Chapter 10

Likelihood of and Timeline for a World Powered by 100% Renewable Energy

10.1 Likelihood of a 100% Renewable World

It is my firm belief that if we only highlighted negative stories like global warming and finiteness of resources – as true as it is – in order to discuss a change from today’s centralized fossil and nuclear energy supply, it would take quite long to get a global change organized. I am convinced, however, based on the superior cost development of all renewables compared to today’s traditional energies that the financial argument, once understood by decision makers in politics, the financial institutions and industry, will make this change much quicker than most people would anticipate today.

The preceding chapters aimed to quantify the competitiveness of the most important renewable energy technologies in an energy efficient world. Besides the technology developments which most likely are the easiest to achieve there are some additional facts which are very often overlooked.

One important finding was developed by Stern in his famous report [10-1] which described the investments necessary for a renewably powered world compared to the damage which will occur due to climate changes if we continue to burn fossil and nuclear resources. He concluded that the damage was greater than the cost and the world would be in a worse shape by continuing with business as usual – melting of glaciers, rising sea levels with flooding in many highly populated regions, damage by stronger tornados, hurricanes and typhoons. In the latest report by the IPCC from September 2013 the increase of weather extremes and a quicker rise of the sea level compared to earlier reports strengthen this argument.

There has been and will be in the coming years a heavy debate on which of two very different concepts will be superior: When looking at past developments in most developed countries in the OECD world there has been a shift from an originally decentralized energy production in the 19^th century towards centralized energy production, particularly for electricity generation. Big utility companies developed in many countries in the 20^th century and dominated the energy infrastructure in these countries. Parallel to this development the “One-Way-Flow” of electricity from the big power stations via the various grid infrastructures to the consumers was established. We begin to realize as already discussed in a preceding chapter that the integration of renewables, in particular Photovoltaics with its decentralized nature, will need a much more decentralized infrastructure with a “multidirectional” flow of electricity to and from “prosumers”⁹, still combined with larger power generating systems. It is easily understood that the larger the area is to produce electricity from renewables like wind and solar, the easier it will become to satisfy a respective load curve with less storage capacity. As it is not yet clear what generation and storage cost can be achieved in future years there is no clear cut answer to decide whether a Europe wide grid infrastructure together with large off-shore wind parks in the North and along the coast lines and green field PV parks in southern regions will have an economic advantage over a much more stringent decentralized production portfolio within areas with – for simplicity’s sake – a radius of ~100km each. This would require considerably more storage, especially to cover the seasonal changes. The seasonal storage has the intrinsic disadvantage that one has to transform electricity into a storable energy form, for instance through electrolysis to produce hydrogen, which entails considerable losses. It makes a lot of sense to go ahead with the project P2G (“Power to Gas”), which uses electricity from renewables produced at times when the grid cannot absorb these kilo- to Terra-Wh and to transform them into methane via hydrogen plus CO₂ which can easily be fed into the existing natural gas pipeline infrastructure.

10.2 Global Network or Local Autonomy?

10.2.1 The Concept of a Worldwide Super Grid Versus the Hydrogen Economy

Moving towards a world which is powered at 100% by renewable sources needs additional features. Wind and solar are the most powerful and most cost effective ones but both have a strong seasonal and daily variation. The compliance with the load curve to be satisfied is an important aspect.

As early as in 1874 Jules Verne developed the vision of replacing the burning of coal with hydrogen and oxygen as a source of energy [10-2]. The term hydrogen economy was first used by John Bockris in 1970 and further developed together with Eduard Justi [10-3] in 1975 at a time when electricity transport was associated with high losses over large distances. Hydrogen is an elegant secondary energy which can be produced via electrolysis from water, stored over long periods of time and then be used either by combustion to produce power and/or heat or alternatively electricity through fuel cells. This is all correct and technically feasible and demonstrated but overlooks a simple fact: the losses associated with the hydrolysis and, if electricity is needed, the additional losses due to the conversion back by fuel cells. If we are not using laboratory numbers we may assume a loss of about 30% for both steps – this means that for one unit of electricity produced by renewables only half a unit of electricity remains after the twofold transformations (0.7 × 0.7 = 0.49 or ~50%).

