Quality of Living and Sustainability Indictors – City of Ljubljana , Vision 20505

The greatest challenge of future development of urban areas has been related with the sustainability issues. Unfortunately, sustainability issues and related costs of resources, including energy, occupy minds only of minority in the society. In the process of transition toward low carbon society many countries have set indicative targets which are revealing desired momentum of change but only at the national level. The absence of clear and direct transformation of national targets into implementation programmes at the local level was the crucial reason why many previous goals have not been achieved. Within the paper, six main sustainability indicators related to the quality of living in urban areas have been described and discussed. Indicators have been tested and customised during the analysis of future development challenges of the Slovenian capital, City of Ljubljana. Results of the analysis show that suggested indicators may be used in the process of municipal energy planning. During the research work, technology and sector oriented bottom up reference energy and environmental system model of City of Ljubljana has been developed. It is the first so complex reference energy and environmental system model that has been developed on the municipal level in the Southeast Europe.


Introduction
During recent decades the world has experienced unprecedented urban growth and according to the United Nations Human Settlements Programme urban areas are responsible for around 75% of the world's energy consumption and for almost 80% of the world's CO 2 emissions.According to (United Nations Population Division, 2008) in 2008, for the first time in history, the world's population was evenly split between urban and rural areas.It is important to emphasise that more developed nations were about 74% urban, while only 44% of residents of less developed countries lived in urban areas.Also, according to (United Nations Population Division, 2008) the urbanization is occurring rapidly in many less developed countries and by 2030, it is expected that cities will house 60% of the world's population -equivalent to the total global population in 1987.
According to European criteria, cities are a basic element of modern societies and states, namely about 80% of European population live in urban areas.Issues related to the sustainable and climate friendly development are posi-tioned very high on the political agenda in the European Union (EU) and have great potential for inter-urban cooperation and knowledge sharing.The local authorities play an essential role in functioning of local energy system, both as the policy makers and as owners of large number of public buildings and infrastructure (Beke-Trivunac & Jovanović, 2013).Local energy solutions are a vital part of the future secure and efficient energy supply on the municipal level and that is the reason why new, tailor-made models for specific local conditions are a necessary premise to achieve set targets.Energy is an essential factor in overall efforts to achieve sustainable development (Vera & Langlois, 2007).Excellent example of research and review of renewable energy strategies for sustainable development and perspectives of converting present energy systems into a 100% renewable energy system can be found in (Lund, 2007) and (Lund & Mathiesen, 2009).According to (Lund, 2007), 100% renewable energy system is possible but large-scale renewable energy implementation plans must include strategies for integrating renewable sources in coherent energy systems influenced by energy savings and energy efficiency measures.Unfortunately, cities often do not have sufficient financial or human resources, by which they could take over a more active role in the improvement of the quality of living.The most frequent mistake in the sustainable urban development is related with the copy-paste planning where peculiarities of own city are ignored and proposed solutions are blind copies of foreign strategies and solutions.Each city is different and has to develop its own strategy for its sustainable and climate friendly development.It has to be emphasised that the cooperation with other cities and exchange of experiences is more than desirable and it has to be stimulated, but concrete solutions have to be based on priorities and peculiarities of each individual city.Excellent example of the method for selecting and calculation indicators of sustainable development, needed for determining the level of sustainable development, expressed through sustainability index of residential buildings can be found in (Vučićević, Jovanović, Afgan, Turanjanin, 2014).This paper presents the overview of the most important targets and challenges for the future development of the City of Ljubljana.Also, within the paper six main sustainability indicators related with the quality of living in urban areas have been described and discussed.Indicators have been tested and customised during the analysis of future development challenges of the Slovenian capital, City of Ljubljana.During the research work, technology and sector oriented bottom up reference energy and environmental system model of City of Ljubljana has been developed.It is the first so complex reference energy and environmental system model that has been developed on the municipal level in the Southeast Europe.

