Scholarly article on topic 'The first indications of the effects of the new legislation concerning the energy performance of buildings on renewable energy applications in buildings in Greece'

The first indications of the effects of the new legislation concerning the energy performance of buildings on renewable energy applications in buildings in Greece Academic research paper on "Economics and business"

CC BY-NC-ND
0
0
Share paper
Keywords
{Buildings / "Building energy performance" / "Greek buildings" / "Renewable energy systems"}

Abstract of research paper on Economics and business, author of scientific article — Nikos Papamanolis

Abstract Greece is a country rich in renewable energy sources yet also a country in which the building sector is relatively energy-intensive. In October 2010 the EU Directive on the Energy Performance of Buildings was incorporated into Greek law. At the same time other legislative and administrative measures, as well as financial incentives, were implemented to improve the energy performance of buildings in Greece. Some of these measures were intended to increase the number of renewable energy applications in buildings and to improve the ways in which the country’s favourable climatic conditions are exploited. This package of measures and regulations has had a catalytic effect on the whole of the country’s building production and management system. Based on the first indications of the effects of the implementation of the new legislation, this study attempts to evaluate the impact that the latter has had on the progress of renewable energy applications in buildings in Greece.

Academic research paper on topic "The first indications of the effects of the new legislation concerning the energy performance of buildings on renewable energy applications in buildings in Greece"

International Journal of Sustainable Built Environment (2015) xxx, xxx-xxx

HOSTED BY

Gulf Organisation for Research and Development International Journal of Sustainable Built Environment

ELSEVIER

ScienceDirect www.sciencedirect.com

Original Article/Research

The first indications of the effects of the new legislation concerning the energy performance of buildings on renewable energy applications

in buildings in Greece

Nikos Papamanolis

School of Architectural Engineering, Technical University of Crete, K4 Building, University Campus, 73100 Chania, Greece

Received 27 April 2014; accepted 16 June 2015

10 Abstract

11 Greece is a country rich in renewable energy sources and, at the same time, a country in which the building sector is relatively

12 energy-intensive. In October 2010 the EU Directive on the Energy Performance of Buildings was incorporated into Greek law. At

13 the same time other legislative and administrative measures, as well as financial incentives, were implemented to improve the energy per-

14 formance of buildings in Greece. Some of these measures were intended to increase the number of renewable energy applications in build-

15 ings and to improve the ways in which the country's favourable climatic conditions are exploited. This package of measures and

16 regulations has had a catalytic effect on the whole of the country's building production and management system. Based on the first indi-

17 cations of the effects of the implementation of the new legislation, this study attempts to evaluate the impact that the latter has had on the

18 progress of renewable energy applications in buildings in Greece.

19 © 2015 The Gulf Organisation for Research and Development. Production and hosting by Elsevier B.V. All rights reserved.

21 Keywords: Buildings; Building energy performance; Greek buildings; Renewable energy systems; Solar energy systems; Ground source heat pumps

23 1. Introduction

24 In Greece, the country's geophysical features and

25 diverse climatic conditions satisfy the preconditions for

26 all renewable energy applications. Its geographical position

27 (latitude 38° N) guarantees extended periods of sunshine

28 and high rates of solar radiation, offering great potential

29 for the utilisation of solar energy. Additionally, the coexis-

30 tence of mainland and island land masses creates natural

31 paths for the movement of large air masses, forming a

E-mail address: npapama@arch.tuc.gr Peer review under responsibility of The Gulf Organisation for Research and Development.

remarkable potential for wind energy, mainly over coastal 32

areas. Finally, the widespread presence of numerous small 33

rivers as a result of the country's mountainous topography 34

allows exploitation of hydro energy sources. 35

In this favourable framework, the share of renewable 36

energy sources (RES) in the national energy balance is 37

approximately 26.7%, at the level of total domestic produc- 38

tion of primary energy (Eurostat, 2015a). The primary pro- 39

duction of renewable energies increased from 64,401 TJ in 40

2003 to 104,112 TJ in 2013 (i.e. an increase of approx. 41

61.7%), where biomass accounted for the largest propor- 42

tion (43.1%) followed by hydropower (21.9%), solar energy 43

(20.1%), wind energy (14.3%) and geothermal energy 44

http://dx.doi.org/10.1016/j.ijsbe.2015.06.001

2212-6090/© 2015 The Gulf Organisation for Research and Development. Production and hosting by Elsevier B.V. All rights reserved.

IJSBE 82 ARTICLE IN PRESS No. of Pages 9

25 June 2015

2 N. Papamanolis / International Journal of Sustainable Built Environment xxx (2015) xxx-xxx

(0.5%) (Eurostat, 2015b). In 2013, the last year for which statistics are available, the total amount of generated hydropower, wind and photovoltaic energy in Greece was used for electricity production. The remaining finally consumed energy generated by renewables and waste accounted for 52,236 TJ. Approximately 78.1% of this amount (i.e. 40,774 TJ) was directed to the building sector, with biomass representing the largest percentage of this total (32,744 TJ), followed by solar thermal energy (7788 TJ) and geothermal energy (242 TJ). RES in Greece account for 18.6% of the final energy consumption in the building sector, while the corresponding percentage in the EU countries as a whole is 10.4%. At the same time, the Greek building sector appears to be rather energy-intensive since in 2013 it consumed 36.4% of the total energy consumptions in the country (Eurostat, 2015a).

