Lahti population grew by 11.5% from 1990 to 2015 and energy consumption per capita by 4.4%. In the Lahti area, primary energy sums, equivalent to consumption, have increased from 3 663 GWh in 1990 to 4 268 GWh in 2015. This is mainly due to population growth, growing building stock and an increasing share of 1-2 person households. Our specific future challenge is traffic; its output increased by 59.5% from 1990-2015 (Fig. A1).
Our actions to change to renewable energies and increasing energy efficiency have dropped Lahti’s CO2 emissions per capita from 10.99 tons in 1990 to 6.9 tons of CO2e in 2015. Total emission have dropped from 1 023.9 kilotons of CO2e in 1990 to 717.1 kilotons of CO2e in 2015.
Over 40 energy efficiency measures have been taken and reported via SEAP. The total energy savings of SEAP actions between 2010-2020 are estimated to be 177 736 MWh, while increase in renewable energy production is 360 871 MWh. The most important measures have been the investments on low-energy premises by Lahti consortium and installation of landfill gas collection system in Kujala waste management area.
Since 2011, the city has measured building energy use in real-time. Lahti Premises’ total energy consumption decreased over 4% in 2011-2017 (Fig. A2). Due to union of municipalities in 2016, Lahti Premises obtained buildings that haven’t been under energy efficiency actions before.
To futher enhance the energy effiency of premises, city of Lahti signed a new Energy Efficiency Agreement for 2017-2025, targeting 7% energy saving by 2025 (from the 2017 level). This implements the EED-EC. Lahti Housing Ltd. had managed to save 8 949 MWh of energy by the end of 2016.
Over 95% of district heating is produced energy efficiently in the combined heat and power plant of Kymijärvi I-II. The Kymijärvi II power plant (2012) is a unique gasification power plant that uses SRF. A complete change to renewables in centralized energy production will be performed by 2020 (Fig. A3). In 2017, 40.5% of district heating was generated with renewables.
The share of renewables in Finland’s transport sector is currently 8.4% of the gross final energy traffic consumption.
Lahti Energy Ltd.’s district heating network is extensive, with over 90% of the population and 99% of the municipal buildings using district heating (Fig. A1). District heating in the densely populated city will continue to be significant in near future. Therefore, the biggest shift on renewables will be performed through energy production changes (Fig. A3). However, solar power plants and heat pumps are also becoming more common. A 460 panel solar power plant (2017) in the Lahti Winter Sport Arena was part of the ESCO project.
The current code of conduct for public building projects in Lahti emphasises the role of energy efficiency innovations in all building projects. These include, e.g. use of LED lamps, heat pumps and passive energy efficiency solutions (building architecture). Smart lightning technologies are used in Lahti Harbour pedestrian area (Fig. A4).
• Municipal building energy saving potential between 2010-2020: 95 000 MWh. This is governed through 2008 and 2017 Energy Efficiency Agreement. Hour-based follow-up created immediate changes in 2012-2014 (Fig. A.2)
• New municipal building code of conduct (2018) requires all new buildings to be low energy. All schools and office buildings must use less than 90 kWh/m2/a, while Finnish legislation sets the limit at 100 kWh/m2/a for these types of buildings. It is a very efficient measure for long term energy efficiency.
• 2012: More efficient landfill gas collection system in Kujala waste management area, energy savings 33 000 MWh by 2020.
• Lahti Housing rental property action plan, 7000 MWh energy savings 2010-2020.
• 2010-2018 Päijät-Häme project consumers’ energy advisory: Energy counselling targeted residents in the Lahti region (Fig. B1), not possible to evaluate savings.
• 2015-2018 Street lighting towards LED use, 6000 MWh by 2020.
• Since almost all municipality-owned buildings use district heating, the strategy is to renew the centralised energy production with renewables (Fig. A3).
• 2013: Lahti Energy Ltd- invested in Swedish hydro power (11 M€).
• 2013: Biogas production at Lahti Aqua wastewater treatment plants.
• 2014: Renewable Energy Possibilities audit by an energy consult.
• 2014: LABIO biogas production plant started operating (17 M€). Biogas is produced from bio waste and sewage sludge from Lahti Aqua. After digestion, the mass goes for composting and turns into soil. Its capacity is 80 000 tons of bio waste per year and biogas production up to 50 GWh (9 million m3) per year.
• 2015: ESCO (Energy Services Company) project started: Lahti Premises in co-operation with Siemens. Investment 10 M€, aiming to save 6 GWh of energy.
• 2015-2016: Lahti City Group organizations install at least six new electric car charging points
• 2017-2020: Building of Kymijärvi 3 power plant.
• Lahti Energy involved in cooperations with companies, e.g. Fazer Mills, milling by-products (oats husks) are utilized as energy. Lahti Energy delivers hot water and steam to Polttimo, a malting company, from the steam plant, built in 2016 on the Polttimo premises, which mainly uses woodchips.
• Lahti Energy delivers small-scale solar power systems to households and housing cooperatives, in cooperation with local companies. Lahti Energy has solar power systems at two of their own plants.
• To enhance alternative fuels, Lahti Energy Ltd. has installed six electric car charging stations, delivers charging stations and owns six alternative fuel cars.
