توسعه انرژی های تجدید پذیر و امنیت عرضه: تجزیه و تحلیل تجارت کردن

This paper analyzes the effects of the green transformation on the German electricity sector with respect to the energy-political triangle. It focuses on how the development of renewable energies will affect security of electricity supply. In a cost–benefit analysis, the value of supply security is compared with its costs of provision. More specifically, the benefits of maintaining the present quality of electricity supply are the avoided social damages from electricity outages and are compared with the respective investment costs in the low- and medium-voltage distribution grid. It is shown that the transformation process towards a green and decentralized production structure will be costly for society, even though the costs can be reduced by different measures.

The impossibility of any longer ignoring the problem of greenhouse gas emissions has caused a shift in energy policy worldwide. For example, the governments of all Western countries have begun to emphasize the environmental aspects of their energy policy. However, designing an optimal energy policy should not be based on a one-dimensional view. Indeed, there are three benchmarks against which each energy-political initiative should be measured: its environmental soundness, its effects on security of supply, and its impact on energy prices. These three aspects comprise what may be called the energy-political triangle or, better yet, “trilemma,” a term that has the advantage of implying potential conflicts. However, energy-political initiatives are usually studied one-dimensionally in terms of their explicit goal (see e.g., Telson, 1975), and the current situation of energy market transition in Germany is no exception. The importance of such approaches is not without value, of course, but with regard to the energy-political triangle, they are not sufficient. Therefore, using the German electricity market as an example, this paper analyzes environmentally motivated instruments with respect to their further consequences for the energy-political triangle. Designing an electricity market always involves some tension between (normative or positive) economic considerations and technical requirements and possibilities. This is especially true in the matter of supply security. From an economic perspective, a fundamental problem is estimating the value of supply security since it is not reflected in any price (BET et al., 2011 and De Nooij et al., 2007). The fact that security of supply is a public good complicates the situation: without a regulative intervention, it would be underprovisioned. As a consequence of these problems, security requirements for the net operators are mainly technically in nature (Woo and Pupp, 1992). The economic literature, however, contains a wide range of papers that estimate the social value of supply security, which is often approximated by the (social) damages of outages (see e.g., De Nooij et al., 2007, Ghajar and Billinton, 2006 and Willis and Garrod, 1996) and is the approach taken here. The different estimation methods are described later in a separate section. The obtained results imply both technical and economic considerations. For example, De Nooij et al. (2010) show how security standards based on estimating the value of supply security could replace those based on engineering practice. Thus, evaluating supply security can be seen as the first step in identifying socially optimal interruption levels (Baarsma and Hop, 2009). Furthermore, it can be used in case of shortages to optimally allocate electricity (De Nooij et al., 2007, Forte et al., 1995 and Serra and Fierro, 1997). The present analysis combines technical and economic considerations such that the social welfare effects of the technically determined transition on the electricity market can be evaluated. The analysis is based on the German electricity market, which in recent years has experienced a significant prioritization of environmental policy. The development of renewable energies is considered an appropriate way of reducing the country's CO2-emissions. Therefore, renewable energy as well as several energy efficiency goals for 2020 were defined in a national energy concept initiating a transition process on the electricity market. Unless electricity imports shall increase, the planned nuclear phase-out has put even more pressure on this project. After the transformation, the structure of the electricity market will be decentralized instead of centralized as it is currently. The renewable energies instrument designed to accomplish this transition is analyzed in this paper with respect to its effects on the energy-political benchmarks. First and foremost, the social welfare effects with respect to the supply security targets are analyzed in a cost–benefit framework based on the contributions of De Nooij et al. (2010) and Tishler et al. (2006). Then, the paper goes one step further than, to the author's knowledge, most supply security analyses by comparing the value of supply security with its costs of provision. Based on that comparison, conclusions are drawn with respect to the climate targets and their effects on electricity prices. The paper is organized as follows. Section 2 analyzes targets and measures of the transformation process in the German electricity market with respect to the year 2020 from the perspective of the energy-political triangle. The cost–benefit analysis follows in Section 3. After presenting the methodological approach in Section 3.1, the necessary cost and benefit parameters are calculated in 3.2 and 3.3. Then, in Section 3.4, the resulting net present value is derived. Section 4 summarizes and discusses the results, draws conclusions, and discusses future research areas.

