Electric Vehicles: Charging into the Future

Electric vehicle drives offer a number of advantages over conventional internal combustion engines, especially in terms of lower local emissions, higher energy efficiency, and decreased dependency upon oil. Yet there are significant barriers to the rapid adoption of electric cars, including the limitations of battery technology, high purchase costs, and the lack of recharging infrastructure. With intelligently controlled charging operations, the energy needs of potential electric vehicle fleets could be covered by existing German power plants without incurring large price fluctuations. Over the long term, electric vehicles could represent a sustainable technology path. In the short to mid-term, however, exceedingly optimistic expectations should be avoided, especially with respect to the reduction of greenhouse gas emissions. Electric vehicles as such will not be able to solve all current problems of transportation policy. Yet they may constitute an important component of a larger roadmap for sustainable transportation.Transportation, Electric vehicles, Electricity markets

Frequency and duration of low-wind-power events in Germany

In the transition to a renewable energy system, the occurrence of low-wind-power events receives increasing attention. We analyze the frequency and duration of such events for onshore wind power in Germany, based on 40 years of reanalysis data and open software. We find that low-wind-power events are less frequent in winter than in summer, but the maximum duration is distributed more evenly between months. While short events are frequent, very long events are much rarer. Every year, a period of around five consecutive days with an average wind capacity factor below 10% occurs, and every ten years a respective period of nearly eight days. These durations decrease if only winter months are considered. The longest event in the data lasts nearly ten days. We conclude that public concerns about low-wind-power events in winter may be overrated, but recommend that modeling studies consider multiple weather years to properly account for such events.Comment: This is an update version after peer revie

Power from the Desert: Not a Mirage

Energy policy is confronted by two major challenges. First, fossil fuels will become ever more scarce and expensive in coming years, a trend which will intensify conflicts for the control of natural resources. Second, the burning of fossil fuels-particularly coal-is leading to an increase in harmful greenhouse gas emissions. To address these challenges, the share of renewable energy in total energy consumption must be considerably increased. In sharp contrast to fossil fuels, which are becoming ever more depleted, renewable energy sources are essentially inexhaustible. Furthermore, renewable energy produces hardly any greenhouse gases. The large-scale exploitation of solar energy for power generation offers enormous potential. In theory, solar-thermal collectors installed in North Africa over an area roughly the size of New Jersey could meet all of Europe's electricity needs. The construction of high-voltage direct current (HVDC) lines would be necessary to import power from the Mediterranean region without excessive transmission losses. An expansion of European electricity networks could also yield supplementary benefits, including enhanced integration of domestic renewable energy (such as wind power), and improved competition in electricity markets.Electricity trade, Solar energy, DESERTEC

Mitigation of Methane Emissions: A Rapid and Cost-Effective Response to Climate Change

Methane is a major anthropogenic greenhouse gas, second only to carbon dioxide (CO2) in its impact on climate change. Methane (CH4) has a high global warming potential that is 25 times as large as the one of CO2 on a 100 year time horizon according to the latest IPCC report. Thus, CH4 contributes significantly to anthropogenic radiative forcing, although it has a relatively short atmospheric perturbation lifetime of 12 years. CH4 has a variety of sources that can be small, geographically dispersed, and not related to energy sectors. In this report, we analyze methane emission abatement options in five different sectors and identify economic mitigation potentials for different CO2 prices. While mitigation potentials are generally large, there are substantial potentials at low marginal abatement costs. Drawing on different assumptions on the social costs of carbon, we calculate benefit/cost ratios for different sectors and mitigation levels. We recommend an economically efficient global methane mitigation portfolio for the year 2020 that includes the sectors of livestock and manure, rice management, solid waste, coal mine methane and natural gas. Depending on assumptions of social costs of carbon, this portfolio leads to global CH4 mitigation levels of 1.5 or 1.9 GtCO2-eq at overall costs of around $14 billion or$30 billion and benefit/cost ratios of 1.4 and 3.0, respectively. We also develop an economically less efficient alternative portfolio that excludes cost-effective agricultural mitigation options. It leads to comparable abatement levels, but has higher costs and lower benefit/cost ratios. If the global community wanted to spend an even larger amount of money - say, $250 billion - on methane mitigation, much larger mitigation potentials could be realized, even such with very high marginal abatement costs. Nonetheless, this approach would be economically inefficient. If the global community wanted to spend such an amount, we recommend spreading the effort cost-effectively over different greenhouse gases. While methane mitigation alone will not suffice to solve the climate problem, it is a vital part of a cost-effective climate policy. Due to the short atmospheric lifetime, CH4 emission reductions have a rapid effect. Methane mitigation is indispensable for realizing ambitious emission scenarios like IPCC's "B1", which leads to a global temperature increase of less than 2°C by the year 2100. Policy makers should put more emphasis on methane mitigation and aim for realizing low-cost methane mitigation potentials by providing information to all relevant actors and by developing appropriate regulatory and market frameworks. We also recommend including methane in emissions trading schemes.Methane, mitigation, climate change, cost-benefit analysis

