Renewables and district heating: Eastern Europe keeps it warm

MILAN -- Long after the Iron Curtain was lifted, Europe's ex-Soviet nations often remain reliant on combined heat and power (CHP) plants feeding district heating schemes for which renewables could make an attractive fuel source. 

 

A legacy of centralized economic planning guided by the objective of providing universal access to housing and utilities, district heating (DH) traditionally played the starring role in urban heating systems in the planned economies behind the Iron Curtain.
The first Soviet electrification plan of 1920 and successive five-year plans emphasized cogeneration and waste heat recycling from turbine steam for district heating of urban residential areas and industrial facilities. Fuel savings at electric power stations — the major producer of waste heat — were an important performance indicator for the Soviet Ministry of Power and Electrification.
With a domestic oil economy devastated by its civil conflict, many of Russia's first power plants used peat for lack of alternatives. But growing urbanization and the development of the oil and gas industry after World War II led to the dominance of fossil fuels for DH across the communist bloc.
With the transition to market economies after the collapse of the Soviet system, these same countries, some of which have since joined the E.U., must grapple with the task of modernizing these networks without neglecting ambitious environmental targets amid difficult economic times and rising energy prices.

Euroheat and Power — the European industry association for the CHP and district heating and cooling sectors — estimates in its 2011 survey that in 2009 the share of citizens served by DH totalled 64 per cent in Latvia, 60 percent in Lithuania, 53 per cent in Estonia, 50 percent in Poland, 41 percent in Slovakia, 38 per cent in the Czech Republic, 23 percent in Romania, 17 percent in Slovenia and 10 percent in Croatia.
The share of recycled heat in these systems ranges from a high of 92 percent for Romania to a low of 38 percent in Slovakia and Estonia. Recycled heat is defined as: CHP including from combustible renewables; waste-to-energy plants; industrial processes independent of the fuel used for the primary process; and two thirds of the energy delivered by heat pumps.
Cogeneration is less common in Estonia since most of its electricity came from oil shale plants concentrated in one region. Meanwhile Russia's DH system boasts a trench length for the pipeline system of some 173,000 km.

Direct use of renewables — in heat-only boilers and non CHP installations — ranges from a high of around 14 percent in Estonia, Latvia and Lithuania to 2 percent or less in the Czech Republic, Poland, Romania and Slovenia.

In the E.U. 27 the share of recycled heat in DH increased from 70 percent in 1990 to 80 percent in 2006, with most from the “others” category. The share derived directly from renewables increased negligibly. In Germany, which along with Poland is the biggest DH market within the E.U., the share of recycled heat is 89.5 percent (mainly from coal, oil and natural gas with 10 percent from combustible renewables and waste).
From Euroheat's perspective, a modern DH system should be based on capturing waste heat and phase out the direct use of fossil fuels for heating. Johannes Jungbauer, of the European Affairs Office for Euroheat, emphasises that fuel source is not an accurate indicator of energy efficiency. Cogeneration increases the efficiency of primary fuels substantially in comparison to condensing power production and heat-only boilers.
Europe pushes for energy efficiency
With the E.U. seen as trailing in its goal of reducing primary energy consumption by 20 per cent by 2020, and heat losses from the E.U.-wide energy system estimated as high as 50 percent, energy efficiency is now at the heart of E.U. policy. In July 2012, the E.U. Parliament's Energy Committee unanimously voted in a new Energy Efficiency Directive (EED), repealing Directives 2004/8/EC and 2006/32/EC and enshrining the 20 percent efficiency target in law by stipulating mandatory measures (e.g., renovating public buildings and energy-saving schemes for utilities).
Member States must complete a “comprehensive assessment” by December 2015 of the potential of high-efficiency cogeneration and efficient district heating/cooling, set their own targets and present national efficiency action plans in 2014, 2017 and 2020.

DH offers several benefits over decentralized heating in areas of high heat load density. But the exact efficiency and environmental benefits depend on the fuel source, technical characteristics of the heat distribution system and boiler plants in addition to the institutional market structure. Unlike building-level boilers, DH enables fuel switching and can run on a wider variety of fuels, such as coal, oil, natural gas, municipal or industrial waste, geothermal, peat and biomass.
Euroheat emphasizes heating's contribution, and particularly the recuperation of waste heat to achieving energy efficiency targets: 40 percent of the E.U.'s final energy demand is for heating (space, water and low temperature industrial processes) and largely met through imported fuels or low-efficiency electricity. If progress in achieving the 2020 targets is found insufficient in a 2014 review, national energy efficiency targets will be proposed. The plenary vote on the EED is scheduled for September.
“Of course we appreciate it,' says Jungbauer, of the EED, 'but we were hoping for more. Article 10, which includes an energy efficiency obligation scheme, has been watered down and could have been stronger.” As he describes it, results will depend on how Member States choose to implement the directive: “The EED raises awareness but there are a lot of ‘shalls’ and ‘shoulds’ in the text.”