In October 2010, Greece, in accordance with European legislation, adopted a number of provisions which mainly addressed the issue of energy efficiency in buildings. Apart from that, a number of national programmes were implemented whose primary aim was to promote energy efficiency through the use of RES in public or private buildings but which also provided funding for RD & D activities (Papamanolis and Mandalaki, 2011). At about the same time Greece entered a deep economic recession that had a negative impact on almost all sectors of the economy and on the building construction sector in particular. It is characteristic that, according to data provided by Hellenic Statistical Authority, the volume of new buildings fell from 102.2 million m3 in 2005, the year in which the greatest amount of building activity took place, to 12.2 million m3 in 2013, i.e. it registered an 88.0% decrease in five years. This sharp decline also continued in 2014, since, the total amount of building activity in 2014 registered a 18.3% decrease in the number of new building licences issued, a 14.8% decrease in surface area and a 8.9% decrease in the volume of new buildings, in comparison with 2013 (ELSTAT, 2015).

These facts have had a considerable impact on the whole of the building production and management system in Greece, with the result that the design, construction and exploitation of buildings are now markedly different to what they were a few years ago. From the wide range of consequences that the new legislation on the energy performance of buildings and the circumstances that have prevailed in the country during the last few years has had in Greece, this study attempts to single out and examine those that relate to renewable energy applications in buildings. Given that these applications acquire greater value in countries with rich sources of renewable energy like Greece, the study, on the basis of the first indications of the effects of the implementation of the measures mentioned above, attempts to determine whether these measures are in the right direction and to highlight ways in which they might be improved.

2. The new legislative framework for decreasing energy consumption in buildings in Greece

Greece incorporated the EU Directive 2002/91/EC on the Energy Performance of Buildings (European Parliament and Council, 2003), with the Law 3661/2008, "Directions for reducing energy consumption in buildings and other regulations" (Hellenic Gov., 2008). For its implementation, the Joint Ministerial Decision D6/B/5825/2010, "Endorsement of Energy Performance Buildings Regulation" has been published on April 2010 and it is active since the 1st of October 2010 (Hellenic Gov., 2010).

With the publication of the "Energy Performance Buildings Regulation" (abbreviated from its initial letters in Greek as KENAK), sustainable design and construction has been typically introduced in Greece. This has been done in order to improve all buildings' energy efficiency, their energy savings and to protect and preserve the natural environment. The principal provisions of this legislative framework determine:

- the calculation methodology for the energy performance of buildings;

- the content of building energy performance studies;

- specifications for sustainable architectural design and the thermal properties of the structural elements in the building envelope;

- the minimum energy performance requirements and the classification of buildings according to their energy performance;

- the energy inspection procedure;

- the format and content of building energy performance certificates.

The energy performance study for new buildings and the inspection of energy efficiency in existing buildings are based on a specific methodology consisting of two main steps:

(a) The implementation of required standards for the building under examination in terms of its design, the thermophysical characteristics of its envelope and the technical characteristics of its systems (heating, cooling, ventilation, hot water, lighting and combinations of these).

(b) The comparison of the building under examination with a reference building, i.e. a model building with the same geometrical characteristics, the same site position and orientation, and the same use and operating characteristics as the building under examination. The reference building fulfils the minimum energy requirements and has specific technical characteristics and systems that meet certain specifications laid down by the legislation. An indication of the energy performance of the building under examination is the ratio of its total primary energy

N. Papamanolis / International Journal of Sustainable Built Environment xxx (2015) xxx-xxx 3

154 consumption to the corresponding consumption of This particular legislative framework replaced the earlier 176

155 the reference building. This ratio, in accordance with one of 1979 concerning the energy and environmental per- 177

156 the climatic zone to which the building belongs formance of buildings, which was primarily based on a 178

157 (Fig. 1), places the building under examination in study of thermal insulation and its compliance with rele- 179

158 one out of nine energy performance categories (from vant directives of a rather general nature (Hellenic Gov., 180

159 A+, the highest, to H, the lowest). 1979). 181

160 In February 2013, EU Directive 2010/31/EU, was incor- 182

161 The energy performance category, together with data on porated into the Greek national law (European Parliament 183

162 the energy consumptions of the building to which it relates, and Council, 2010). This new directive revises and 184

163 are stated in the building energy performance certificate. improves the previous one on building energy performance 185

164 The results of the report of the energy efficiency inspector by clarifying and simplifying certain provisions, extending 186

165 are also included in the information recorded on the build- the scope of the directive, making some provisions more 187

166 ing energy performance certificate together with recom- effective and providing for the leading role of the public 188

167 mendations for improvements in the energy efficiency of sector. Moreover, the new European directive requires 189

168 the building concerned, and these are stated in such a member states to ensure that by 2020 all new buildings 190

169 way that users can compare and assess the energy con- are so-called 'nearly zero-energy buildings'. 191

170 sumption of their building and recognise any opportunities Since the beginning of 2011 the new legislation has been 192

171 for improving its energy efficiency. The Certificate is combined with a package of actions which, through a series 193

172 mandatory for all new buildings or buildings that are being of measures and incentives, have aimed to improve the 194

173 renovated. It is also necessary for buildings that are about energy performance of buildings in the country and to sup- 195

174 to be rented or sold and for all public buildings. The port the effort to achieve a 20% energy saving by 2020, as 196

175 Certificate is valid for ten years. measured against the indicative trajectory defined in 197

Fig. 1. Climatic zones in Greece, according to KENAK.