Methodology -energy, environment and sustainability in urban areas
During the last decade several new concepts of energy planning and energy forecasting have emerged, such as decentralized planning, energy conservation through improved technologies, waste recycling, forecasting models, integrated energy planning and introduction of renewable energy sources as presented in (Connolly, Lund, Mathiesen, & Leahy, 2010) and (Weijermars, Taylor, Bahn, Das & Wei, 2012).Nowadays, energy systems have become more complex and application of new statistical and information technology is essential.Transition from traditional methods of energy planning and the use of newly developed methods for integrated resource planning have enabled the tools to research and combine a vast array of often contradict sectorial goals into one structured energy system on a national, regional or municipal level (Avetisyan, Bayless, & Gnuni, 2006) (Ćosić, Krajačić, & Duić, 2012) (Milan, Bojesen, & Nielsen, 2012) (Pusnik, Sucic, Urbancic, & Merse, 2012) (Hamdan, Ghajar, & Chedid, 2012).Development of the electricity smart grids is recognised as an important element in the process of transformation towards new and low carbon energy systems (Blumsack, & Fernandez, 2012).However, electricity smart grids must be coordinated with the utilisation of RES being converted into other forms of carriers than electricity including heat and bio fuels as well as energy conservation and efficiency improvements (Lund, Andersen, Østergaard, Mathiesen, & Connolly, 2012).
Within the research work technology and sector oriented bottom up reference energy and environmental system model of City of Ljubljana (REES-MOL) has been developed.REES-MOL was developed in MESAP environment and it was used for calculation of energy and emission balances together with all related costs for both scenarios.The MESAP standard software is a platform for building customer-specific strategic information systems.The core of MESAP is a powerful database that gathers all the information in a central data pool.The simulation model of MESAP (Modular Energy System and Planning) environment is called PlaNet and consists of two independent modules: a module which balances flows of energy (end-use and supply) and the module for calculating macroeconomic costs linked to selected commodity flows.The MESAP is a linear accounting model with flexible data structure and it can be adapted to the level of aggregation and accommodated to any reasonable level of detail.Scenario-based planning was integrated into the MESAP environment, allowing integration of past, present and planned (calculated) data in a comprehensive overall system.According to (Connolly et al., 2010), MESAP can be used in national or regional energy system modelling and it has no limitations regarding the scenario timeframe or time-step.
Combined with its open structure, this makes MESAP a very suitable model-ling tool for small municipal energy systems where many peculiarities have to be taken into account.MESAP supports a technology-oriented modelling approach where several competitive technologies that supply energy services are represented by parallel processes.The volume of a service supplied by a technology (e.g.heat) is defined by market shares that split the service demand between competitive processes or technologies.Parallel competitive technologies have been included in the model, as presented in Fig. 1.  2010).During the development of the REES-MOL model, trade-off between the simulation and optimisation approach has been done, favouring presentation of relations between controls and their final effects rather than the elusive optimality of results which can be misleading for municipal energy systems.

Sustainability issues in urban areas
Sustainable and climate friendly development of urban infrastructure in a narrower sense means, that the city does not postpone current problems into the future.In a broader sense it means responsible behaviour of all municipal structures, from the city administration to each individual citizen.According to (Birnera & Martinot 2005), this can come through changes in regulation, taxes, subsidies, access to capital and provision of trusted information, as well as marketing and campaigning to raise the awareness and encourage consumers to make choices that are both economically and environmentally acceptable.According to (The Economist Intelligence Unit, 2008), decisions and concrete actions of individual persons have greater power than capability of municipal administration to interfere with their actions.In the framework of sustainable and climate friendly development of urban areas, the most often highlighted problems are efficient spatial planning, efficient and secure energy supply and efficient public transport.Energy efficiency is a red line, which connects all the above mentioned areas.
Transition from environment unfriendly fossil fuelled urban economy to sustainable and climate friendly urban development requires design and formation of policies and solutions, which will be based on excellent knowledge of development alternatives and awareness about new opportunities in exploitation of urban environment as an energy system.Looking long term, in sustainable development of urban areas, renewable energy sources do not have an alternative.For example, in the field of wastes treatment, eastern European capitals are experiencing great changes, former and unsustainable practice of waste disposal has been transformed to ecologically more acceptable ways of waste management.Awareness and susceptibility for new approaches in waste treatment is one of the key factors for the success of programmes of sustainable waste management in the A very important assumption in both scenarios is that comfort of residents, users of services in the urban area remains the same or it even increases with the use of new technologies and change in consumption patterns.Quality of infrastructure, services and living in urban area is one of key factors for strengthening the city competitiveness.

View to 2050 -key findings, results and discussion
Already for some years, Ljubljana is characterised by the continuous improvement of quality of living.The term quality of living is used to evaluate the general well-being of individuals and societies and it is used in a wide range of contexts, including the fields of international development, healthcare and politics (Mercer, 2011).
According to the Scenario -80%, it is possible to significantly improve energy efficiency and reduce CO 2 emissions caused by industry (despite industrial growth) in Ljubljana by the year 2050 in comparison with the reference year 2008, Fig. 3.By the year 2050, final energy consumption in households can be reduced to 1.9 PJ or for 65% in comparison with the reference year.The most important lever for achieving these effects is the increase of energy efficiency in buildings, Fig. 4.