Kymijärvi II, an innovative combined heat and power (CHP) gasification plant, started full-scale operation in 2012 (investment 165 M€) (Fig. B2). The district heating network forms a core of the energy system in Lahti. The clients’ energy meters are read through a remote access. All users can view their real-time energy data via online strict identification system.
The aim of Lahti city is to give open and easily available information on different renewable energy options. Residents can calculate energy efficiency and renewable energy options on single-building scale through Energiavalinta.fi (Fig. B3). The service uses open data sources (e.g. age and energy efficiency of buildings) and maps (e.g. geothermal energy potential and solar radiation maps). The e-service assists in comparing sustainable energy solutions, suitable for each particular building, and acts as a contact channel to local businesses. Budget 190 000 €.
In 2012, Lahti Housing Ltd. constructed three low-energy houses (56 rental apartments). The houses use geothermal or solar energy, employ energy recovery ventilation and have an excellent energy class. Also, the electrical system is energy efficient. The buildings have 20 solar panels (area 43 m2).
In 2013, an almost zero-energy house was completed by a company providing housing for the elderly (part of the Lahti City Group). The building uses central heating and partially solar energy. The consumption of electricity and heating energy is 50% less, compared to similar traditional house. In 2016, low-energy house (energy class A) for elderly was completed, building uses district heating and solar energy (Fig. B4).
In 2015, Lahti was awarded in the WWF Earth Hour City Challenge. Lahti was the Finnish winner that year, and among the 16 best woldwide. The evaluators appreciated the energy investments and concrete solutions Lahti has made.
In 2016, Lahti joined the FISU Network . We will strive to be emission free and waste-free, and to curb overconsumption by 2050. The intermediate climate change mitigation goals are: CO2 emission –70 % by 2030 from 1990 level and carbon neutral by 2040. The roadmap for these city-wide targets are described and governed through Environmental Programme 2018-2030 and SECAP, which is under construction in Oct 2018.
• 2011-continues: Energy efficiency improvements of public buildings and street lightning. These actions form a majority of the energy saving potential of Lahti organisation. City of Lahti signed a new Energy Efficiency Agreement for 2017-2025, targeting 7 % energy saving by 2025 (from the 2017 level).
• 2015- continues: Climate Partnerships with companies and organizations (Fig. C1). We challenge companies to lower their CO2 emissions in cooperation with the Lahti University of Applied Sciences and Ladec, a development company. After surveying the company’s current emissions, the company makes a climate pledge and receives a diploma from the Mayor. Additionally, joining the Cleantech Finland network is encouraged.
• 2017: World Skiing games in Lahti and the walking passage had smart LED lighting and other environmentally friendly solutions (e.g. recycling) ware introduced. These are very visible measures for energy efficiency.
• Special focus is on reducing the energy consumption and CO2 emissions of traffic. Traffic will be the largest CO2 emission sector after 2020, when investments on centralised renewable energy production have been conducted. Innovative measures are needed: e.g. CitiCAP-project (UIA 2018-2020) aims to provide a personal carbon trading scheme for 1300 individuals of Lahti, which may cut 25 % of their mobility-related emissions.
• 2015-2018: The Lahti Energy company will invest 20 M€ in wind power.
• 2016 Lahti City Group target: Share of certified green electricity should be 10% by the end of 2020.
• 2017-2020: Lahti Energy Ltd. and the City Council have decided to build a new biofuel power plant, Kymijärvi III, in Lahti, which should be operational by 2020 (Fig. C2). With the new biofuel power plant, 80% of district heating will be generated from renewable sources. The investment will cost 150 M€. The old coal-operated power plant, Kymijärvi I, will then close. A large energy storage tank will be built to cope with energy consumption peaks. The new power plant will reduce our GHG-emissions considerably, as district heating will be more sustainable.
• Sustainability biomass criteria of Kymijärvi II-III: FSC or PEFC forestry certificates.
Lahti Energy Ltd. aims for development of local energy production to become coal-free and renewable (Fig. A3, C2). The biomass used in Kymijärvi III will largely come from nearby forests and create around 75 new jobs. Kymijärvi III’s energy efficiency is created through the use of the latest technology, heat recovery and condensing water from combustion gases. Efficient purification of condensation water enables it to be released into the river, as well as be used at the plant. Heat recovery will lower emissions (SO₂, NO/NOₓ, PM) significantly, which affects air quality. Resultant ash can be used as fertilizer in forests.
We have a strong focus on improving traffic system energy efficiency. Traffic GHG emissions, in Lahti, grew by 17% from 1990-2015. However, traffic output simultaneously grew by 59.5%. This is a national challenge; and although modern cars and buses have lower emissions, the total traffic increase has been so dramatic that it has overtaken the positive developments, in the traffic sector (Fig. C3). Lahti City has reached a preliminary long-term decision to have public transport buses change to electric buses. In other logistics, biogas car use will be enhanced.
Lahti has started an innovative project, CitiCAP (2018-2020), which aims to build a holistic data platform for mobility and build, pilot and implement a personal carbon trading scheme for mobility.
The industrial companies of Lahti area improve their energy efficiency through process development and local co-operation (Fig. C4).