Poland aims for cleaner power

For the E.U.'s largest coal producer — Poland — where domestic hard coal accounts for around 74 per cent of energy production, meeting the E.U.'s 2020 goal of reducing CO2 emissions by 20 percent will be particularly challenging and further complicated by the E.U.'s 2011 Industrial Emissions Directive which necessitates investment to reduce particulates and SOx/NOx emissions. In 2013 the “white certificates” scheme for emissions trading will be introduced to ensure that energy companies meet their energy efficiency obligations.
Allocations for CO2 emission are currently obtained free of charge but from 2013 the number of allowances will be gradually decreased to zero in 2027 and the shortfall will have to be purchased through the Polish Power Exchange.
Currently renewable energy sources (RES) account for less than 10 percent of national energy production, though Poland's share of the 2020 E.U. target is 15 percent energy from RES. Since 2005, Polish support for RES has consisted of a rainbow of tradable renewable energy certificates in shades of green, yellow, red, violet and brown which are issued to producers of renewable energy, providing them with a secondary revenue stream. Poland's use of renewables in DH (CHP or not) in 2009 was around 7 percent, most of which was derived from combustible renewables.
DH is an important industrial sector in Poland. The Chamber of Commerce Polish District Heating estimates that around 500 companies operated in this sector earning an income of about €4.1 billion in 2010. With an urban share of 60 per cent, national DH capacity is 59,260 MW served by a trench length of 19,400 km of pipeline systems.
The Chamber, spurred on by the “Polish Energy Policy to 2030”, has recognized the potential of cogeneration and along with the Polish CHP Association has presented a program for developing cogeneration from its current 63 percent level to the Ministry of Economy.
With the average profitability of heating companies being far lower than the industrial average, the sector also faces serious competitive challenges which have seen the sector contract: from 2005 to 2009 DH capacity fell from 65,189 MWth to 59,970 MWth while district heat sales fell from 295 PJ to 239 PJ.

Renewables projects get underway

The renewable energy sources (RES) considered most feasible for district heating are biomass, geothermal and solar with biomass seen as the most viable.
Fortum, a Finnish energy company, has CHP assets in operation in Russia, Poland, Estonia, Latvia and Lithuania with a total heat production capacity of 14,107 MW in Russia and a combined 2,432 MW in the latter four countries. In 2011 it announced the inauguration of a new biomass CHP plant in Pärnu, Estonia, with a multifuel Circulating Fluidized Bed (CFB) boiler offering 100 percent fuel flexibility for using peat, wood and industrial waste. It also invested in a new biofuel CHP plant in Jelgava, Latvia, the first of its scale in Latvia. Its Czestochowa CHP plant in Poland uses hard coal and co-fires up to 25 percent biomass in a 186 MWth CFB boiler.
Dalkia has announced two biomass cogeneration projects in Poland, its largest biomass project to date. Around 700,000 metric tons of biomass will replace coal, supplying electricity to the national grid and heating to the 700,000 inhabitants of Lødz and Poznan served by DH. The project will require a €70 million investment.
Solar and geothermal energy as fuel sources are naturally limited by their availability. Demonstration solar DH plants (large-scale solar thermal technology generating heat from large collector fields) operate at competitive costs in Sweden, Denmark, Germany and Austria but are new to Eastern Europe. A consortium of Slovenian and Austrian companies completed the first large-scale solar thermal plant in Slovenia in March 2012. Solar collectors with an area of 842.3 m² or 590 kW feed into a 93 m³ storage tank, which in turn feeds into the Vransko DH grid supplying heat to around 2500 inhabitants. Geothermal district heating dates back to Roman times. Iceland, where 99 per cent of the population is currently served by DH, is in the enviable position of using its geothermal resources to generate 77 per cent of its district heating. Geothermal energy has potential in Poland and Hungary, the latter being considered a 'hot' market by the European Geothermal Energy Council. Hungary currently has around 16 geothermal district heating projects in operation with over 500 MWth of installed capacity and this number will double by 2014. PannErgy, a Hungarian energy company, focuses on the use of geothermal resources for DH energy in the Carpathian basin. With technology and know-how supplied by Iceland's Mannvit and in partnership with municipalities, a 3.2 MWth plant (replacing a natural gas based boiler) is already in operation in Szentlorinc while another will soon come online near Miskolc.
The potential of municipal and industrial waste as a DH fuel is significant and under-used. Polish waste management legislation adopted in 2011 — whereby land filling must be significantly reduced from the current 90 percent level — opens an opportunity for investments in waste-to-energy plants. The E.U. has also announced its intention to “phase-out biodegradable waste going to landfill in 2020-2025”.
Currently the Czech Republic, Slovakia, Poland and Hungary only host a handful of installations for generating heat or power from municipal waste. Fortum has announced a new waste-to-energy CHP plant and distribution company in Klaipeda, Lithuania, in a joint venture with the City of Klaipeda. Commercial operation is planned for 2013, when 270,000 tons of municipal and industrial waste will be expected to produce around 150 GWh of electricity and 400 GWh of heat annually.

The outlook for renewables DH

While RES are associated with localized energy production, DH systems work on a centralizing economies-of-scale principle. The E.U. Energy Roadmap 2050 emphasizes that decentralized and centralized systems must increasingly interact: “In the new energy system, a new configuration of decentralized and centralized large-scale systems needs to emerge and will depend on each other, for example, if local resources are not sufficient or varying in time.”
And CHP DH systems can even be used to balance fluctuating electricity production from intermittent renewables, such as wind or solar. For example, on excessively windy days overcapacity can be shifted from feeding the grid to using heat pumps to heat water. Tørshavn in the Faroe Islands is setting up a 10 MW boiler to link its DH system to the grid. In Germany a research project co-ordinated by the Steinbeis Research Institute for Solar and Sustainable Thermal Energy Systems is also examining solutions for decentralized feed-in to solar district heating systems.
District heating's fuel flexibility, along with extensive inherited networks, offers great potential for Eastern Europe's energy future. But due to its synergy aspects, DH has never fitted neatly into energy statistics or policy. National energy policies must embrace DH more closely to achieve E.U. energy policy targets in energy efficiency or in the use of renewables and CHP.

http://www.renewableenergyworld.com/rea/news/article/2012/09/renewables-and-district-heating