Cross building energy exchange: legal and economic framework and influencing factors (GebEn)

Using an interdisciplinary approach, the legal, technological and economic aspects of the cross-building exchange of heating and power were analysed separately within a metho­dological framework which includes different system configurations relevant to the specific situation in Austria.

Short Description




Starting point/Motivation

The cross-building energy exchange requires a systematic view of individual components of the energy supply system and includes in addition to the energy production technologies also the buildings, where the energy (electricity/heat) is exchanged and also the network infrastructure, which is responsible for the transfer of the exchangeable energy.

As far as exchange of energy beyond the boundaries of a building is concerned, in the past in particular technical concepts had been analysed scientifically and pilot projects had been implemented. Economical and especially legal aspects and influences have been greatly neglected in this context. The project GebEn is going one step further and analyses, non project-based, but from the general legal view and taking into account the relevant economic and technical aspects, possibilities, chances but also new problem areas in connection with the energy exchange across-buildings.

Contents and Objectives

The fundamental goal of the recent study is to develop the legal and economic aspects of the cross-building energy exchange for electricity and heat separately, under consideration of technical relevant restrictions. In addition, based on the legal analyses, an Austrian-wide standard contract for the specific sector (electricity/heat) is created and thus serves as a basic conclusion of the present study.

According to these primary goals the following sub-objectives are :

  • Determination of the analytical framework, to legally and economically evaluate the cross-building energy exchange.
  • Comprehensive analysis of relevant provisions of law as well as the description of legal problem areas.
  • Elaboration of relevant technology and system configurations for electricity and heat.
  • Analysis of the economic framework conditions and economic ratings of the configurations.
  • Implementation of an economic legal evaluation of possible configurations.
  • Development of legal adaptation requirements and a list of criteria for standard contracts.


In a first step, a scope of the investigations is set, which represents the base for the legal and economical investigation of this project. This defined scope contains the following scenarios:

  • The cross-building electricity exchange between a producing building and a customer via private direct lines.
  • The cross-building electricity exchange between a producing building and a customer by using the existing public electricity grid.
  • The cross-building heat exchange between a producing building and one or more customers over private lines.
  • The cross-building heat exchange between a producing building and one or more customers by using the existing public heat grid.

Fist all four variants are analysed separately in detail to their legal effects. Based on this research framework the next step is to provide an economic assessment in the context of individual versions against the background of cross-building energy exchange. The economic analyse takes into account the different energy carriers or production technologies as well as different building types, where the energy exchange of electricity or heat should be undertaken. The respective economic analyses, is distinguished between different cost categories (energy costs, infrastructure costs, etc.) and payment models. Subsequently, economically interesting versions of the cross-building energy exchange are legally detailed presented and explained to finally lead to be able to prepare respective standard contracts for the individual variants of the cross-building energy. The following figure provides an overview of the individual working packages of the project GebEn.

Prospects / Suggestions for future research

In general it can be stated that for a cross-building power change in particular PV systems are suitable, since this technology has been proven for all types of buildings, it has high growth rates and can also be operated economically viable. The statistical analysis of household load profiles in combination with a PV feed-in profile also revealed that the more the two load profiles from each other differ, the higher is the consumption of the households, i.e. the more can be actually used by the PV yield and the less power must be obtained from the public network. Also essential for the effectiveness of PV electricity is the current demand of the two households and size of the installed PV system. The analysis shows that by increasing the size of the system the entire internal consumption increase slightly and is also associated with much higher investments. By analysing the combination with a battery storage system much higher self-consumption shares were quantified, which are associated with much higher total annual cost and specific energy costs. Hence, the cross-building power exchange could be operated economically meaningful in the future depending on the electricity prices, the costs for the battery storage and the distances for the direct line.

Since the supply of neighbours results in relatively high administrative and organizational efforts, appropriate legislative changes would be possible, provided that this is politically desired. Taking into account the requirements under EU law in the context of EltRL 2009 would require in ElWOG 2010 legal clarifications, who may operate and under which conditions a direct line may be installed. It should be taken into account that the mixing with electricity from the public grid in the direct line is not allowed according to the present view in Austria. So the question arise how an electricity company, that produces no power itself, should supply a customer through a direct line. Also it has to be mentioned that the concept of "authorized" customers can be deleted, since now all end users have network access and thus free choice of supplier.

The findings of the economic analysis of the cross-building energy exchanges show that especially the cross-building heat exchange can only be economically viable in certain cases. An economically interesting version can be specifically operated at new buildings, because there the most cost-effective installation for direct lines can be used, the revenues can be maximized due to the low temperature level of the heating systems and only a small distance between the heating systems have to be passed. In this case, however, a supply of allinvolved buildings should be covered by a heating system because the economies of scale as a function of the power of the heating system have the greatest impact to the economic viability.

Project Partners

Project management

Andrea Kollmann - Energieinstitut an der Johannes Kepler Universität Linz

Project or cooperation partners

  • Technische Universität Wien
  • Institut für Energiesysteme und elektrische Anlagen
  • Energy Economics Group
  • Energie AG Oberösterreich

Contact Address

Energieinstitut an der Johannes Kepler Universität Linz
Andrea Kollmann
Altenberger Straße 69
Tel.: +43 (732) 2468-5660
Fax: +43 (732) 2468-5651