Thursday, 22 June 2017

Why cannot renewables replace such fossil fuel like natural gas?

Ten years have passed since the European Commission put forward proposals for a reduction in greenhouse-gas emissions in 2007. These proposals, later on, formed the basis for the strategy well known as the EU 20-20-20 strategy, which made it necessary to review different energy resources taking into consideration not only fundamental evaluation criteria for different energies such as efficiency, natural resource base, their availability, security of supplies and energy storage requirements. The EU 20-20-20 strategy attached a particularly great importance to environmental impacts of energy sources. In this regard, one of new environmental targets was to reach 20% of renewable energy in the total energy consumption in the EU by 2020.
The EU Member States have made significant progress in promoting development of renewable energy sources (RES) over the past years. According to the last year's report of the European Environment Agency, the share of gross final energy consumption to come from RES rose to 16.4% in 2015 from 16% in 2014. The Second Report on the State of the Energy Union issued on 1 February 2017 contained the same data and showed that it helped to decouple economic growth from greenhouse gas emissions - during the 1990-2015 period, the EU's combined GDP grew by 50%, while total emissions decreased by 22%.

It is worth recalling however, that apart from alarming climate changes another reason why RES have become a focus of special interest is the declining national potential of primary fossil energy resources in the EU member states. According to Eurostat, in the decade between 2004 and 2014 the production of renewables increased by 73.1%. By contrast, the production levels for the other primary sources of energy generally fell over this period, the largest reductions being recorded for crude oil (-52.0%), natural gas (-42.9%) and solid fuels (-25.5%), with a more modest fall of 13.1% for nuclear energy.
It would seem that the reduction in local production of conventional primary energy should not cause any problems if instead of them consumers in Europe have a possibility to switch to RES. Experience has shown, however, that along with the obvious advantages, RES have revealed some serious weaknesses in operation – it is unstable and fluctuating power supplies. By an unlucky coincidence, those problems became apparent exactly ten years after gaining an official recognition when in January 2017 Europe experienced a sharp fall in output of RES generating capacities.
It is unlikely to find a rational person in Europe, especially in the northern part of the Continent, who would need an explanation of how much stress an unstable energy supply can cause during a winter cold spell. Fortunately, the present generations of European citizens have almost never encountered such problems. Meanwhile, to give everybody an opportunity for imaging such an energy breakdown in winter the German daily "Die Welt" tried to describe the picture of snow-covered solar panels and drooping blades of wind turbines by using an old word Dunkelflaute, which refers to that time of year, when neither sun nor wind occur in necessary abundance.
"Dunkelflaute could be pushing Germany's power supply to its limits," says the title of the article published in Die Welt on 6 February 2017. Let us notice that is what happened in the EU member state with well-advanced energy sector, which in all circumstances is capable not moving beyond that critical boundaries and avoiding unscheduled interruptions in the power supplies. This was possible thanks to the prompt switching over to conventional energy sources to substitute RES when the latter significantly cut their contribution to gross final energy consumption.

According to statistics from the Berlin-based institute Agora Energiewende, by the end of January 2017 as much as 90% of the country's power was provided by coal, gas and nuclear. The chart below illustrates that on 24 January 2017 the generation of electricity by onshore wind power in Germany dropped to its historic minimum 0.486 GW. Later the electricity production by onshore wind returned to the pre-crisis level and after about six months on 7 June exceeded 23 GW.
As Stefan Kapferer, Managing Director of the Federal Association of the Energy and Water Industry (BDEW) told Die Welt, the past January saw a combination of lower-than-average temperatures, a high demand in electricity and extreme fluctuations in input from wind and solar power. "Flexible, conventional power stations are essential if we are to stabilize the electricity network," he said. "We have to be able to cover energy demand regardless of the weather."

Kapferer further noted that all this pointed to the need for flexible gas and coal power stations. Particularly in this case there would be an opportunity to "integrate renewables into the energy provision system," so they become "supporting pillars" of supply.
The January’s green electricity generation crisis requires differently looking at implementation of the Energiewende concept to perform the transition by Germany to a low carbon, environmentally sound, reliable, and affordable energy supply. The target was introduced of a 40–45% share of renewable energy in gross electricity consumption in 2025 and then in ten years achieve 55–60% in 2035. In 2015, as reflected in the figure below, the share of green energy accounted for about 30% mostly produced by wind and solar power.

Meanwhile the increasingly obvious problem of RES insufficient reliability no doubt weakened their position in favour of brining conventional energy sources into sharper focus. In addition, there will now be caps on the amount of green power eligible for subsidies what makes them even more uncompetitive.
It is important to note, however, that although the crisis of wind and solar generation, which had arisen in January, was successfully resolved by increasing the contribution of coal, gas and nuclear stations, in fact only natural gas has clear comparative advantages within this energy triad. As to the future of coal power, it indeed has poor prospects because further decarbonization should expel solid fuel from heat and energy balance in most EU member states. According to the report prepared by experts of the Berlin institute Climate Analytics, the EU will exceed its Paris Agreement-compatible emissions budget for coal based electricity generation by 85% in 2050 if all existing coal-fired power plants continue operating to the end of their full life span. Analysis suggests 25% of currently operating coal-fired power units need to be shut down by 2020, rising to 72% by 2025, before a complete shutdown by 2030.
Nuclear energy will have equally challenging future because its reputation has not been restored after Fukushima and Chernobyl nuclear disasters. According to a recent Greenpeace survey, 85% of Germans over 45 years old believe a disaster similar to Chernobyl could take place in Europe. Now anti-nuclear tensions are arising from the growing number of recent terrorist attacks in Europe that may have made their situation even more difficult.
In this regard, it's not hard to see that RES are going to compete for this emerging market niche, further increasing their share in the energy mix in Germany. However it is evident that this can be done effectively if renewables in Germany pair with natural gas, which, as in the January case, should assist to strengthen resilience of energy system as a whole especially against the vagaries of the weather.

An example of this collaboration between two kinds of energy has already excited in the United Kingdom where energy business are making progress in exploiting the advantages of natural gas in comparison with other primary energy sources. They include flexibility of supplies and responsiveness reflecting fluctuations of actual daily demands in the gas market, all-weather capability, technological opportunity to create significant reserve and emergency stock to overcome current uneven distribution and seasonal variations in demand, much higher environmental safeness incomparable with other fossil energy resources, competitive prices and transportation costs, development of NGV fuel markets, etc.
So guided by the classic SWOT analysis (analysis of strengths, weaknesses, opportunities and threats) it should be noted that natural gas can be considered not only as RES close rival but to a much greater extent as their partner, which can compensate energy consumers for still existing weaknesses of the latter. Of course, partnership conditions can change initiating an impact on the future energy mix.

Meanwhile, those who doubt whether such a partnership between RES and natural gas is possible especially emphasize that EC member states actually do not have their own natural resources of this fossil fuel. In that regard, it is worth pay due attention to the report prepared by the Oxford Institute for Energy Studies in January 2017, which argues that "the European gas industry has reason to panic about its future up to the mid-2020s. Falling domestic production will mean that additional gas will continue to be needed (and will be available) from upstream producers and exporters". Clearly, in the foreseeable future of natural gas imports by the EU member states much will depend on whether RES can be enough competitive and on further development of innovative technologies of storing large volumes of electricity.

Why do not admit any realistic sustainable scenario of economic development, as if shaped by the laws of physics, should have several energy pillars where natural gas shall be deemed to provide one of prospectively vital resources along with RES?

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