Figure 4. Calculated energy savings in households
Source:Author Analysis has shown that it is possible to considerably reduce losses in Ljubljana water supply system (Fig. 5) with an extensive renovation of distribution pipelines and implementation of modern technologies of pressure and flow regulation.According to the calculations, water loses in Ljubljana water supply system in 2050 will not exceed 5% of all pumped water.

Figure 5. Yearly water consumption [m 3 /inhab] in City of Ljubljana for the period 2000-2050
Source:Author To achieve both scenarios, Ljubljana has already fulfilled an important infrastructure pre-condition, namely well-functioning district heating and cooling system.To ensure additional positive effects in the Scenario -80%, an upgrade of both systems was foreseen, as well as introduction of micro district cooling system.According to the calculated projections, electricity production in City of Ljubljana will increase, especially due to the new hydro power plants on Sava River and in 2050 it will cover almost 60% of Ljubljana electricity needs.In 2050, 69% of electricity produced in Ljubljana will be from renewable energy sources, Fig. 6.   Figure 7. Foreseen investment structure of the energy retrofit programme of public buildings in Ljubljana (Merse, 2012) Source:Author

Sustainability indicators in urban areas
While sustainable development is a common goal for nations, communities, and companies, its quantification remains difficult.Since human activities are closely linked to energy use, the energy system is a good candidate for providing a small, manageable list of interlinked indicators, with the ability to track sustainability.According to (Kemmler & Spreng, 2007), the most important sustainability issues are related to the production and use of energy.Excellent research work with the practical case study on how sustainability indicators can be used for the evaluation of the future development challenges can be found in (Jovanović, Afgan, Radovanović, & Stevanović, 2009).
According to (Kemmler & Spreng, 2007), sustainability indicators can be divided into three main areas: economy, environment and society.Also, there are cases where sustainability indicators are divided into four areas: economy, resources, environment and society (Afgan, Carvalho & Hovanov, 2000).
In the presented research work, the following set of six leading indicators was proposed: -CO 2 emissions in the buildings sector -Environment (CO 2 em), -Share of renewable energy sources in gross final consumption for heating and cooling -Economy/Resources (RES share), -Final energy consumption for heating in domestic buildings per square meter of useful floor area -Economy (FEHpm The first indicator is suitable for monitoring progress toward GHG target.The second indicator is suitable for monitoring progress towards RES target and others toward energy savings target.An important criterion in the definition of indicators was that they could be used for the analysis of the policy and technology driven improvements.

Key findings, results and discussion, Ljubljana -buildings sector
Consumption of the buildings sector (households, services (public and private sector)) in 2008 was 13.1 PJ, which is 45% of the total final energy consumption in the City of Ljubljana.Electricity contributed 31%, district heating 29%, liquid fuels 21%, gaseous fuels 15% and renewable energy sources 3%.
During the definition of both future development scenarios regarding the buildings sector in the City of Ljubljana the following energy efficiency measures were taken into account: -Comprehensive refurbishment of existing buildings, -Optimisation of heating systems, -Purchase of new boilers and heat pumps, -Use of solar systems and heat pumps for water heating, -Low energy or passive standard for new buildings, -Purchase of more efficient household appliances, -Use of more efficient lighting and -Implementation of energy management systems.
Effects of these measures have been evaluated through the proposed set of indicators.According to the calculations, CO 2 emissions related to the buildings sector can be reduced by 81%, the share of renewable energy sources for heating and cooling can be increased from 5% to 67%, intensity of energy use for heating in households can be reduced by 81%, intensity of use of other energy in households can be reduced by 12%, and final energy consumption in services per square meter of useful floor space can be reduced by 49% up to 2050.