With the advent of HVDC, grid lines which operate very reliably today as subsea cables incur losses of only about 4 to 5%-points for every 1,000 km of transported electricity. As this technology will still improve in the future through technology development – higher voltages, improved cables and transformation processes – I foresaw a great future. The basic idea, summarized in Figure 10.1, which I developed in the early 1990s when I had to give a talk after a renowned advocator of the hydrogen economy is the following:

• If we start in a region that is open for a new way of energy supply and distribution, we may do this in Europe, enlarge into the Middle East and later into North Africa (EUMENA region). Such a grid would already span a time difference of about 4 hours, which would make it possible to use electricity produced in Eastern countries like Turkey in the early hours of the afternoon during the morning peak hours in countries like Great Britain. Of course all other renewables like wind from all areas would contribute effectively to satisfy the load curve. Such a development cannot be carried out in a few years but would realistically need a few decades. I was quite pleased when 20 years later the concept of an EUMENA Super Grid was taken up by the project DESERTEC. While I liked this part I was not at all satisfied with the project as such. The main reason for this is that when the project was announced in 2009 by the DESERTEC Foundation there was a lot of support from major utilities companies which liked this idea a lot as they could argue to be in favor of renewables, as they were using solar in more sunny areas like North Africa compared to Germany and would thereby stop the unwanted decentralized electricity producing systems in our own country – which take business away from them. In the meantime the Desertec Industry Initiative (DII) is focusing more of the production of renewable Electricity and its usage in the nearby region.
• The next region could be the NAFTA area (2) connecting the US and Mexico
• Several Asian regions (3) could then follow – or be developing in parallel to the NAFTA area
• Australia could follow (4)
• South America and Africa may complement the regional Super Grids (5)
• The last step could then be the connection (6) of the then existing regional Super Grids 1 to 5. This would allow the daily (East-West) as well as the seasonal (North-South) exchange of produced electricity with the regional load at a global level.

Figure 10.1 World Wide Super Grid as an alternative to a Hydrogen Society.

Many argue that such a worldwide grid is unrealistic because it would need too many countries to cooperate and because of its vulnerability. This argument, however, forgets what has been already achieved globally in the last decades with the development of gas pipelines and global oil tanker routes. If one plots these routes with a thickness proportional to the annually transported energy equivalent, there would be only a few very thick lines and everyone accepts the vulnerability of such concentrated transports. The very positive element of a World Wide Super Grid shown in Figure 10.1 would be the multitude of grid lines – and not only the few ones shown – which would actually develop as a function of time. This would be much less vulnerable than today’s situation. In addition it may be anticipated that as more and more countries realize the benefit of such a worldwide grid there would even be a desire to be part of it in order to gain access to a less costly energy supply for each and every one.

In addition, the losses associated with transporting either hydrogen or electricity are at least similar, most probably higher with hydrogen. Last but not least, the Worldwide Super Grid would not need large storage infrastructure, especially for seasonal storage. Although this worldwide Super Grid looks the most elegant there may be possibilities to even accelerate a 100% renewably powered world, as will be discussed in the next chapter.

10.2.2 New Horizons with Optimizing Regional 100% Renewable Energy Supply

It is interesting to observe how new technology developments and insights can influence and change one’s own picture and perception. When I started my career in PV in the late 1970s, it was not foreseeable that wind and solar would develop as quickly as they did in reality. The concept of a (northern!) country like Germany to have a significant contribution of secondary energy delivered economically mostly by PV and wind as early as 2030 was simply out of reach. Should, however, the technology development which we experienced so far continue – which is more probable than not – we would be able to discuss completely new global concepts for energy supply more than ever before and this would make the global 100% supply by renewables even easier and more quickly doable.

By our own country experience in Germany we know how difficult and lengthy the process is of getting approval for a new HV transmission line. Approval procedures for enhancing the grid connection between Spain and France took about 20 years. It will doubtlessly be even more difficult – not technically, but due to approval procedures – when it comes to the interconnection of the various regional Super Grids shown in Figure 10.1 as indicated by the connecting lines (6). As a consequence, it may take several decades longer to introduce a global 100% renewable energy supply using this Worldwide Super Grid than it would take to individually build up 100% or only 90+% renewable energy supply in the regions 1 to 5 as shown in Figure 10.1.