Methane: A Neglected Greenhouse Gas

Methane is a greenhouse gas that gets far less public attention than carbon dioxide. This is entirely unwarranted. Being 25 times more potent than carbon dioxide in trapping heat in the atmosphere, methane accounts for about one-sixth of all anthropogenic (i.e. human-induced) greenhouse gas emissions. Methane is also overlooked when it comes to taking concrete measures for climate protection, despite the fact that reducing methane emissions is potentially cheap. Major sources of methane emissions are livestock farming, the natural gas sector, landfills, wetland rice cultivation and coal mining. In many cases, it is possible to mitigate substantial amounts of methane in a cost-effective way. Moreover, captured methane can be used for generating heat and power. In other words, abating one ton of methane emissions is sometimes cheaper than abating an equivalent amount of carbon dioxide. The challenge is to effectively incorporate cutbacks of methane gas emissions into climate policy strategies.Methane, Mitigation, Climate policy

Energy and Climate Policy: USA Continues to Trail behind, Despite Positive Change

In the course of current climate negotiations, the world is watching the United States in particular. Together with China, the U.S. is by far the largest emitter of greenhouse gases. Real progress in protecting the global climate requires substantial action on America's part. The U.S. has the potential to significantly reduce emissions. Per capita energy consumption in the U.S. is still about twice that of Europe. An assessment of current energy and climate policies in America is disillusioning. So far, federal and state measures have had only limited success - both in terms of increasing energy efficiency and in the use of renewable energy. While some regional initiatives are promising - for example, the establishment of renewable portfolio standards, or emissions trading schemes in the Northeast and West of the country - they ultimately lack sufficient ambition and scope. Proposals currently under debate in Congress for a national energy and climate protection law are highly contested, even though they do not set particularly demanding goals for reducing emissions in the medium term. Against this backdrop, the U.S. cannot be expected to catch up anytime soon in the area of climate protection.Climate Policy, Energy Policy, Renewable Energy, USA

Regulated Expansion of Electricity Transmission Networks: The Effects of Fluctuating Demand and Wind Generation

We study the performance of different regulatory approaches for the expansion of electricity transmission networks in the light of realistic demand patterns and fluctuating wind power. In particular, we are interested in the relative performance of a combined merchant-regulatory mechanism compared to a cost-based and a merchant-like approach. In contrast to earlier research, we explicitly include both an hourly time resolution and fluctuating wind power, which allows representing demand in a very realistic way. This substantially increases the real-world applicability of results compared to previous analyses, which were based on simplifying assumptions. We show that a combined merchant-regulatory regulation, which draws on a cap over the two-part tariff of the Transco, leads to welfare outcomes far superior to the modeled alternatives. This result proves to be robust over a range of different cases and sensitivity analyses. We also find that the intertemporal rebalancing of the two-part tariff carried out by the Transco so as to expand the network is such that the fixed tariff part turns out to be relatively large compared to extension costs.Electricity, Regulation, Transmission Expansion, Wind Power

How Emission Certificate Allocations Distort Fossil Investments: The German Example

Despite political activities to foster a low-carbon energy transition, Germany currently sees a considerable number of new coal power plants being added to its power mix. There are several possible drivers for this "dash for coal", but it is widely accepted that windfall profits gained through free allocation of ETS certificates play an important role. Yet the quantification of allocation-related investment distortions has been limited to back-of-the envelope calculations and stylized models so far. We close this gap with a numerical model integrating both Germany's particular allocation rules and its specific power generation structure. We find that technology specific new entrant provisions have substantially increased incentives to invest in hard coal plants compared to natural gas at the time of the ETS onset. Expected windfall profits compensated more than half the total capital costs of a hard coal plant. Moreover, a shorter period of free allocations would not have turned investors' favours towards the cleaner natural gas technology because of preexisting economic advantages for coal. In contrast, full auctioning of permits or a single best available technology benchmark would have made natural gas the predominant technology of choice.Emissions trading, Allocation rules, Power markets, Investments

Strom aus der Wüste: keine Fata Morgana

Die Energiepolitik steht vor zwei großen Herausforderungen: Erstens wird fossile Energie in Zukunft immer knapper und teurer, und weltweite Konflikte um Rohstoffe werden weiter zunehmen. Zweitens führt die Verbrennung fossiler Energieträger, insbesondere von Kohle, zu einem Anstieg der Emissionen klimagefährlicher Treibhausgase. Deshalb muss der Anteil erneuerbarer Energien an der Energieversorgung deutlich zunehmen. Sie stehen anders als fossile Energien nahezu unbegrenzt zur Verfügung, und bei ihrer Nutzung entstehen kaum klimagefährliche Treibhausgase. Insbesondere der großflächige Einsatz von Sonnenenergie zur Stromgewinnung hat enorme Potentiale. Theoretisch könnte mit in Nordafrika installierten solarthermischen Kraftwerken auf einer Fläche von ungefähr der Größe Hessens der gesamte europäische Strombedarf gedeckt werden. Voraussetzung für den verlustarmen Import großer Strommengen aus dem Mittelmeerraum ist allerdings der Aufbau von Hochspannungs- Gleichstromleitungen. Ein europäischer Netzausbau könnte auch die Marktintegration heimischer erneuerbarer Energien wie der Windkraft erleichtern und nicht zuletzt den Wettbewerb auf dem Strommarkt verbessern.Electricity trade, Solar energy, DESERTEC