In Germany, the development of renewable energies is almost unanimously believed by politicians and the public to be the most promising approach to reduce the country's CO2-emissions and combat climate change. The present paper focuses on the welfare effects of maintaining the current level of supply security given the large-scale integration of green power into the energy system and quantifies the effects of the resulting trade-off. In a cost–benefit analysis, the discounted cash flows of the benefits of maintaining the high level of supply security and of the costs of grid investments are compared. The benefits were calculated as the avoided damages of a decreasing quality of supply security that would occur in case of a ceteris paribus development of renewable energies. They result from an increase in the average (per year) outage duration for each consumer served (SAIDI). The resulting lost load was evaluated with a production function approach. The investment costs of the associated grid expansion of the distribution grid are calculated by BET et al. (2011). The net present value shows that the costs by far exceed the induced welfare gains of maintaining a constant supply security level. Regarding the climate goals associated with the energy-political triangle, the efficiency of the instrument is controversial. Due to the interrelation of the EEG with the European emissions trading system (ETS), much literature finds, for example, Sinn (2012), that the net effect of the EEG-implied emissions reduction is zero. Since the latter covers almost 100% of European electricity production, a decreasing demand for emission certificates in Germany induced by renewable energies development reduces the certificate prices and thereby increases the demand for certificates in other ETS countries by about the same amount. This certificate price decreasing effect reduces not only the competitive ability of renewable energy technologies which do not receive specific public support. It also supports the competitive ability of the technologies emitting most CO2 as for example coal (see Böhringer and Rosendahl, 2010). Based on this effect, Sinn (2012) emphasizes that other countries' CO2-emissions are subsidized by for example Germany's abatement efforts. Additionally, welfare losses arise due to unequal price effects between the German EEG-based abatement and the other countries’ ETS-based abatement. Sinn (2012) points out that the German renewable energies development creates welfare losses since it leads to a cost-inefficient abatement of CO2. On the one hand, different feed-in tariffs for different technologies induce varying marginal abatement costs of CO2-emissions. On the other hand, the German abatement is inefficiently high compared to other ETS countries' CO2 abatement based on ETS certificate prices.11 Beside the effects already discussed, further effects regarding the price target may be considered. An example is that increasing the amount of renewable energy in the electricity system avoids costs of ETS emission certificates. However, this effect is negligible due to the low certificate prices we are facing in the current trading phase and the renewable energies levy (EEG-Umlage), the EEG-induced marginal abatement costs distributed among the (non-privileged) end users amounting up to 5.28 ct. per kWh in 2013 by far exceed the avoided certificate costs. Nevertheless, there is a potential effect due to the interrelation of EEG and ETS that may not be neglected. Additionally, mainly due to higher grid fees and the renewable energies levy, society suffers, not only in the matter of efficiency as described before but also with regard to the distributive goals (see e.g., Sensfuss and Ragwitz, 2008 and Techert et al., 2012). Thus, the analysis implies that the strong focus on the development of renewable energies in Germany, accompanied by a strict grid regulation, results in a triple trade-off with regard to environmental, price, and supply security considerations (for a more detailed discussion about the interrelation between the different regulative systems, see for example, Böhringer and Rosendahl (2010)). However, since the analysis is of partial nature, further aspects must be taken into account when analyzing the results to obtain a complete picture. This can be regarding the dynamics between the different electricity grid levels influencing the grid development costs or regarding avoided maintenance costs due to the grid development. Also of interest are the interrelations between grid investments and the probability of large-scale power blackouts. Additionally, the long term effects of such investments instead of the short to medium term effects may change the trade-off results. Also the effects of an increased production of green energy on the international energy markets as well as the interrelations between EEG and ETS must be taken into account in more detail to analyze the complete effects of the green energy development regarding the energy-political triangle. The results cannot simply be dismissed as the “natural” outcome of a trilemma between different energy-political goals but as a specific consequence of a deliberately chosen energy-political strategy. For example, to reduce CO2-emissions at the national level, choosing a more diversified set of instruments can to some extent result