The transformation of the energy system is a highly complex process involving many dimensions. Energy system models help to understand the process and to define either target systems or policy measures. Insights derived from the social sciences are not sufficiently represented in energy system models, but address crucial aspects of the transformation process. It is, therefore, necessary to develop approaches to integrate results from social science studies into energy system models. Hence, as a result of an interdisciplinary discourse among energy system modellers, social scientists, psychologists, economists and political scientists, this article explains which aspects should be considered in the models, how the respective results can be collected and which aspects of integration into energy system models are conceivable to provide an overview for other modellers. As a result of the discourse, five facets are examined: Investment behaviour (market acceptance), user behaviour, local acceptance, technology innovation and socio-political acceptance. Finally, an approach is presented that introduces a compound of energy system models (with a focus on the macro and micro-perspective) as well as submodels on technology genesis and socio-political acceptance, which serves to gain a more fundamental knowledge of the transformation process.

Around 25% of final energy consumption in the European Union is currently used for space heating. The potential for reducing this demand through renovation of existing buildings is very significant and recognised to be an important factor for reaching CO2 reduction targets. In this analysis we develop two types of cost curves for heat savings in buildings in 6 European countries. This is based on a detailed representation of the existing building stocks and an analysis and comparison of costs and effects of refurbishment actions for several levels of heat savings in each representative building in these countries. We find that the costs for reaching savings of 40-60% are remarkably cheaper than for reaching higher savings and that the highest and cheapest savings are located in buildings that are still not renovated. We also find the following highly influencing factors on the costs of renovation measures: the share of window area in the envelope, the surface-to-volume ratio and the current heat demand. The results of this work can be further used to investigate cost optimal levels of heat savings versus heat supply in order to draw the right decisions on the way to an efficient and low CO2 energy system. (C) 2020 The Authors. Published by Elsevier B.V.

This paper discusses different decarbonisation scenarios for an existing district heating (DH) network supplied by coal-fired combined heat and power plants in Germany. Integrating higher shares of renewable heat is indispensable in reaching the climate goal and CO2 emission reduction targets. The study analyses the technical and economic aspects of integrating various technologies such as solar thermal, biomass boilers, waste incineration plant and heat pumps into the existing DH network, with the main focus on large-scale heat pumps. The approach consists of two main steps. First, we forecast future heat demand and the potential to extend the DH system by simulating the evolution and energy consumption of the city's building stock. Second, we use a supply dispatch model with hourly resolution to calculate alternative scenarios and sensitivities for the supply mix with a focus on heat pumps. Our results show that, under the current regulatory and economic framework, large-scale heat pumps are not cost competitive with the existing coal-fired CHP units. However, redesigning the regulatory framework and optimising heat pump design and operation could achieve cost parity. The CO2 price induced by the EU emissions trading scheme will most likely not be a sufficient incentive in short and medium term. (C) 2019 Elsevier Ltd. All rights reserved.

District heating (DH) can become a key infrastructure for achieving climate targets in the heating sector. In order to support the uptake of renewables in the DH sector, the European Commission proposed to open DH infrastructures to third parties. This will allow independent heat producers to supply heat produced from renewable energy sources and from waste heat to consumers connected to the grid. This paper develops a better understanding of the complexity associated with the introduction of third party grid access (TPA). We will analyse the heterogeneous institutional set-up of DH markets in the EU and discuss competition and market boundaries in the heat market. Based on this, the paper investigates the technical, regulatory and economic challenges that arise from the practical implementation of TPA. We conclude that TPA alone will not be sufficient to support the expansion of renewables in the DH sector. Complementary policy measures will be necessary to transform the DH sector towards 4th generation DH systems that will become an integrated element of a smart energy system.