IJSBE 82 ARTICLE IN PRESS No. of Pages 9

25 June 2015

4 N. Papamanolis / International Journal of Sustainable Built Environment xxx (2015) xxx-xxx

Annex I Part B of EU Directive 2009/28/EC (European Parliament and Council, 2009). Among these actions, the "Energy Efficiency of Household Buildings" programme includes a set of financial incentives for the implementation of energy-efficiency upgrading interventions in residential buildings through (a) replacement of doors/windows (frames/glazing) and installation of shading systems; (b) installation of heat insulation on the building shell, including the terrace/roof and open-sided ground-floor parking area, and (c) upgrading of the heating and hot water supply systems (HME, 2010). By the end of 2013 over 40,000 households had been placed under the programme at a total funding cost of over €400 million (HME, 2013). Also, within the same framework, it is worth mentioning (1) the programme "Building the Future (2011-2020)", which aims at reducing the total building energy consumption and increasing the level of environmental protection by using financial instruments and market mechanisms, such as Energy Performance Contracts, Industrial and Commercial Voluntary Agreements, Energy Service Companies and White Certificates (HME, 2012) and (2) the programme "Green Tourism", which provides subsidies for energy efficiency and environmental protection and awareness for investments in buildings in the tourist sector (hotels, accommodation units and complexes) (HMCS, 2010).

Under these arrangements, a strong endowment is being provided to apply renewable sources and exploit the climatic conditions in buildings. The contribution of these arrangements is both direct, through the specific requirements they introduce (e.g. the obligation that passive solar systems, as well as heating/cooling/electricity production systems utilising RES and Combined Heat and Power, must be incorporated in the heating/cooling specification study submitted in the building licensing procedure), and indirect, through the increased standards for energy performance that they prescribe and the recommendations that are being provided for improving the energy performance of audited buildings (Papamanolis and Tsitoura, 2013).

By January 2014, three years after the institution had first come into force, about 509,000 buildings had been tested through the energy inspection system. Of these, a small percentage - just 1.6% (or 8309 buildings) - consists of newly-constructed buildings for which energy studies have been carried out in accordance with the new legislation (HME, 2014). Consequently, the vast majority of the

buildings have been designed and constructed in accordance with older specifications. The inspections that have so far been carried out on such buildings have shown them to have low energy performance levels (Table 1). To be more specific, over one quarter of the buildings that have been inspected have been found to belong to the worst energy performance category (i.e. Category H), while the proportion of buildings constructed before 1980 that are in this category is nearly 40%.

3. Renewable energy in the building sector in Greece during the period 2003-2013

The bar chart in Fig. 2 shows the fluctuating shares of each renewable energy source in the final energy consumption of the Greek building sector during the decade 20032013 (Eurostat, 2015b). The chart includes the amounts of electrical energy generated by rooftop solar photo-voltaics since the latter represent an application in buildings where, in the majority of cases, the electrical energy is also directly consumed by the buildings themselves. In addition, the geothermal energy category also includes the output of the ground source heat pumps, which, as systems that transfer heat to or from the ground, directly contribute to fulfilling the heating or cooling needs of the buildings in which they are installed (Andritsos et al., 2015).

Of the four forms of RES that appear in this chart, biomass and solar thermal could be considered as traditional since they have contributed to the energy consumptions of buildings in Greece for several decades. The other two - i.e. geothermal and solar photovoltaic - are the most recent energy forms, with data on their shares of the energy consumptions of buildings having been recorded only since 2004.

The total share of the above RES in the energy balance of buildings in Greece increased from 33,654 TJ in 2003 to 45,950 TJ in 2013 (i.e. an increase of 36.5%), while each individual form of RES also displayed an upward tendency over the same period. More specifically, of the traditional forms of RES, biomass increased from 29,535 TJ in 2003 to 35,455 TJ in 2013 (i.e. an increase of 20.0%) and solar thermal energy increased from 4119 TJ in 2003 to 7778 TJ in 2013 (i.e. an increase of 88.8%). Biomass clearly has the largest share in the consumption of renewable energy in buildings in Greece. Solar thermal energy comes

Table 1

The average consumptions of buildings inspected under the new legislative framework for the energy performance of buildings in Greece's four climatic zones (kWh/m2/yr) (HME, 2014).

Climatic Detached Multi-storey apartment Offices Shops Elementary school Secondary school Hospitals

zone houses buildings buildings buildings

A 266.44 194.92 314.41 419.76 181.94 141.20 1555.90

B 335.74 219.45 334.46 425.36 184.23 189.21 1059.08

C 449.50 288.27 332.36 428.22 235.43 216.38 736.36

D 488.62 325.80 336.52 463.49 317.09 270.30 -

IJSBE 82 ARTICLE IN PRESS No. of Pages 9

25 June 2015

N. Papamanolis / International Journal of Sustainable Built Environment xxx (2015) xxx-xxx

250 MW

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 □ Biomass DGeothermal □ Solar thermal □ Solar pv

Fig. 2. Evolution of the annual final energy consumption from renewable sources in the building sector in Greece in the period 2003-2013.

second throughout the decade. The last two positions in the listing are occupied by the most recent forms of RES, with solar pv registering a large increase in the last two years of the decade (2012 and 2013) and clearly overtaking geother-mal energy.