If a more advanced sub region could demonstrate that a 100% renewable supply is superior both in terms of environmental as well as economic costs, then this could trigger a much faster spread for the 100% global renewable supply rather than a situation in which the regions have to wait until the interconnections are up and running. In the meantime they still have to use traditional fossil energy for their secondary energy supply.

10.2.3 Local Autonomy: Silver Bullet for the Decentralized Private and SME Sector Plus the Centralized Energy Intensive Industry

I would like to again give credit to Wolf von Fabeck, the mastermind for the support scheme “cost efficient feed-in tariff”, who in recent times advocated for a strict local autonomy without additional transmission lines. The more I engage in the 100% RE scenario the more I appreciate the local autonomy – at least for the private and SME/office sector. Sometimes it may help to bring ideas together which today are still seen as irreconcilable antipodes. Today, the discussion is taking place in the traditional sector that the major energy contribution should come from wind off-shore which needs many additional transmission lines to connect to the centers of usage of energy far away from the costal lines in many countries – like Germany. Secondarily it is often argued that the energy intensive industry suffers disproportionately from the more expensive small and decentralized renewable energy production systems.

There is a simple loophole to escape from this dilemma, especially when thinking on a global scale. Like the aluminum production in Iceland where bauxite (aluminum ore) is transported with ships to a hydro plant, or the reduction of quartz to metallurgical silicon in Scandinavia which also takes place near a hydro power station, I could imagine a development in which energy intensive industries not only settle near to hydro power stations but also near to the coast where off-shore wind parks provide electricity or large solar thermal and PV plants in sun-rich areas deliver electricity and/or process heat, especially if such places can be easily reached by ship transport. At the end it will be the economic decision whether to transport electricity from large central power stations to energy intensive industries or to transport material to be processed to the power stations. Either way such a development would take away a lot of unnecessary discussions which we are having today. Such a relocation of industrial companies would fortunately not imply that countries would have to give up those industries but only that they would have to make use of the respective natural resources.

In contrast to this future “local autonomy for energy intensive industries at places of centralized renewable energy production plants”. we will have in parallel the “local autonomy for the private sector and regional energy needs for offices and SMEs”. The latter can well be equalized with the future smart grid areas that were discussed earlier.

10.3 Timeline for a 100% Renewable World

“Strive for Mission Impossible and be surprised”; with Mission Impossible being 100% global energy supply through renewables by 2050. I am realistic enough to know that most probably this “100%” will not be reached. However, if in selected regions we now start working towards this plan locally, we may be surprised to see that other regions may quickly follow once they realize the economic and environmental benefit in the first region. Yes, the front runner may have the burden of having spent more money on this conversion process for each power and energy unit compared to the followers – but it may also have the advantage of more quickly growing an industry to serve these energy markets with all the required products and services everywhere.

It may be helpful to also address the question of the timeline by looking at how in the past the global industry has developed (we already mentioned earlier such an analysis of the timely development of secondary energy forms by Marcetti). Three different timescales are discussed in this area: short economy cycles ranging from between 3 and 7 years (“Kitchincycles”), medium term economy cycles of up to 11 years (“Juglar-cycles”) and the often discussed long time cycles of about 50 years, introduced by the Russian economist Kondratieff in the 1920s which he called “the theory of long waves”. Joseph Schumpeter renamed this phenomenon “Kondratieff – cycles”. In analogy this methodology was extrapolated by economists like L. Nefiodow [10-4]. The development and the major contributing technologies are schematically shown in Figure 10.2. Sometimes two of the 50 year cycles are also condensed into ~100 year cycles and highlighted as times for the 1^st, 2^nd and 3^rd industrial revolution. The first phase is characterized by the basic innovation of the steam engine for mass production in the textile industry, and the introduction of the railway with the advent of mass transportation of people, materials and products. The second phase saw electricity, steel production and chemistry as basic innovations; with the automobile, driven by petrol, the development of individual transport. The third and still on-going phase started with the introduction of information technology, e.g. the internet, and the topic of “health for mankind” in a broader sense: not only in a narrow medical and constitutional sense but also psychologically, ecologically and socially. In this context environmental technologies like the introduction of renewables, energy efficiency, new transport technologies (like e-mobility), new materials and many more should also be named.

