extensive range, fluctuating availability becomes less of an issue. By building windfarms in the seas around Northern and Western Europe, as well as areas of the Mediterranean, it would become possible to harness the wind whenever it is blowing and transform it into a stable source of power, Airtricity claims.

Other high-profile supporters include the EU's energy commissioner himself, Andris Piebalgs, who has said a maritime grid infrastructure must be developed quickly for the development of offshore wind energy. Speaking at the European Wind Energy Conference in 2008, the commissioner said without the infrastructure no offshore wind farms can be built: “As it is not yet in place, it must be developed fairly quickly and a central question is how it should be financed”.

According to Piebalgs, the European Commission is looking to adopt an offshore wind action plan by the end of this year. He said that although member states have taken steps forward to collaborate on offshore development, there is scope for increased cooperation, and he maintained that the EU could play an important role in facilitating further joint efforts.

The commissioner said the creation of the pan-European sub-sea energy grid, SUPERGRID, should help the incorporation of large quantities of offshore wind into the European electricity market.

Practical realities: first steps

On the legislative front, it can be said that the necessary frameworks for a low carbon renewable energy future are now starting to shape up.

For example under the European Commission's Seventh Framework Programme, the European Commission has ring fenced €2.3 billion to fund a number of projects in smart energy networks.

And collaborations such as that between the New and Renewable Energy Centre (NaREC) in the UK and CENER, National Renewable Energy Centre of Spain — which are working together to find new ways of generating and distributing power from small-scale renewables within communities — will certainly help focus attention on supply, and remove the perception that technological challenges are insurmountable (the one year project will investigate ways to allow communities to generate and use their own power from renewable energy resources, in a reliable and cost-effective way).

But it is still early days; the EU Renewable Energy Directive is still being debated and may yet provide some surprises (note the UK's recent — but so far unsuccessful — attempts to exclude the mandatory requirement to implement priority access to the grid for microgeneration). The European Commission estimates that EU Member States will need to invest in excess of €750 billion in power infrastructure over the next three decades, divided equally between generation and networks (some €90 billion will be invested in transmission and €300 billion in distribution networks). The EU has yet to commit any major funds towards such a massive upgrade or transformation of the Bloc's energy infrastructure. In addition, the EU has yet to secure funding for a range of “low carbon” technologies. That's not to say it can't or won't happen — it will. The question is: can we do it fast enough?

About the author
Polly Higgins is a barrister and works for TREC UK. She can be contacted at


Share this article

More services


This article is featured in:
Energy infrastructure  •  World Future Energy Summit