In recent years, many energy scenario studies have proven that a power supply system based on renewable energies (RE) >90 percent is feasible. However, existing scenarios differ significantly in the composition of generation technologies. Some scenarios focus on wind energy in the northern part of Europe, others base on a large utilisation of solar technologies in the south. Apart from the generation capacities, the needed technical flexibilisation strategies such as grid extension, demand flexibilisation and energy storage are generally known and considered in many scenarios. Yet, the impact of different renewable generation strategies on the local utilisation of flexibility options needs to be further assessed. Based upon the BMBF research project RESTORE2050, analyses have been carried out that focus on these interdependencies. The results of the project show that the local utilisation of flexibilisation options depends to a great extent on the technology focus of the long-term renewable expansion strategy. This applies for the spatial flexibilisation as provided by transnational interconnection capacities, especially the ones connecting regions with a surplus of power generation (e.g. GB, Norway and Spain). Another impact of the renewable scenario is seen on the required temporal flexibilisation of electricity generation and demand. In addition, the available options will compete for high utilisation in a future energy system. The differences in the utilisation of these applications, which base on the varying shares of photovoltaic (PV) and wind energy generation, lead to the conclusion that the decision about longterm RE expansion ought to be made very soon in order to avoid inefficient flexibility pathways. Otherwise, if the future RE structure will be kept open, adequate adoption of new flexibility options will be difficult, especially in case of technologies with long lead and realisation time (e.g. new power grids and large scale energy storage devices).
Energy efficiency of a range of domestic appliances covered by the labelling and ecodesign directives has improved significantly over the last 15 years. However, the power consumption of the German residential sector has remained relatively constant over this period. Besides other factors, such as decreasing average household size, the main reasons for this development were the increases of the types, features, size, equipment stock and usage times of appliances and devices in private households.
The project "Energy Sufficiency - strategies and instruments for a technical, systemic and cultural transformation towards sustainable restriction of energy demand in the field of construction and everyday life" investigates how the complementation of energy efficiency with energy sufficiency could lead to more user adequate domestic products and product-service systems and thereby result in an absolute reduction of power consumption.
In this project, energy sufficiency is defined as a strategy to reduce energy consumption by three approaches:
1. Quantitative reduction of sizes, features, usage times of devices etc.
2. Substitution of technical equipment in households by e.g.urban services.
3. Adjustment of technical services delivered by appliances toutility needed and desired by users.
The energy saving effects of an application of these approaches were modelled for different types of households and the energy saving potentials of energy sufficiency quantified. Innovative approaches for user adequate products and services were developed in open innovation workshops by the Design Thinking method. The paper summarizes some of the intermediate results of theoretical and transdisciplinary investigations of the project that runs until May 31, 2016. Furthermore, a first set of design criteria for user adequate appliances enabling energy sufficiency are developed based on these results. The paper concludes with suggestions for the future development of energy labelling and ecodesign derived from the design criteria and supplemented by examples of existing requirements according to the voluntary environmental label "Blauer Engel".
Nachhaltiges Ressourcen-Management : eine Herausforderung für die Politik und die Wissenschaft
(2013)
In the light of the tremendous challenges facing the energy systems of the Middle East and North Africa (MENA), a number of concepts, roadmaps and scenario studies have emerged, describing potential transformation pathways towards a more sustainable, renewable-based, energy supply future in the region. Our article uses the scientific approach of "transition research" to analyze the most pertinent publications and concepts in this field to identify the key drivers and barriers for the transformation of the regional energy systems. The analysis likewise includes an assessment of possible indicators and indexes that can be used to monitor the sustainability of the transformation process of MENA energy systems.
The need of recycling obsolete mobile phones has significantly
increased with the worldwide propagation of mobile phones and
their inherent rapid turnover. In this article, we examine the
acceptance of mobile phone return programs by using the
Technology Acceptance Model and multiple case studies. Our
findings can provide valuable recommendations for the setup of
future mobile phone return programs.
Innovation and diffusion of car-sharing for sustainable consumption and production of urban mobility
(2008)
The Chinese national government has put energy efficiency and pollution control at the heart of its 11th five-year plan (2005-2010). However, implementation of national policies at the local level is notoriously poor in China. In order to tackle this problem, voluntary agreements were signed between local Environmental Protection Bureaus and 14 mostly state-owned companies from different energy-intensive sectors in Nanjing, Xi'an and Kelamayi in the context of an ongoing EU-funded pilot project. In Nanjing, for instance, agreed targets are in the range of a 3-5% reduction in energy intensity by 2009 over a 2007 baseline. The pilot agreements are informed by Dutch experiences with long-term agreements on energy efficiency (LTA/1989-1999) as European best practice, but have been significantly adjusted to Chinese circumstances. Much emphasis was put on process management applying a cooperative approach throughout. Each enterprise put together a so-called Energy Action Team for voluntary agreement development and implementation. This helped to create a sense of ownership in the companies and assigned clear responsibilities. Energy Action Teams conducted Energy Potential Scans in cooperation with a Dutch expert to identify energy saving potentials and possible measures to realize them. On this basis, achievable targets were agreed and a detailed action plan was developed. A first evaluation is scheduled for April 2009. By lifting industry on a more equal power level with government authorities, voluntary agreements showed to be an effective policy instrument to overcome traditional institutional constraints to environmental policy implementation at the local level in China.
