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Momentum is increasing towards a flexible electricity system based on renewables


Total global energy use is rising, and remains based on fossil fuels. Yet, the challenge of climate change requires a deep decarbonization of our energy system. Here I argue that the global energy policy discourse is moving rapidly towards one of renewable, energy-efficient and flexible electricity systems. This is primarily because of a rapid take-up within a few countries of variable renewable electricity sources over the past decade, resulting from falling renewable electricity prices, new and more economic means of flexible system operation, and changing social preferences. This in turn has led to widespread and supportive public policy announcements. I also argue that a ‘no-regrets’ energy policy is one that increases the energy system flexibility. Although the changing discourse is welcome, it is not to say that the challenge of climate change has been met. Policy statements must be backed up by more effective governance support and pressure to speed up change.

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Figure 1: Global primary energy demand by fuel type.
Figure 2: Cost and deployment of rooftop PV systems in Germany over 1990–2014.
Figure 3: Additional capacity trajectories of renewables versus other power sources over 2001–2013.
Figure 4: Minutes lost per customer in Germany relative to installed renewables capacity over 2006–2014.
Figure 5: IEA solar technology roadmap high-renewable scenario projections for 2050 as a share of global electricity supply.


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C.M. acknowledges support as an EPSRC Established Career Fellow, EPSRC grant reference EP/K001582/1.

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Correspondence to Catherine Mitchell.

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Mitchell, C. Momentum is increasing towards a flexible electricity system based on renewables. Nat Energy 1, 15030 (2016).

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