in welfare gains. Take the example of energy efficiency: if energy efficiency cannot be improved, the increasing use of renewable energy becomes much more expensive and the social costs of the transformation process increase. This may be because more back-up power has to be provided or because increasing energy efficiency decreases load density and therefore increases foregone interruption damages. Of course, also in this context, cost–benefit considerations are necessary to optimize the measures. Consider, for example, the possible consequences of a more economically (and less technically) oriented grid regulation. Regarding the negative net present value of the analysis, the question arises as to whether regulation may be too strict for socially optimal investment by network operators. Given the renewable energy development plans, more flexibility in the supply security goals (which are implied in the technical guidelines for the grid operators and can be interpreted as maintaining the current quality of supply security) could be welfare increasing. Moreover, regarding the welfare effects of delays in the (distribution) grid development, postponing grid development and therefore investment costs may, at least to some extent, be welfare enhancing in the analyzed situation. Moreover, the energy-political triangle is exactly what its name implies-political. Conflicts among the targets arise from the mixture, or maybe even confusion, of different positive and normative demands within the triangle. An alternative target (set) could partially circumvent the problem. For example, it is well worth considering an instrument analysis solely based on the claim of efficient electricity prices since that would subsume different aspects of the energy-political triangle, for example, the internalization of climate externalities as well as several competitive effects. Since efficient prices should include the total social costs of electricity production and distribution, aspects of structural supply security would also be covered. Such a consideration could, for example, take place as a component of grid fees, which could contain the costs of providing this public good. Even if such a requirement does not satisfy all political demands, for example, those having to do with equitable distribution, it seems that some conflicts could be avoided and it might serve as a better orientation guide. Clear benchmarks in this context are of particular importance due to the absence of market signals. This is most problematic regarding the determination of the optimal level of supply security, which is almost completely dependent on the national regulatory situation since the electricity grid, which provides supply security, is a natural monopoly and strictly regulated in Germany. The present analysis implies that the conflict between the development of renewable energies and supply security is based on an imprecise differentiation between the climate instruments and the climate goals. Therefore, a clearer specification of the goals themselves in the sense of the target indicators and an examination of the instruments regarding them is essential to avoid inefficiencies. The strong focus on a renewable energies development, which overlooks the consequences regarding the energy-political triangle, for all with regard to the climate goals but also with regard to the negative net present value and price effects, indicates that a proper examination in terms of targets, target indicators, and instruments has not taken place in Germany. The consequent inefficient instrument choice and transition process are reflected in the follow-up costs analyzed in this paper. Even though the complexity of different energy-political demands makes finding a first-best solution difficult, if not impossible, the chosen instruments do not appear to be even a second-best solution. Therefore, what is needed, but is beyond the scope of this paper, is an open and broad social discussion about the future energy market in Germany. Especially important is a more precise definition of energy-political goals (and indicators) and instruments. Such a discussion must cover a wide range of issues, including not only the development of renewable energies as a potential means on efficiently meeting climate targets but also the impact of the nuclear phase out and the consequences of integration of the European energy markets. This paper is intended as a contribution to this essential discussion. There are several possible extensions of the approach taken in this paper. Since the present results indicate that incentive regulation and technical standards have to be sufficiently flexible to ensure an efficient electricity market development, the role of regulation should be further analyzed as it is of great importance for the whole transformation process. Moreover, future research is especially needed on the relationship between the development of renewable energies and energy security. Also conceivable is an estimation based on an explanatory variable that could be used in addition to or instead of load density to estimate the relation between grid structure, production structure, and supply security. Finally, further research is needed with regard to the phasing out of nuclear energy and the resulting effects on supply security and emission reduction goals.