The overall upward tendency of renewable energy applications over the decade 2003-2013 displays two peaks. The first peak occurred in 2007 and was followed by a decline until 2009, which marked the beginning of another steady increase until 2012. 2012 was the year that recorded the highest final energy consumption from RES in the building sector in Greece (50,766 TJ), while the following year (2013) registered a 9.5% decrease (45,950 TJ). Any investigation of the factors that brought about this fluctuation would do well to focus on each form of RES separately.

3.1. Solar energy applications

The application of solar systems in Greece began in the mid-1970s with solar water heaters (EBHE - the Greek Solar Industry Association - was created in 1978). Since then, the production of solar water heaters has increased continuously up until 2008, when 300,000 m2 of glazed solar collectors were produced. Following a decrease in 2009 (with 206,000 m2 of new collectors), the market, since then, has been growing steadily until 2012 when solar collector production reached 243,000 m2 in terms of total collector area. In 2013, solar collector production reached 227,150 m2 in terms of total collector area (226,700 m2 flat plate type and 450 m2 vacuum type) or 159 MWth thermal capacity, achieving a decrease of 6.5% over the previous year (ESTIF, 2014) (Fig. 3).

In 2013, Greece, with a total installed solar collector surface area of 4,178,350 m2 or 2925 MWth cumulative installed capacity in operation, ranks second after Germany in the relative rankings of the EU countries, and third, after Cyprus and Austria, in terms of the per capita installed solar thermal capacity (264.4 kWth per 1000 capita) (ESTIF, 2014). On the basis of these figures, Greece holds a significant percentage of the total solar thermal capacity in operation in the EU (9.9%). Hellenic

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

Fig. 3. Evolution in the total annual installed power of solar systems in Greek buildings in the period 2003-2013. Units represent Solar Thermal Capacity (MWth) in the case of solar collectors and Nominal Power (MWp) in the case of photovoltaics.

Statistical Authority research showed that 37. 6% of households in the country have a solar water heater (ELSTAT, 2013). Solar water heating systems for domestic use are typically small units of the closed-circuit type, with an average collector surface of 2.3-2.5 m2 and a storage tank capacity of 100-200 l, which serves the hot water needs for showers, laundry, washing etc. of a single family (Balaras et al., 2013). A considerable proportion of them (approx. 30%) is equipped with an additional heat exchanger connected with the fuel or gas central heating system, which is the most common type of heating system in Greek buildings (Giakoumi, 2009). A typical solar water heater for domestic use in Greece produces 8401.080 kWh/yr. These systems are fitted onto the terraces of buildings, even multi-storey apartment buildings, by means of metal supporting structures, which ensure the proper inclination and orientation of the collector. In rare cases such metal supporting structures may be found adapted to sloping roofs. Even more rarely, solar collectors may be found integrated into the aesthetic of a building or installed at a distance from the building (Papamanolis, 2015).

In the last few years, the considerable drop in the construction of new buildings in Greece as a result of the economic crisis has had a negative impact on the solar thermal collector market. At the same time, however, there has been a swing in favour of the installation of new solar thermal collectors to replace electric and oil heating systems, as a more economical solution.

The growth rate of photovoltaic systems in Greece remained low until 2009. In that year, according to the Hellenic Association of Photovoltaic Companies, the total installed power amounted to 46.1 MWp (HELAPCO, 2014a). Since then, however, the growth rate has increased significantly. In 2013, the installation of new photovoltaics reached 1043 MWp and the cumulative capacity reached 2579 MWp, thus surpassing the national target set for 2020, seven years earlier than projected (European Parliament and Council, 2009). As a result of this increase, in 2013, Greece, with 229 Wp/habitat of installed

IJSBE 82 ARTICLE IN PRESS No. of Pages 9

25 June 2015

N. Papamanolis / International Journal of Sustainable Built Environment xxx (2015) xxx-xxx

photovoltaic power, came to rank 4th among the EU countries, behind Germany (436 Wp/habitat), Italy (294 Wp/habitat), and Belgium (268 Wp/habitat) (EPIA, 2014). In that year the amount of electrical energy generated by photovoltaic systems reached 12.3 PJ, accounting for 6.73% of the total amount of electrical energy produced in the country (HOEM, 2014). Of the total installed photovoltaic power in the country, 14.5% (i.e. 372.7 MWp) corresponds to systems smaller than 10 kWp installed on the roofs of residential buildings or the office buildings of small enterprises. The number of new rooftop photovoltaic systems installed in 2013 amounted to an equivalent of 74.9 MWp, registering a significant slowdown in their annual growth rate. It is characteristic that the corresponding totals for 2012 and 2011 were 195.4 MWp and 95.0 MWp, respectively (HELAPCO, 2014a) (Fig. 3). This development is, in a way, a result of the significant increase that occurred in previous years. The generous incentives that were introduced by the State in 2009 for residential applications (Karteris and Papadopoulos, 2012), have had a greater impact than expected. Consequently, relevant measures have been weakened. The incentives for investing in photovoltaic systems, mainly through feed-in tariffs, have diminished to the extent that such investment is now considered to be unprofitable. It is characteristic that the tariffs for new installations of rooftop systems fell from 550 €/MWh in 2009 (the highest in Europe at that time) to 120 €/MWh in July 2014 (HELAPCO, 2014b). Indeed, in the summer of 2012 the relevant authority imposed restrictions on the number of new licences granted for photovoltaic systems in buildings. In November 2013, with Law 4203 net-metering was established in Greece, i.e. the offset of the in situ generated and consumed electricity by RES (Hellenic Gov., 2013). Although this measure raised hopes of a revival in Greece's photovoltaic market, so far there does not appear to be any evidence that this has happened (HELAPCO, 2015).

