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Greater acceleration of renewables required to meet COP21 goal

Gail Rajgor

Solar PV and wind power will be the keys to meeting carbon emission goals set at COP21 last year, but there needs to be a significant increase in deployment rates of all low carbon technologies for the goals to be met, says the International Energy Agency in a recent report. Gail Rajgor reports.

 The world is still falling "worryingly short of what is needed" when it comes to deploying clean energy technologies to help meet the carbon emission goals set at the Paris climate conference (COP21) in December 2015, the International Energy Agency (IEA) has warned. In its latest annual report, Energy Technology Perspectives 2016 (ETP 2016), the IEA acknowledges the significant growth in the use of renewable energy technologies, such as onshore wind and solar PV, but says overall progress is simply too slow.

Total renewable energy capacity installed currently provides around 23% of global electricity generation, sustained by progress in solar PV and onshore wind that pushed the growth of renewable energy capacity to a record high, exceeding 150 GW in 2015, according to the IEA's Tracking Clean Energy progress analysis. This is an encouraging trend, the ETP 2016 report says, and is in line with the COP21 goal to limit the global temperature increase to no more than 2°C, requiring in excess of two-thirds of electricity to be generated by renewables in 2050.

China is the largest renewable energy market, accounting in 2015 for more than half of the world’s new global onshore wind capacity and one-third of the solar PV capacity installed.  The United States maintained its position as the second largest market in the world for renewable energy, sustaining a 40% growth rate in capacity additions over the past year. In ETP 2016, China and the United States collectively account for one third of the renewable energy capacity additions to 2050 that are required to be on track to meet the 2°C goal.

Solar drive in the city

A key technology will undoubtedly be solar PV. By 2050, rooftop solar could technically meet one-third of the electricity demand in the world's cities, the IEA report says. Indeed, it will be the use of such technology in cities - particularly those in emerging and developing countries - that offers the most-cost-effective approach to limiting emissions.

"Cities are home to about half the global population but represent almost two-thirds of global energy demand and 70% of carbon emissions from the energy sector, so they must play a leading role if COP21 commitments are to be achieved," said IEA Executive Director Fatih Birol at the launch of the report during the Clean Energy Ministerial in San Francisco in June. As centres of economic growth and innovation, they are ideal test-beds for new technologies – from more sustainable transport systems to smart grids – that will help lead the transition to a low-carbon energy sector, he added.

At least two-thirds of the growth in global final energy demand to 2050 will come from cities in emerging and developing economies, the report says. Between now and 2050, a large portion of new buildings -  equivalent to 40% of the world’s current building stock - will be built in cities in emerging and developing economies which will also account for 85% of the increase in urban passenger travel globally. "Without change in current policies, that increased demand for energy services would double these cities’ energy-related CO2 emissions."

To achieve the transition to a low-carbon energy system, stronger, more ambitious policies are required across the energy sector, with further investment critical to accelerate technology development, reduce costs and facilitate deployment, the report says. "The focus on technology is crucial. It is the key to achieving the aggressive changes within the energy sector needed for the world to limit the global average temperature rise to 2°C."

Importantly, in targeting a least-cost pathway, ETP modelling and analysis does not depend on the appearance of breakthrough technologies, rather technology options employed are either already commercially available or at a stage of development that makes commercial-scale deployment possible within the scenario period. However, technology innovation is essential, for example, in accelerating technology development, reducing technology costs or facilitating market access.

In its 2°C scenario (2DS), global electricity generation is almost completely decarbonised by 2050. At the global level, the share of renewables in the generation mix increases from 22% in 2013 to 67% by 2050 (Figure 1). Coal- and gas-fired power plants equipped with carbon capture and storage (CCS) solutions reach 12% of generation in 2050, and the share of nuclear increases from 11% to 16%.

Globally, the integration of a growing share of electricity from variable renewable sources (30% by 2050 from solar PV and wind) requires increased flexibility in the electricity system. Flexible power plants on the generation side, such as combined-cycle and open-cycle gas turbines, can facilitate increased generation from variable renewables. In the 2DS, the full load hours of gas-fired capacity more than halve, from 3 300 hours in 2013 to 1 250 hours in 2050, as gas power plants are used more and more to balance generation from variable sources. Storage can also shift generation from variable renewables from times of excess supply to times of high demand. In the 2DS, the global storage capacity, mostly pumped storage, more than triples to 560 GW by 2050. Like storage, demand response moves electricity demand to times of surplus electricity supply.

A further challenge to decarbonise the electricity system is to accelerate the deployment of low-carbon technologies for generation (Figure 2). With the exception of hydropower, the deployment rate of all low-carbon technologies needs to accelerate over the next 35 years.

The highest deployment rates are needed for solar PV and onshore wind. For solar PV, for example, the deployment rate has to almost double from 27.5 GW per year (GW/yr) between 2010 and 2014 to 45 GW/yr between 2015 and 2025, a rate that according to preliminary data has already been exceeded for 2015. A further doubling to 94 GW/yr is needed for the decade from 2026 to 2035 and almost a further doubling to 189 GW/yr from 2036 to 2050. Not all of the PV capacity deployment between 2036 and 2050 increases installed capacity, as one-third of the deployment is needed to replace existing PV panels that have reached the end of their technical lifetime.

Such accelerations in deployment rates for low-carbon technologies are challenging, but not unprecedented: annual solar PV capacity additions were on average 4 GW/yr from 2005 to 2009, but grew to 27.6 GW/yr between 2010 and 2014. By supporting research and development (R&D) of alternative materials, governments can reduce the dependency on specific materials or production processes. Stable policy frameworks and targets for low-carbon technology deployment can also stimulate innovation in industry. Predictable policies are crucial in providing the confidence needed for investments in manufacturing facilities. 

A large, skilled workforce will be needed to develop low-carbon power generation technologies, build manufacturing plants and install, operate and maintain the plants. For the wind industry, a work force of around 1.4 million people would be needed in 2025 to reach wind deployment rates similar to those in the 2DS for the decade between 2015 and 2025 (67 GW/yr for onshore and offshore combined) (Lehner et al., 2012). Governments could help establish the necessary education and training activities, though competition for skilled engineers and technical staff with other industries may become a potential bottleneck.

So how much will all this cost? According to the IEA, if emissions were to be limited at 6°C, the cost would be 24% lower at USD 28.3 trillion. The major part (85%) of the additional investment is required in non-OECD countries, notably China (22%) and India (21%), due to their strong growth in electricity demand of 140% between 2013 and 2050, the IEA report says.

On a technology level, renewables combined, at USD 10.7 trillion, account for the lion’s share of the additional investments, followed by CCS (USD 2.1 trillion) and nuclear (USD 1.8 trillion).  These additional investment needs are partly offset by reduced investments in fossil power plants without CCS of USD 4.2 trillion as well as – due to lower electricity demand in the 2DS – reduced investments in transmission and distribution infrastructure of USD 2.1 trillion (compared with the 6DS). 



Gail Rajgor is a freelance journalist, editor and photographer.

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Energy efficiency  •  Policy, investment and markets  •  Solar electricity  •  Wind power