Figure 10.2 Technology cycles from the past to the future.

Extrapolating the duration of ~50 years for each Kondratieff cycle one could speculate that the running 6^th cycle may peak in ~2050 and then develop into something new – the 7^th Kondratieff cycle with radically new ideas on how the 10 billion people may live in harmony after the accomplishment of the 6^th cycle: affordable energy from renewables without any destruction of nature and new materials made by nanotechnology without any limitation due to scarcity. The start of this 7^th Kondratieff cycle could then be the start of a new and fourth industrial revolution with new materials and technologies we can only speculate about today. Whatever this future will bring, it could tell us at least that with the termination of the 6^th cycle the energy question with respect to sustainability, ecology and economy will be solved by the second half of this century. It is my firm belief that this solution will no longer consist of traditional energy providing technologies based on fossil and nuclear, but will be based on the portfolio of renewable technologies.

Another important aspect for a quick change towards a 100% renewable energy world was elaborated by Nicholas Stern [10-1]. In his famous review he postulated that it will be far more expensive to continue with business as usual (BAU) compared to quick actions to stabilize the CO₂ concentration. In short, it was stated that only 1% of global GDP is needed annually to keep the temperature increase at around 2°C until 2100 compared to costs caused by damages to in a BAU model which would be 5 times higher with a potential of even being 20 times higher! Of course these numbers strongly depend on assumptions such as long term discount rates, considered time scales and much more. Some critical opponents like W. Cline [10-5] claim that some of the assumptions are too optimistic and overestimate the above stated advantages, yet they still come to the same basic conclusion that it costs more for BAU compared to investing in CO₂ stabilization technologies such as renewables. Of course, there are also people like J. Delingpole who may be an excellent writer and journalist and, according to “The Telegraph”, the author of fantastically entertaining books. However, he unfortunately belongs to the kind of people who simply deny the findings of Nicholas Stern in a similar way as was described earlier in the case of the Climategate group which argues against global warming by man-made actions. To me this type of cynicism does not add to a decent discussion on such an important topic. Fortunately we live in a part of the globe where everyone can have their own opinions and can make them public without fear of punishment. But that freedom should not be misused to disqualify other opinions just by a mixture of half-true statements and discrediting other people.

More specifically I could foresee the following chronological development:

• By the latest in the 2020s, all of the described and necessary renewables such as decentralized PV, centralized CPV and CSP, wind on- and off-shore, solar thermal as well as all other renewables will have demonstrated their superiority over traditional fossil and nuclear technologies.
• Storage solutions which will both help e-mobility and fluctuating renewables to cover increasing shares of the energy needs of countries will also be available in this time frame.
• In some regions supranational HVDC transmission lines will gradually be added in the 2020s and 2030s to efficiently distribute the electricity from large wind off-shore and CPV / CSP plants. Alternatively we may see the relocation of energy intensive industries to be closer to the large centralized PV and wind power plants.
• The developments described above will not happen in any place or region around the globe now or in the coming years. The frontrunners will be Europe, the US, Japan and China and it will be then a question of time until more and more other regions will recognize the monetary advantages of introducing renewables and replacing traditional energy sources.
• Ideally the global energy could be served renewably at 100% in 2050. If energy efficiency measures could be accelerated so that only the lower boundary of 90 PWh is needed, this could already be achieved even earlier. However, as most often in the real world, existing systems – like traditional fossil and nuclear power plants – and traditional behavior will most probably and unfortunately prolong this time scale. But the bigger the gap between the lower cost of renewables and the high cost of traditional energies will become, the quicker it will happen.

⁹ This is the combination of what households in the future will be, namely producers and consumers = “prosumers” of electricity