In Greek buildings, photovoltaic panels are found almost exclusively on terrace roofs, installed in rows on metal frames, facing south and inclined at an angle of 25-30°, depending on the latitude. They occur mainly on detached houses and small apartment buildings, where

the terrace roof is large enough to cover the needs of the residents (Fig. 4). The majority of the photovoltaic panels constitute new installations on existing buildings, and have been installed with the aim of reducing the energy costs of the buildings they stand on. On multi-storey apartment buildings the installation of such panels is difficult owing to the generally small size of the terrace roofs and, above all, to the proprietary and administrative problems that arise. Furthermore, problems arise from the shadings of the neighbouring buildings, especially if they are higher than the building in which the installation is made, as well as by constructions and installations on the same rooftop, like, the raise of the staircase and the elevator shaft, parapets, chimneys, ventilation ducts etc. (Loulas et al., 2012).

3.2. Geothermal energy applications

Despite the high available potential, applications of geothermal energy in Greece are limited. The installed capacity of direct uses at the end of 2013 is estimated at about 220 MWth, showing a significant increase over the last few years which, however, is almost exclusively attributed to the growth of the ground source heat pump sector. Currently, no geothermal electricity is produced in Greece, despite the fact that a pilot 2 MWe power plant was built and operated for about two years in the 1980s on Milos Island (Mendrinos et al., 2010). The applications for the direct exploitation of geothermal fields in Greece are primarily related to agriculture (greenhouse heating, agricultural drying, fish farming) and concern low-enthalpy sources (Lambrakis et al., 2014). Applications for the direct exploitation of geothermal fields to serve the needs of the building sector were officially recorded for the first time in 2004, and since then have remained rather static with annual energy use in the order of 250 TJ. On the other hand, although ground source heat pump applications began in the late 1990s, their broader use also started in 2004, since when they have registered a remarkable increase (Fig. 5).

Fig. 4. Photograph showing an array of 15 kWp photovoltaic panels (and two solar thermal collectors) on the terrace roof of a building in Attica.

IJSBE 82 ARTICLE IN PRESS No. of Pages 9

25 June 2015

N. Papamanolis / International Journal of Sustainable Built Environment xxx (2015) xxx-xxx

446 At the end of 2014, the installed capacity of geothermal

447 direct heat uses in the Greek building sector is approxi-

448 mately estimated to be 179.7 MWth and the annual energy

449 use is estimated as 925.8 TJ (Andritsos et al., 2015). Of this

450 amount, the greatest proportion, approx. 70.0% (or

451 648.0 TJ/yr), corresponds to ground source heat pumps

452 (GSHP). Approximately 28.1% (or 240.0 TJ/yr) corre-

453 sponds to the direct use of geothermal energy in balneology

454 and pool heating applications, while the rest, only 1.9% (or

455 17.8 TJ/yr), corresponds to individual space heating

456 applications.

457 The use of low-enthalpy geothermal waters for space

458 heating is practiced only in a few cases, which include

459 two spa buildings (one at Traianopolis, in Thrace, with a

460 floor area of 1500 m2, and the other at Nea Apollonia, near

461 Thessaloniki, with a floor area of over 4000 m ), one hotel

462 on the island of Milos (which, however, is closed in the

463 winter), several individual houses in Macedonia and

464 Thrace and one small school building in Thrace. It is also

465 worth noting that the first pilot district heating scheme in

466 Greece (the "Thermopolis" project) has been completed

467 at Polichnitos on Lesvos, although it is currently out of

468 operation due to the failure of the submergible pump.

469 This system will provide heating to five public and munic-

470 ipal buildings. The water temperature is 88 °C and a tita-

471 nium heat exchanger is employed to isolate the

472 recirculation water due to its high salinity.

473 The use of GSHP systems in Greece is not as widespread

474 as in some other countries, especially in Central and

475 Northern Europe. The exact total number of such units

476 presently installed in the country is not known, but is esti-

477 mated to exceed 1000 with an installed capacity of over

478 1 30 MWth (Andritsos et al., 2015). This means that, with

479 a mean COP of 3.5 and for a heating equivalent load of

480 1800 h/yr, the thermal energy used for the estimated

481 installed capacity in the country is about 640 TJ/yr.

482 About 61% of the recorded installed capacity relates to

483 open-loop systems that use groundwater (Fig. 6), brackish

Fig. 6. Schematic diagram of an open-loop GSHP. Groundwater is abstracted from the ground, passed through a heat pump before being re-injected back into the ground or discharged at the surface.

water or sea water - approx. 30% represents closed vertical systems and the remaining 9% closed horizontal systems. The respective applications, with very few exceptions, cover the heating needs of buildings, particularly new ones. In recent years there has also been an increased interest in sea-water space cooling, especially for seaside hotels, operating only during the summer.