Techno-economic feasibility study of solar and wind based irrigation systems in Northern Colombia
(2014)
Water pumping systems powered by solar and wind energy are a clean, decentralized and economic alternative for the irrigation of crops. The intense droughts experienced in the last years in Northern Colombia due to particularly strong Nino Phenomena have reactivated the need of reliable water pumping irrigation systems in that region. This study aims to assess the techno economic feasibility of solar and wind based pumping irrigation system, taking as case study the Municipality of Piojo in the Atlantico department. In the first stage of the study the irrigation water requirements were determined by using the software CROPWAT based on two different crop patterns that represent existing feasible alternatives for small farmers of the region: i) a common crop pattern, which represent the current average distribution of crops for subsistence farming and ii) a fruit cash crop pattern that comprises crops for which well established markets in the region exist. Solar wind and diesel based pumping systems were sized based on the crop water demands for 1 ha. The unit irrigation costs of the three technologies, the two crop patterns and the three irrigation methods (surface, sprinkler and drip) were calculated and compared. The economical analysis was complemented with a cost-benefit analysis over 20 years. Our results show that both renewable energy based pumping systems (wind and solar) can cover the irrigation water demands of small farmers in the region. The economical analysis shows that windmills are the most cost effective solution followed by the solar pumping system. Diesel pumping system was the less cost effective, even though it does not comprise investment in water storage tank. The cost benefit analysis demonstrates that any irrigation system is financially unfeasible when providing water to a common crop pattern. In case of the fruit cash crop scenario the highest dividends were obtained by the wind pumping system and the lowest dividends by the diesel pumping system. The lowest payback period was obtained by the windmill after 7 years and could be even feasible after the fifth year if the surplus water would be used to irrigate larger areas. Dividends obtained in a fruit cash crop scenario with irrigation after 20 years were in the range of EUR 5200 and EUR 11200 higher than dividends obtained by the same crop pattern but without irrigation.
A case study in the rural area of South Westphalia, Germany, showed the importance of independent intermediaries to support the development and implementation of sustainable energy and efficiency projects. The idea behind the project "Dorf ist Energie(klug)" (Village is Energy(smart)) was to foster, accompany, and support energy and efficiency projects in villages from the first idea to final implementation. Therefore, the South Westphalia Agency as independent intermediary initiated an application process in which villages could apply with their innovative energy and efficiency project ideas. During the following process the chosen "coaching villages" benefitted from the consultation of teams of thematic experts. Villages with less developed projects were supported through idea workshops with experts and study visits.
The accompanying scientific study evaluated the overall process focussing on the transferability, the sustainability and the quality of the process. Furthermore, a self evaluation tool for (energy) projects in villages was developed and tested in two of the participating coaching villages.
The paper gives a short insight into the project "Dorf ist Energie(klug)". It presents the methodology of the accompanying study and the results with a special focus on the role of the South Westphalia Agency as independent intermediary. Finally, it discusses the transferability and sustainability of the project.
The efficiency strategy to exploit the potential for energy savings in buildings still is applied rather slowly in most countries. In addition, there are indications that energy savings are partly compensated particularly by wealth but also rebound effects, the "empty nest" (persistence of elderly people and couples in family homes), and cohort effects (e.g. vintages of people or buildings). In Germany, as in other European countries, the existing trend in housing is a continuously growing floor space per capita. Over the last decades it expanded from about 20 m2 in 1960 to currently 45 m2 per person. Forecasts expect a further increase to more than 50 m2 per person. Obviously, more floor space needs more energy for space heating and cooling, ventilation, and lighting, but it also allows the household to operate more and or bigger appliances, all of which increase energy consumption.
On the other hand, housing projects emerge offering relatively small private living spaces in combination with various shared spaces to use. Many of them are based on private initiatives. But what is the motivation behind it? And is there a higher need for new living concepts in the future?
The proposed paper presents main drivers of increasing floor space per capita in Germany and discusses the question if more space is necessary for higher comfort. It presents different examples of housing concepts that strive to achieve good living with less space and suggests a "building typology of sufficiency".