Conclusion
Presented research work confirms that the transition from environment unfriendly fossil fuelled economy to sustainable and climate friendly urban development requires new approaches, which must be based on excellent knowledge of alternative possibilities of development and especially awareness about new opportunities in exploitation of urban environment as an energy system.Successful sustainable and climate friendly development strategy of urban areas must be adaptive and must rely on the empirical data.Also, the sustainable transformation of each urban area has to be based on its own strategy, which is developed through the process of learning by own experiences and already executed, successful programmes and projects in a broader environment.The long-term transition towards the low-carbon society requires exploitation of renewable energy sources to a considerably greater extent, and conditions for this must be provided by the comprehensive and adaptive energy policy.
The most obvious result of sustainable urban planning is the continuous improvement of the quality of living, which directly affects attractiveness of the city and consequently enables economic growth of urban areas.With sustainable urban policy it is possible to ensure the optimal living environment, which will be adapted to the needs of citizens.
National goals of sustainable development are determined at the state level, but huge amount of implementation activities are actually going on at the local level and that is why cities need enough manoeuvre space for the efficient execution of sustainable development policies.Unfortunately, it often happens that efforts or measures of different state ministries related to the same urban area contradict each other.Complementation and harmonization of interests between the state, cities and citizens is a necessary precondition for the sustainable development of urban areas.
Presented research work clearly confirms that sustainability indicators can be used for monitoring and measuring the progress of transition toward low carbon society.However, having in mind the recommendations from (Vučićević et al., 2014) additional research work has to be done to investigate if the described approaches can be upgraded.Also, additional research challenges are related with the new trends in urban energy systems modelling.
Finally, it has to be emphasized that even the most advanced energy and environmental polices need informed and motivated citizens who will make energy efficient decisions and sustainably change already established energy consumptions patterns.

Figure 6 .
Figure 6.Structure of electricity produced in City of Ljubljana in 2050, Scenario -80%

Case study -future development challenges of the Slovenian capital, City of Ljubljana Each
(Cerkvenik, Persovsek, & Podboj, 2010)ic, Pusnik, & Bevk, 2011)tage, which is more or less different from others and which has to be considered in the design of the sustainable development strategy.For example, City of Ljubljana is special by its geographic and population smallness, which on one side does not allow the same as to other, larger cities to achieve effects of economy of scale.At the same time, due to the same reason Ljubljana is essentially more flexible regarding the selection of strategy for gaining support of citizens for development projects, connected with the sustainable urban infrastructure and climate friendly development.Estimated annual cost without taxes and duties of final energy consumption in all buildings owned by the City of Ljubljana (museums, theatres, galleries, schools, sport facilities, office buildings, kindergartens, etc. -all together 318 buildings and surface area of 524983 m 2 ) in 2008 amounted to 5.9 million EUR2008, or 1.9% of annual budget of City of Ljubljana(Sucic, Cesen, Stanicic, Merse, Urbancic, Pusnik, & Bevk, 2011).2.Sectoral shares of final energy consumption in Ljubljana in the final energy consumption in Slovenia, reference year 2008 Ljubljana has a significant share in the energy use and CO 2 emissions in Slovenia.In 2008 (the reference year for the study), final energy consumption amounted to 29.0 PJ or 13% of the entire final energy consumption in Slovenia and that is why the transition to the sustainable excellence of the Sloveni-capital cannot be only an issue of the municipality but it is also a national issue.Ljubljana's sectoral shares of final energy consumption in Slovenian final energy consumption are shown in Fig.2.In 2008 the consumption in the transport sector was 10.1 PJ, in services and public sector 6.6 PJ, in households sector 6.5 PJ and in the industry 5.8 PJ.The biggest share was contributed to liquid fuels (46%), electricity contributed 21%, gaseous fuels 16%, district heating also 16% and renewable energy sources only 1%(Cerkvenik, Persovsek, & Podboj, 2010).During the research work two scenarios of sustainable development of City of Ljubljana up to the year 2050 have been developed, namely Reference Scenario and Sustainable Excellence Scenario.Reference Scenario foresees fulfilment of already accepted environmental goals and legislative obligations as well as achievement of at least 50% reduction of CO 2 emissions of City of Ljubljana up to the year 2050 in comparison with the reference year 2008.Scenario Sustainable Excellence is a vision of ambitious transition of City of Ljubljana to the low carbon capital.In the framework of the Sustainable Excellence Scenario (further on Scenario -80%) an 80% reduction of CO 2 emissions is foreseen up to the year 2050 in comparison with the reference year 2008.
transition toward zero-waste society (Wien Energie, 2010)(The Economist Intelligence Unit, 2009).Harmonization of interests between the state, cities and citizens forms a solid base, which is necessary for the development of sustainable urban infrastructure.According to (United Nations Human Settlements Programme, 2011), future challenges of the development of sustainable urban infrastructure in Europe are closely connected with the competitiveness of cities and have to consider trends of population ageing and consequent mobility reduction.3.an Comparison between indicators and national targets shows that target for CO 2 emissions is achievable in the City of Ljubljana taking into account only the buildings sector, where emissions in 2020 were 40% lower than in 2008.The share of renewable energy sources in 2020 in the City of Ljubljana is much lower than the national target, although it increased by 85% compared to 2008.Energy savings target can also be reached since the energy consump-tion in services per square meter decreased by 22% until 2020 and energy consumption for heating in households per square meter decreased by 41%, while other energy use in households per capita remained constant.