Despite the significant increase in the interest in, and the number of GSHP system installations during the past few years, the main obstacles to the dissemination of geother-mal systems in Greek buildings are the lack of information, the shortage of state support, and restrictions on free land, which applies to urban environments. Additional obstacles are the financial and economic crisis of the past five years and the stagnation of the construction sector, which have slowed down a greater market penetration of GSHPs. During the past few years GSHP systems have also faced competition from natural gas and air-to-water heat pumps, which are more economically attractive.

3.3. Biomass energy applications

Wood and wood waste are traditionally an important source of fuel for heating buildings in Greece. In the countryside and particularly in small communities that are located near sources of timber, a large percentage of households is heated with firewood. Moreover, in these places, firewood is used for other energy-consuming household chores, such as cooking and water heating (Michopoulos et al., 2014). The most common timber for firewood is oak, olive and beech, depending on the region and the availability. The burning of wood in fireplaces or stoves is also used as a means of heating in many residential buildings in urban areas. It is noteworthy that a fireplace is considered a luxurious accessory and is usually found in larger urban houses and apartments to "decorate" the living room. In apartments with a fireplace or wood stove, the latter supports the basic heating system, which is usually a two-way oil- or gas-fired central heating system, the most common means of heating buildings in Greece (Papamanolis, 2006). More rarely, more advanced biomass heating systems can be found in Greek buildings, in special boilers for heating water that is either used for heating the interior of the respective building through a central heating system or is used directly.

The tendency to use firewood for heating has been declining in Greece since the early 1990s primarily because of the change in the way buildings are heated in the countryside. This trend appears to have been checked in recent years when the economic crisis that has affected the country, combined with increased prices and taxes imposed on alternative fuels, particularly oil and natural gas, has caused citizens to turn to more economical solutions (Zafeiriou et al., 2011). In 2012, the year with the highest recorded level of biomass energy consumption, 41,116 TJ of energy from the burning of wood and wood waste was consumed by the building sector, mainly to serve heating

8 N. Papamanolis / International Journal of Sustainable Built Environment xxx (2015) xxx-xxx

539 needs. This amount is increased compared to the corre-

540 sponding consumption of the year 2008 (27,816 TJ) by

541 47.8% (Eurostat, 2015b). An important reason for this

542 increase was the decision by the government to bring the

543 excise duty on heating fuel into line with that of fuel oil.

544 This meant that the cost of one ton of heating fuel shot

545 up from 800-900 € in the winter of 2011-2012 to 1500546 1 600 € in the winter of 2012-2013. This led to a very signif-

547 icant increase in heating costs (it should be noted that a

548 house of 120 m2 needs an average of two tons of heating

549 oil in the winter in Greece). Suddenly, at the beginning of

550 the winter of 2012-2013, consumers began to display a

551 marked preference for firewood as a heating fuel. Many cit-

552 izens bought wood-burning stoves and numerous fireplaces

553 were constructed in existing buildings. At the same time

554 there was a dramatic increase in the demand for and con-

555 sumption of firewood, which had the following negative

556 consequences

557 - Firewood prices increased by approx. 50% (from 100 €

558 to 150 € a ton).

559 - Firewood imports multiplied. According to press

560 reports, imports of firewood from Bulgaria reached the

561 point where they covered over 50% of domestic needs

562 (gR Reporter, 2012).

563 - There was an increase in the number of cases of illegal

564 cutting and trade of firewood (ILP, 2014).

565 - Serious atmospheric pollution problems were caused in

566 large urban centres, as well as pollution problems in

567 the interiors of buildings burning firewood for heating.

568 In Athens and other cities (Thessaloniki, Patras,

569 Herakleion and Yannina) the readings for the atmo-

570 spheric concentrations of suspended PM-10 and

571 PM-2.5 particles were as much as three times the

572 accepted limit, while there were also high concentrations

573 of particles and other pollutants in enclosed spaces

574 (NOA (National Observatory of Athens), 2013; Florou

575 et al., 2013; Saffari et al., 2013).

577 This tendency continued in the winter of 2013-2014,

578 with successive air pollution episodes mainly in the large

579 urban centres and, in response, recommendations by the

580 competent authorities to reduce the number of fires lit in

581 domestic fireplaces. In order to deal with this problem, in

582 January 2014 a Joint Ministerial Decision was issued stip-

583 ulating that in cases where the limits for concentrations of

584 suspended PM-10 particulates were exceeded, and for as

585 long as the limits continued to be exceeded, a discount of

586 70% would be granted on the cost of domestic electricity

587 as an incentive for people to use electricity in order to heat

588 buildings (Hellenic Gov., 2014). The effectiveness of this

589 measure has yet to be fully evaluated. However, it is likely

590 that, in conjunction with the relatively mild winter of 2013591 2014 in many parts of the country, the measure played a

592 part in the decline in the consumption of biomass that

593 occurred in 2013.