Finally, the paper discusses qualitatively to which extent these housing concepts can lead to less energy use and emissions. In this way sufficiency could be best friend with efficiency and tackle wealth, rebound, and other effects that counter-act efficiency progress. But therefore, as the paper concludes, politics and policies should recognise sufficiency as a field of action instead of referring to individual decisions and lifestyles.
Estimating the sufficiency potential in buildings : the space between underdimensioned and oversized
(2019)
The emission reduction potential of energy efficiency and energy supply in buildings is estimated in various energy and climate action plans, scenarios, and potential analyses. But the third pillar of sustainability - sufficiency - is neglected in most studies.The increasing demand of space per person in the residential sector is a trend in most European countries. Its implication on energy use, demand for resources like land, building material, equipment, and waste production is enormous. Next to the ecological impact, the distribution of space has social and societal effects. Thus, sufficiency policies in the building sector complementing efficiency and energy policy are needed for a sustainable development of the European building stock.
But how can a sufficiency potential in the building sector be estimated? How much space and equipment is needed for a decent living and how much is too much? The paper proposes four areas of sufficiency in buildings: space, design and construction, equipment, and use. It presents a set of indicators, a quantitative estimate of energy savings from reduced per capita floor area, and visualises the sufficiency potential in European countries in an experimental approach. The final discussion focuses on the question: What does this mean for policy making?
The German contribution to limiting global warming to two degrees has to be - as in other developed countries, too - a reduction of 80 to 95 percent of CO2 emissions by 2050 compared to 1990. The project "Low Carbon City Wuppertal 2050" has analysed how such a drastic reduction of CO2 could be achieved on a municipal level in the transportation and residential sector by also working on the land use and material flows dimension. The focus of this paper lies on the space heating in the residential sector.
Wuppertal is a city with about 350,000 inhabitants in the West of Germany. According to the CO2 balance (2007) of the city that was adjusted to the year 2010, the emissions that were caused by space heating in the residential sector remained almost the same since 1990. They decreased slightly from 693,000 tons CO2 in 1990 to 691,000 tons in 2010, although final energy use for space heating increased by about 15 percent. But the shift of energy sources especially from coal to gas avoided an increase of emissions. However, the reduction target of 95 percent means that CO2 emissions have to be reduced to 35,000 tons per year until 2050.
A reference scenario shows that the city could achieve about 30 percent of the reduction required with the current trend of renewable energy development and energy efficiency measures such as retrofitting the building stock. But looking at the difficult financial conditions of the municipality as well as at the socio-economic situation of the inhabitants it becomes clear that the remaining 65 percent of the target to a 95 percent reduction will be difficult to reach and that innovative measures of energy efficiency and sufficiency1 need to be developed.
But which social-ecological effects does the implementation of comprehensive climate protection measures have on the inhabitants of a city? How do people live in a "Low Carbon City"? In this paper qualitative and quantitative scenarios will be developed since the combination of both is promising to show both effects: what share could renewable energies, energy efficiency and sufficiency measures have in reaching the target of 95 percent, and how could life look like in an almost CO2 free city in Germany in 2050.
The concept of regime and "flat ontologies" : empirical potential and methodological implications
(2012)
Die Wärmewende ist als Teil der Energiewende ein gesellschaftliches Großprojekt. Für eine erfolgreiche Umsetzung benötigt die Wärmewende im Vergleich zur Stromwende vielfältigere und differenziertere Handlungsmechanismen. Es geht dabei nicht nur um den Ersatz fossiler Energieträger im Bereich der Wärmeversorgung durch regenerative Quellen, sondern vielmehr um einen systemischen Ansatz, der zudem eine stringente Forcierung von Energieeffizienzmaßnahmen, eine optimierte Verzahnung von Strom- und Wärmesystemen sowie eine zielgruppenspezifische Adressierung und Sensibilisierung von Akteursgruppen (hier: Kommunen, Privathaushalte, Industrie, GHD) erforderlich macht.
About 2 % of the overall electricity consumption of the EU is caused by circulators in single or double family homes and flats. A new technology of pumps with electronically commutated (EC) motor pumps is available now; it is one possible way to achieve a reduction in circulator annual electricity use by 60 % or more.
The project's objective is a market transformation towards this new very energy-efficient pump technologies - Energy+ pumps - for circulators in heating systems, both stand alone and integrated in boilers. Only few manufacturers have so far introduced the new pump technology to the market for single or double family homes and flats.
To bring more products to the market from all major manufacturers, the project will adapt and apply the technology procurement methodology as it was very successfully tested in the European Energy+ project on energy-efficient cold appliances.