In order to achieve long-term targets for energy savings and emission reductions, substantial savings will be needed from existing buildings. For example, a recent analysis for the USA examines aggressive strategies to cut carbon emissions in half by 2040 and finds that in order to achieve this emission reduction target, more than half of existing buildings will need comprehensive energy efficiency retrofits. Germany is targeting an overall primary energy consumption reduction of 50% in 2050 including increasing building renovation rate to 2% per year. In France, ambitious targets have also been set for existing buildings: 50% reduction of primary energy consumption in 2050 compared to the 2012 level. Multiple countries have realized the importance of comprehensive building retrofits and have begun to adopt policies to spur these improvements. For example, Germany is emphasizing grants and loans through the KfW Development Bank, complemented with building and heating system labels, a new “heating check” programme, and possible technical renovation requirements. France has established a goal of bringing all buildings up to “A” performance level (on their A–G scale) by 2050 in order for them to be sold or leased, with lower performance levels required as soon as 2020. In the USA, the focus has been on a combination of rating and disclosure of energy use, financing, and technical assistance. Focused community approaches show promise. This paper summarizes the efforts, successes and challenges, future directions, and savings of building retrofit policies in the three countries. We conclude by contrasting the three countries and discussing areas of opportunity for these and other countries.

Kleinste Losgrößen, viele Bauteilvarianten und ein hoher Anteil manueller Tätigkeiten sind charakteristisch für die Instandhaltungsprozesse in der Luftfahrtbranche. In der vorliegenden Arbeit wird ein Gesamtkonzept zur Automatisierung derartiger Prozesse vorgestellt. Das Konzept greift den Trend in der Automatisierungstechnik nach mehr Flexibilität auf und sieht den Einsatz einer prozessangepassten Automatisierungslösung in Form eines Informations- und Kommunikationssystems auf Prozess­ebene vor. Ein solches ermöglicht die gezielte Unterstützung des Facharbeiters durch die systematische Wiederverwendung von Prozesswissen und die Integration eines Systems zur Fehlervermeidung. Die Anwendung des Konzeptes und seiner einzelnen Lösungskomponenten wird anhand von Teilprozessen der Instandhaltung aufgezeigt.

Kleinste Losgrößen, viele Bauteilvarianten und ein hoher Anteil manueller Tätigkeiten sind charakteristisch für die Instandhaltungsprozesse in der Luftfahrtbranche. In der vorliegenden Arbeit wird ein Gesamtkonzept zur Automatisierung derartiger Prozesse vorgestellt. Das Konzept greift den Trend in der Automatisierungstechnik nach mehr Flexibilität auf und sieht den Einsatz einer prozessangepassten Automatisierungslösung in Form eines Informations- und Kommunikationssystems auf Prozess­ebene vor. Ein solches ermöglicht die gezielte Unterstützung des Facharbeiters durch die systematische Wiederverwendung von Prozesswissen und die Integration eines Systems zur Fehlervermeidung. Die Anwendung des Konzeptes und seiner einzelnen Lösungskomponenten wird anhand von Teilprozessen der Instandhaltung aufgezeigt. ...

The building sector within the EU accounts for about 40% of final energy use and one-third of greenhouse gas emissions. Buildings therefore should play an important role in meeting the EU climate targets. Using the example of Germany, the largest economy of the EU, this paper sets out the methodology for appraising the contribution that comprehensive building renovations, comprising both fabric insulation and heating system upgrades, can make towards decreasing energy use. A dynamic bottom-up simulation model, the Invert/EE-Lab model, evaluates the effects of three scenarios of economic and regulatory incentives for three different renovation packages oriented towards the standards defined by the German building code (EnEv) as well as the support programmes of the KfW development bank. Results are presented visually through Energy Saving Cost Curves which communicate the monetary costs (or savings) and the energy savings for 16 building categories that represent the entirety of the German building stock. The Energy Saving Cost Curves developed in this paper represent the investors’ perspective to 2030. Under the Business As Usual scenario, the total cost effective energy savings potential amounts to 60 TWh/a, avoids 1.1 bn€/a in energy costs, and comprises most of the non-residential building categories and the oldest residential buildings built before 1948. Increasing the level of subsidy in the High Subsidy scenario results in an almost doubling of cost-effective savings to 118 TWh/a while increasing energy cost savings to 1.9 bn€/a. Energy Saving Cost Curves provide a means to compare the impact of different policy options from the perspective of the investor for different building categories, and can thereby feed directly into the design of renovation strategies -whether at national, regional or city levelunder a wide variety of conditions and taking into consideration economic parameters ranging from subsidies and energy prices, to transaction costs, learning curves and discount rates.