4. Conclusions 594

The implementation in Greece of the new framework of 595

interventions (legislative and other measures) concerning 596

the energy performance of buildings has unfortunately 597

coincided with a deep economic recession that has had, 598

and continues to have, a major impact on the building con- 599

struction sector. As a result, the support for renewable 600

energy applications and utilisation of climatic conditions 601

in buildings that this framework aims to provide has been 602

inhibited by the fact that the rate of construction of new 603

buildings and repair of existing ones has fallen drastically. 604

Nevertheless, the statistics show an upward trend in 605

renewable energy uses in buildings in the country during 606

the period of application of the measures. This trend, 607

which is mainly a result of the continuous increase that 608

occurred up until 2012, has been curtailed by the decline 609

that has taken place since 2013. A large part of this growth, 610

stemming from biomass and more particularly from the 611

burning of firewood to heat buildings during the cold sea- 612

son, is not very "healthy": it is linked to the phenomena of 613

illegal logging and rising pollution in urban centres. On the 614

other hand, indications of growth trends in solar energy 615

applications are welcome, although they have yet to sta- 616

bilise. Finally, geothermal applications remain at low 617

levels, regardless of their tendency. 618

The positive aspects of the picture presented by these 619

statistics, in accordance with which Greece has maintained 620

- and in some cases improved - its satisfactory ranking 621

among the EU countries with regard to the level of renew- 622

able energy applications in buildings, justify the measures 623

that have been taken by the State. It is very likely that with- 624

out these measures, the respective applications would have 625

failed to make any progress at all. Even the factors that 626

may be responsible for the decline that has occurred since 627

2013 in the consumption of energy from certain forms of 628

RES (market saturation of rooftop pv and measures 629

restricting the burning of biomass) do not conflict with this 630

finding. At the same time - and this is also very important - 631

it seems that the positive image is partly due to the fact that 632

the Greeks, under the pressure of the economic recession 633

and also of the constraints imposed by the new legislation, 634

understand and are more sensitive to the issues of energy 635

efficiency in their buildings and the value of renewable 636

energy applications as a means of improving that efficiency. 637

References 638

Andritsos, N., Dalambakis, P., Arvanitis, A., Papachristou, M., Fytikas, 639

M., 2015. Geothermal Developments in Greece - Country update 640

2010-2014, World Geothermal Congress 2015, Melbourne, Australia. 641

Balaras, C.A., Dascalaki, E.G., Droutsa, P., Kontoyiannidis, S., 2013. 642

Hellenic renewable energy policies and energy performance of 643

residential buildings using solar collectors for domestic hot water 644

production in Greece. J. Renew. Sustain. Energy 5, 041813. 645

ELSTAT (Hellenic Statistical Authority), 2013. Survey on Energy 646

Consumption in Households, 2011-2012. <http://www.statistics. 647

IJSBE 82 ARTICLE IN PRESS No. of Pages 9

25 June 2015

N. Papamanolis / International Journal of Sustainable Built Environment xxx (2015) xxx-xxx 9

gr/portal/page/portal/ESYE/BUCKET/A0805/PressReleases/A0805_ SFA40_DT_5Y_00_2012_01_F_EN.pdf>.

ELSTAT (Hellenic Statistical Authority), 2015. Building Activity. <http:// www.statistics.gr/portal/page/portal/ESYE/PAGE-themes?p_param= A1302>.

EPIA (European Photovoltaic Industry Association), 2014. Global Market Outlook for Photovoltaics 2014-2018. <http://www.epia. org/fileadmin/user_upload/Publications/EPIA_Global_Market_ Outlook_for_Photovoltaics_2014-2018_-_Medium_Res.pdf>.

ESTIF (European Solar Thermal Industry Federation), 2014. Solar Thermal Markets in Europe, Trends and Market Statistics 2013. <http://www.estif.org/fileadmin/estif/content/market_data/down-loads/solar_thermal_markets2013_v01.pdf>.

European Parliament and Council, 2003. Directive 2002/91/EC of 16 December 2002 on the energy performance of buildings, Off. J. Eur. Union L 001, 04/01/2003, 65-71.

European Parliament and Council, 2009. Directive 2009/28/EC of 23 April 2009 on the promotion of the use of energy from renewable sources and amending and subsequently repealing Directives 2001/77/ EC and 2003/30/EC, Off. J. Eur. Union L 140, 5/6/2009, 16-62.

European Parliament and Council, 2010. Directive 2010/31/EU of 19 May 2010 on the energy performance of buildings (recast). Off. J. Eur. Union L 153, 18/06/2010, 13-35.

Eurostat, 2015a. Supply, transformation, consumption - all products -annual data [nrg_100a] Last update: 04-02-2015. <http://appsso. eurostat.ec.europa.eu/nui/show.do?dataset=nrg_100a&lang=en>.

Eurostat, 2015b. Supply, transformation, consumption - renewable energies - annual data [nrg_107a] Last update: 04-02-2015. <http:// appsso.eurostat.ec.europa.eu/nui/show.do?dataset=nrg_107a&lang= en>.

Florou-Kalli, K., Pikridas, M., Pandis, S.N., 2013. Wintertime Air Pollution and the Greek Financial Crisis, EGU General Assembly 2013. Austria, Vienna.

Giakoumi, A., 2009. Current State of Heating and Cooling Markets in Greece. CRES, Greece, p. 38.

GR Reporter, 2012. News from Greece, Over 50% of the firewood in Greece is imported from Bulgaria. <http://www.grreporter.info/en/ over_50_firewood_greece_imported_bulgaria/7846>.

HELAPCO (Hellenic Association of Photovoltaic Companies), 2014a. Greek PV Market Statistics 2013. <http://helapco.gr/wp-content/ uploads/pv-stats_greece_eng-2013.pdf>.

HELAPCO (Hellenic Association of Photovoltaic Companies), 2014b. A practical guide for investments in photovoltaics (in Greek). <http:// helapco.gr/pdf/PV_Investment_Guide_April2014.pdf>.