Large buyers will be aggregated, to activate the pump and boiler manufacturers. Sales and training materials and a sizing spreadsheet software for installation contractors will be developed and applied. A competition both for energy-efficient products and marketing campaigns will be organised and the information on the Energy+ pumps will be disseminated widely through website, newsletter, media, and fairs.
This paper gives a short overview of this project and presents the results of the first project phases: a European wide market study on circulators and heating systems, and the first Energy+ lists for circulators, buyers and supporters.
Refrigerators and freezers (subsumed under the term "cold appliances") are among the most widely used electrical appliances in the residential sector all around the world. Currently, about 1.4 billion domestic cold appliances worldwide use about 650 TWh electricity, which is 1.2 times Germany’s total electricity consumption, and cause CO2 emissions of 450 million tons of CO2eq.
Although the specific electricity consumption per volume of cold appliances has decreased during recent years due to technical progress and policy instruments like labelling and eco-design requirements, total worldwide energy consumption of these appliances is on the increase. Scenario calculations were carried out for 10 world regions by the Wuppertal Institute. Results show that about half of the energy consumption could be saved with the most energy-efficient appliances available today, and even higher savings will be possible with next generation technologies by 2030. According to the analysis, these savings are usually very cost-effective.
All these aspects are part of the new website "bigEE.net - Your guide to energy efficiency in buildings" which aims to provide information about technical options but also about policies to support the development of energy-efficient appliances.
To initiate and foster market transformation of energy-efficient appliances it is highly advisable for policymakers to generate appliances-specific policy packages. Since each regional market has its specificity (e.g. energy prices, typical appliance affecting the cost effectiveness of efficient appliances), the barriers for the market transformation of single product groups are also specific and need to be addressed by appropriate policies and measures. Elements of measures to build appropriate specific policy packages for refrigerators will be presented in the paper, and the refrigerator package from California (USA) demonstrates the successful implementation of a sector-specific package.
In addition to the expansion of renewable energies, the efficient use of energy is crucial in order to ensure energy transition successful. The Federal Government of Germany has therefore set itself clear objectives with the National Energy Efficiency Action Plan (NAPE), which aims to reduce the primary energy consumption in Germany - compared to 2008 levels - by 20 per cent until 2020, and by 50 per cent until 2050. In addition, greenhouse gas emissions should fall by 40 per cent compared to 1990.
To reach this goal, the German Federal Ministry of Economic Affairs and Energy (BMWi) inter alia launched the "National Top Runner Initiative (NTRI)" in January 2016. It is an important component and concerns private homes, as well as industry, retail and services.
The NTRI is intended to bring energy efficient and high-quality appliances (so called Top Runners) onto the market more quickly, thus accelerate market replacement. For this purpose, motivation, knowledge and competence in product-related energy efficiency is to be strengthened and expanded along the whole value chain - from the appliance manufacturer to the retailer and the consumer. Manufacturers are pushed to develop more efficient products and consumers get valuable information about Top-Runner products and how they can benefit. In this context, retailers are especially relevant as they act as "gatekeeper" between manufacturers and consumers. They play a key role in advancing an energy efficient production and consumption. They do not only select the products but they also have a direct contact to consumers and influence the purchase decision. In this paper, special emphasis will be put on the role of retailers and the efforts of the National Top Runner Initiative will be illustrated. Barriers and incentives to motivate this target group will be elaborated.
The overall objective of the web-based consumer information tool Euro-Topten is to promote the market transformation towards energy efficient products. Euro-Topten informs consumers about the most energy efficient products in various categories and thereby aims to directly influence the purchasing decisions of individuals or professional buyers.
Providers of internet-based information tools are confronted with the problem, that there is no bidirectional interaction with the users. Hence, it is difficult to evaluate if the specific needs of users are addressed, if and how the user processes this information and to what extent the information influences the user's decision making process.
To study these questions, a web-based survey was conducted in two consecutive rounds. In the first round the survey focused on the assessment of the information tool itself and the motivation for using the Euro-Topten websites. This survey was online on all active Euro-Topten partner websites from October to December 2012. In total, 1791 users completed the survey.
In the second round, a subset of the survey population was queried again. 1,043 participants agreed to take part in a more comprehensive follow up survey, 383 completed the second survey between May and July 2013. The second survey concentrated on the question how Euro-Topten has influenced the purchasing behaviour of the survey participants. This gave significant insights on how the information on the Euro-Topten websites has affected purchasing decisions of the surveyed users.
Based on a comparison of performance indicators of the most efficient products recommended on the Euro-Topten websites with performance indicators of a base case product available on the market, avoided energy demand could be estimated for those users, who bought products from the Euro-Topten list. Based on these results, two impacts of Euro-Topten could be estimated: The influence of Euro-Topten on purchasing decision of users and the associated reductions in energy demand and CO2-emissions.