Renewables are pointing the way towards Electricity 2.0

For at least 15 years, wind and solar have been changing our power systems irrevocably.

This piece was published as part of the Thought Leaders series. Recharge’s Thought Leaders Club brings together leading thinkers and participants from the renewable-energy sector to examine the key challenges facing our industry

By Alfredo Parres, March 2015

Initially, there was a belief that renewables were simply an extension of the existing energy mix that we could integrate seamlessly without fundamental changes. Nothing could be further from the truth.

Renewables have become one of the largest subsectors of power generation in many countries, with further, accelerated growth expected as the costs of these technologies fall. As a result, we are experiencing substantial challenges in maintaining the stability and reliability of grids. It is becoming clear that the main task is not simply to connect wind farms into existing systems, but to develop new, effective systems capable of incorporating ever-larger amounts of renewable energy.

In most of the developed world, transmission and distribution grids were built to serve large, centralised generation plants based on fossil fuels or nuclear energy. And it is a job they have performed very well. Furthermore, these plants are usually relatively close to the population and industrial centres that consume the power.

That is changing, because wind energy is strongly linked to location; turbines need to be installed where the wind blows — in remote countryside or far out to sea — which means production is often distant from the point of consumption. In many cases, we are aiming to feed large amounts of energy into the grid at its extreme fringes, a function it was never designed to handle, and where it may lack the required strength and capacity.

There is also major growth in distributed generation, mainly solar, and combined heat and power, so distribution grids need the flexibility and smart capability to handle large numbers of small embedded generation units.

The volatility and rapid ramp rates of wind and solar also lead to faster, larger, relatively unpredictable supply-side fluctuations in grids that were designed to handle predictable baseload generation, supported by peak-load plant.

These challenges have technical implications in all aspects of the supply and use of electricity. Three developments are particularly noteworthy: the growing importance of long-range, high-performance transmission networks; the development of smart power-management systems; and the integration of highly distributed elements, both in production and the smart management of consumption.

Large-scale renewable generation, especially offshore wind, is driving the development of long-distance networks, especially those based on high-voltage direct-current (HVDC) technology.

These networks have a key role to play in bringing wind energy produced far out to sea and integrating it into the onshore grid. They also enable the creation of interconnectors that allow the two-way transfer of energy between countries and regions, providing an effective method of compensating for the production peaks and troughs of different primary energy sources. An excellent example is the 1.7GW Skagerrak transmission system, comprising several HVDC links, which helps balance the loads between Norway’s hydro-based system and Denmark’s wind- and thermal-based generation.

HVDC converters can also play an important part in maintaining grid stability by providing vital support for grid frequency and voltage.

The next steps will be the creation of long-distance, international, meshed, multi-terminal high-voltage grids that may even include offshore elements. With the introduction of our DC circuit-breaker in 2012, ABB removed the last main technical hurdle to achieving this with HVDC technology.

In terms of smart power management, wind and other renewables can have a vital role in supporting system stability and reliability. They can also participate in ancillary markets through intraday markets and virtual power plants. The technology is already available, including the capability to integrate wind turbine controls with smart control systems and forecasting. For this to become reality, we need the energy-market reforms being prepared in Europe and expected in China.

Of all the changes ahead, the continuing shift to highly distributed, variable generation will probably have the most far-reaching effects. Since a lot of the new generating capacity is being connected at the distribution level, there are much greater demands on system management.

Furthermore, in the case of solar, the pronounced in-feed peaks call for congestion management. This demands a new kind of distribution grid. One that enables control protection schemes and new technology such as energy storage to ensure safety, continuity and quality of supply. One that offers a seamless integration of operational technology with information technology. And one that enables grid operators to deal with local issues, while taking the bigger picture into account.

The growth of renewables demands a fundamental reassessment of the way we approach the design and construction of grids, challenging principles of electrical transmission and distribution that have stood unchanged since alternating-current networks were first developed in the late 19th century. Get ready for Electricity 2.0. 

Alfredo Parres is head of ABB’s Wind Industry Sector Initiative. Based in Beijing, he is chairman of the Renewable Energy Working Group at the EU Chamber of Commerce in China. He is also a board member of the European Wind Energy Association and chair of its networks working group

  • Contact us

    Submit your inquiry and we will contact you

    Contact us
Select region / language