The following paper conducts a regional analysis of the U.S. and Chinese buildings' potential for adopting Distributed Energy Resources (DER). The expected economics of DER in 2020-2025 is modeled for a commercial and a multi-family residential building in different climate zones. The optimal building energy economic performance is calculated using the Distributed Energy Resources Customer Adoption Model (DER-CAM) which minimizes building energy costs for a typical reference year of operation. Several DER such as combined heat and power (CHP) units, photovoltaics, and battery storage are considered. The results indicate DER have economic and environmental competitiveness potential, especially for commercial buildings in hot and cold climates of both countries. In the U.S., the average expected energy cost savings in commercial buildings from DER-CAMs suggested investments is 17%, while in Chinese buildings is 12%. The electricity tariffs structure and prices along with the cost of natural gas, represent important factors in determining adoption of DER, more so than climate. High energy pricing spark spreads lead to increased economic attractiveness of DER. The average emissions reduction in commercial buildings is 19% in the U.S. as a result of significant investments in PV, whereas in China, it is 20% and driven by investments in CHP. (C) 2014 Elsevier B.V. All rights reserved.

In the light of the EU directive for renewable energy (2009/28/EC) this paper deals with the question how various policy instruments could impact the development of renewable heating technologies. The paper applies the simulation model Invert/EE-Lab for the building related heat demand in selected European countries (Austria, Lithuania and United Kingdom). The resulting scenarios up to 2030 are compared to RES-Heat targets from literature, stakeholder consultation processes and the targets in the national renewable energy action plans submitted by EU Member States in 2010. The results demonstrate that use obligations for renewable heating can be effective in achieving RES-Heat market growth. However, in order to attain a balanced technology mix and more ambitious targets, policy packages are required combining use obligations with economic incentives and accompanying measures. Technology specific conclusions are derived. Moreover, conclusions indicate that the action plans are not always consistent with policy measures in place or under discussion.

E RNEST O RLANDO L AWRENCE B ERKELEY N ATIONAL L ABORATORY B ERKELEY N ATIONAL L ABORATORY A U.S. and China Regional Analysis of Distributed Energy Resources in Buildings Wei Feng, Goncalo Mendes, Shi Wang, Michael Stadler, Jan Steinbach, Judy Lai, Nan Zhou, Chris Marnay China Energy Group Environmental Energy Technologies Division Lawrence Berkeley National Laboratory June 2013 This work was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Building Technologies Program, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231, U.S.-China Clean Energy Research Center (CERC) -- Building Energy Efficiency, and Energy Foundation China through the U.S. Department of Energy under Contract No. DE-AC02-05CH11231

At present, expanding the use of renewable energy sources for heating (RES-H) relies predominantly on publicly funded support instruments. As these are subject to subsidy cuts and suspensions, these instruments do not provide long-term security for investors and technology suppliers. Although feed-in tariffs and quota-based systems are the major support schemes for renewable energy sources in the electricity sector, similar policy designs have not been applied to RES-H. This paper presents and evaluates three different policy instruments which have the potential to finance RES-H without using public funds: a physical quota system for biomass, a technology-based quota system (Portfolio Model) and a remuneration-based system (Premium model). The assessment suggests that while the Portfolio Model and the Premium Model are both promising policies to enhance RES-H deployment, there is greater acceptance among stakeholders for the Premium Model.