HELAPCO (Hellenic Association of Photovoltaic Companies), 2015. Greek PV Market Statistics 2014. <http://helapco.gr/pdf/pv-stats_-greece_2014_Feb2015.pdf>.

Hellenic Government, 1979. Decree Law 1/6/1979, Thermal Insulation Code for Buildings, The Hellenic Official Gazette, 362/D/1979.

Hellenic Government, 2008. Law 3661/2008 "Directions for reducing energy consumption in buildings and other regulations", The Hellenic Official Gazette, 89/B/2010.

Hellenic Government, 2010. Joint Ministerial Decision D6/B/5825/ 20.04.2010, "Endorsement of Energy Performance Buildings Regulation", The Hellenic Official Gazette, 407/B/2010.

Hellenic Government, 2013. Law 4203/2013 "Regulations on renewable energy issues and other provisions", The Hellenic Official Gazette, 235/ A/2013.

Hellenic Government, 2014. Joint Ministerial Decision D5/HL/B/F29/ 238, "Special subsidy for household electricity consumption for dealing with air pollution by suspended particles", The Hellenic Official Gazette, 5/B/2014.

HMCS (Hellenic Ministry of Culture and Sports), 2010. The "Green Tourism: programme. <http://www.yppo.gr/2/g22.jsp?obj_id= 42433>.

HME (Hellenic Ministry of Environment), 2010. The "Energy Efficiency of Household Buildings" programme. <http://exoikonomisi.ypeka.gr/ Default.aspx?tabid=652&language=en-US>.

HME (Hellenic Ministry of Environment), 2012. The "Building the Future" programme. <http://www.ktizontastomellon.gr/>.

HME (Hellenic Ministry of Environment), 2013. New beneficiaries in the programme "Energy Efficiency of Household Buildings". <http:// www.ypeka.gr/Default.aspx?tabid=389&sni[524]=2667&locale=el-GR&language=en-US>.

HME (Hellenic Ministry of Environment), 2014. Statistical data for issued energy performance of buildings certificates (in Greek). <http://www. ypeka.gr/LinkClick.aspx?fileticket=SGqqw0loPN8%3d&tabid=367& language=el-GR>.

HOEM (Hellenic Operator of Electricity Market), 2014. RES & CHP Monthly Statistics, December 2013. <http://www.lagie.gr/filead-min/groups/EDRETH/RES/2013_12_GR_MONTHLY_RES.pdf>.

ILP (Illegal Logging Portal), 2014. Countries & Regions, Europe, Greece. <http://www.illegal-logging.info/regions/greece>.

Karteris, M., Papadopoulos, A.M., 2012. Residential photovoltaics systems in Greece and in other European countries: a comparison and an overview. Adv. Build. Energy Res. 6 (1), 141-158.

Lambrakis, N., Katsanou, K., Siavalas, G., 2014. Geothermal fields and thermal waters in Greece: an overview. In: Baba, A., Bundschuh, J., Chandarasekharam, D. (Eds.), Geothermal Systems and Energy Resources: Turkey and Greece. CRC Press, Taylor and Francis, London, pp. 25-45.

Loulas, N.M., Karteris, M.K., Pilavachi, P.A., Papadopoulos, A.M., 2012. Photovoltaics in urban environment: a case study for typical apartment buildings in Greece. Renewable Energy 48, 453-463.

Mendrinos, D., Choropanitis, I., Polyzou, O., Karytsas, C., 2010. Exploring for geothermal resources in Greece. Geothermics 39 (1), 124-137.

Michopoulos, A., Skoulou, V., Voulgari, V., Tsikaloudaki, A., Kyriakis, N.A., 2014. The exploitation of biomass for building space heating in Greece: energy, environmental and economic considerations. Energy Convers. Manage. 78, 276-285.

NOA (National Observatory of Athens), 2013. Preliminary results on the winter atmospheric pollution in five large Greek cities (in Greek). <http://www.noa.gr/images/news/press_release_pm_experiment_re-sults.pdf>.

Papamanolis, N., 2006. Characteristics of the environmental and energy behaviour of contemporary urban buildings in Greece. Arch. Sci. Rev. 49 (2), 120-126.

Papamanolis, N., 2015. An overview of solar energy applications in buildings in Greece. Int. J. Sustain. Energy (in press).

Papamanolis, N., Mandalaki, M., 2011. Technologies and Sustainable Policies for Decreasing Energy Consumption in Buildings in Greece, PLEA 2011, vol. 1. Louvain-la-Neuve, Belgium, 627-630.

Papamanolis, N., Tsitoura, M., 2013. The use of renewable energies in the new legislative framework for decreasing energy consumption in buildings in Greece. 4th Int. Conf. on RES, Nicosia, Cyprus.

Saffari, A., Daher, N., Samara, C., Voutsa, D., Kouras, A., Manoli, E., Karagkiozidou, O., Vlachokostas, C., Moussiopoulos, N., Shafer, M.M., Sioutas, K., 2013. Increased biomass burning due to the economic crisis in Greece and its adverse impact on winter-time air quality in Thessaloniki. Environ. Sci. Technol. 47 (23), 13313-13320.

Zafeiriou, E., Arabatzis, G., Koutroumanidis, T., 2011. The fuelwood market in Greece: an empirical approach. Renew. Sustain. Energy Rev. 15 (6), 3008-3018.