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Renewables growing fast, but not fast enough

10 Jul 2018 Dave Elliott
Photo of row of pylons in the English countryside. Courtesy: iStock/John Kelly
Courtesy: iStock/John Kelly

The headline figure in REN21’s 2018 review of the global status of renewable energy is that, in 2017, renewables supplied 26.5% of global electricity, which coincidentally was about the same as for the UK. The UK has now moved up to around 30% and that may well be true globally too. Certainly, REN 21 says that renewables’ share of final energy consumption has continued to grow globally, at around 5.4% averaged over the last 10 years for modern renewables, more for some technologies. By contrast, over that period, fossil and nuclear only grew by 1.6% and energy demand by 1.7%.

REN 21 reports that 178 GW of renewable power generation capacity was added in 2017. That was 70% of net additions to global power generating capacity in 2017, the largest percentage so far, bringing the global total to 2195 GW, with non-hydro renewable capacity (in all 1081 GW) likely to overtake hydro capacity (1114 GW) in 2018. Of the new capacity added in 2017, 159 GW was non-hydro renewables and 19 GW hydro. Overall, with hydro included, renewables accounted for 26.5% of total global electricity generation in 2017, up from 24.5% a year earlier, with hydro at 16.4%, wind 5.6%, bio-power 2.2%, solar PV 1.9%, and 0.4% for ocean power, concentrated solar, and geothermal combined.

 In 2017, 52 GW of wind capacity was added, bringing the global total to 539 GW. But that was lower growth than in the previous year, due mainly to a slowdown in China, in part a result of problems with curtailment – about 42 TWh of wind energy was curtailed in China last year. Even so, at 19.7 GW, China was still the leader in new installations. Of the total global installed wind power, 18.8 GW was offshore, with nine countries adding 4.3 GW in 2017, led by the UK (1.7 GW), Germany (1.2 GW) and China (1.2 GW).

Solar photovoltaics (PV) have continued to expand rapidly, installing more capacity than any other power generating technology, and rising by 98 GW, about 33%, in 2017. That has increased the global total to about 402 MW. China led, with PV installations growing more than 50%.

However, while progress was good for electricity, REN 21 says “the power sector on its own will not deliver the emissions reductions demanded by the Paris climate agreement…to ensure access to affordable, reliable, sustainable and modern energy for all. The heating and cooling and transport sectors, which together account for about 80% of global total final energy demand, are lagging behind”.

That point is reinforced by REN21’s new adjusted figures for the total global renewable energy contribution, including biomass, which has only grown by 2.3% over the last decade, mainly since the use of traditional biomass, e.g. in China, has fallen, cutting global biomass’ growth rate to 0.2%. The result of that, and other changes, is that the estimated total global renewables share of final energy consumption was only around 18.2% in 2016, down from the 19.3% estimate in the 2017 REN21 review, with modern renewables now at 10.4%.

Seeking to improve that, REN21 looks at system integration, and better end-use efficiency, e.g. in heating and transport. Rana Adib, executive secretary of REN21 said: “We may be racing down the pathway towards a 100% renewable electricity future, but when it comes to heating, cooling and transport, we are coasting along as if we had all the time in the world. Sadly, we don’t.” REN21 said of particular concern was that global energy demand and energy-related carbon dioxide emissions rose for the first time in four years in 2017, by 2.1% and 1.4% respectively.

The International Energy Association’s Tracking Clean Energy Progress review came up with a similar message, but reflecting the IEA’s wider set of technology commitments, including nuclear and fossil carbon capture and storage (CCS). While there was some good progress, energy efficiency improvements had slowed and progress on CCS had stalled. Progress in deploying onshore wind and energy storage had also slowed. Nuclear was also unlikely to meet the level envisaged in the IEA’s 2025 Sustainable Development Scenario. Overall, Fatih Birol, IEA head, said: “there is a critical need for more vigorous action by governments, industry, and other stakeholders to drive advances in energy technologies that reduce greenhouse gas emissions. The world doesn’t have an energy problem but an emissions problem, and this is where we should focus our efforts”.

However, there have also been some more positive reports, mapping out a different, more optimistic view, with energy efficiency seen as key. Indeed, in its Energy Transition Outlook, the DNV-GL global consultancy company claims that efficiency will dominate so demand will fall. It says the energy intensity of the global economy, i.e. the energy used per unit of economic output, will improve more quickly than the rate of global economic growth in the next three decades. As a result, global energy demand will flatten for the first time in our post-industrial history.

This view is also central to a new academic study. Published in Nature Energy, the study claims that it is possible to reduce global energy demand so that by 2050 it falls to 245 EJ, around 40% lower than today, despite rises in population, income and economic activity. Using an “integrated assessment modelling” framework, it shows how changes in the quantity and type of energy services, affecting demand patterns, drive structural change in intermediate and upstream supply sectors. Overall it says that “down-sizing the global energy system dramatically improves the feasibility of a low-carbon supply-side transformation”. Its Low Energy Demand (LED) scenario meets the Paris 1.5 °C climate target as well as many sustainable development goals, without relying on negative emission techs.

One of the keys is seen to be smart digital IT-based energy systems. “The integration of multiple service functions in single devices (particularly smartphones) yields up to a 100-fold potential power saving while in use. Devices increasingly become ‘smart’ & interconnected, which opens up potential for controllability, system integration (including load management) and demand response.” That also helps with mobility services and transport while, overall, “energy intensity improves drastically due to the combined effects of electric vehicles and new organizational models of service provision, which include shared mobility”.

Energy and resource-use efficiency is upgraded in all sectors, cutting demand: “Industrial-process energy efficiency improves by one-fifth. The aggregate total material output decreases by close to 20% from today, one-third due to dematerialization, and two-thirds due to improvements in material efficiency. ‘Dematerialization’ describes a lower absolute material use due to increases in asset utilization, for example, shared-car fleets that require fewer cars. ‘Material efficiency’ includes light-weighting, for example, less material input per car”.

Changes in energy end-use drive a supply-side transformation, with “strong electrification of energy end-use, consistent with the narrative of pervasive digitalization and more versatile end-use technologies that are also non-polluting at the point of use. Over the longer term, hydrogen also increases its share of the final energy demand (in addition to its role for energy storage)”. Consistent with the LED scenario narrative, “granular energy-supply technologies, such as heat pumps, fuel cells and solar photovoltaics proliferate. Granularity, decentralization and variable renewables pose significant challenges for system management and balancing, addressed via ‘smart’ transformation of physical networks and control systems and scaled-up storage and load-management options”.

The study team admits that a massive effort would have to be made to bring all this to reality: there would have to be “rapid innovation, cost reductions and performance improvements from the widespread diffusion of granular end-use and low-carbon supply technologies”, that would require “sustained innovation policies aligned to credible efforts to stimulate market demand”, while regulators “need to ensure that space is opened up for new business models, digital integration and distributed service provision to overcome incumbents’ vested interests to slow structural change”. But it claims it is technically viable. If so, that’s a huge game changer, allowing renewables to deliver all that’s needed, and cutting emissions fast. Too good to be true? It certainly looks impressive, if a little fantastic. A vast series of technical fixes. See Carbon Brief’s review of the paper.

 But for very different views, see some of the oil company scenarios in my next post.

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