Climate change, energy and emissions

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1. Climate change, energy and emissions


The year 2015 saw a continuation of measures aimed to curb climate change, such as improving energy efficiency. Measures related to the Municipalities’ Energy Efficiency Agreement, as well as measures related to the EU Sustainable Energy Action Plan (SEAP) continued and were also reported to the EU. The environmental and climatic impacts of the master plan were assessed, and the environmental and climatic goals were taken into consideration in the drafting of the new Lahti Strategy. Lahti Energia has an important role in reducing the greenhouse gas emissions in the area.

Lahti Energia’s key environmental goals are to reduce carbon dioxide emissions, minimize environmental impact, improve material and energy efficiency and increase environmental awareness. Lahti Energia reduces carbon dioxide emissions by increasing the use of renewable energy and reducing the use of coal. This is made possible by investments in new technology. Polttimo’s process heating plant, for instance, was granted an environmental permit in December 2015. The environmental permit for the Kymijärvi III power plant was delayed due to a change in plant design that called for updated noise modelling. Lahti Energia also invests in wind power by increasing the number of its wind power shares; the wind turbines are not located in Päijät-Häme but in windier areas. On the basis of the results of energy audits carried out at Lahti Energia in 2015, the Group’s energy efficiency plan has been updated and the implementation started. As in previous years, Lahti Energia sponsored Energy Awareness Week by paying for the materials for the second-graders and their teachers in the region’s schools. Lahti Energia organized a regional energy contest, which was won by Jalkaranta school class 2b with their poster. That same poster won Motiva’s national energy contest. This was the second year in a row that the winner came from Lahti. 

Safety and environmental observation rounds have continued in the company’s various locations. Observations made and measures taken are part of risk management and preventive action to minimize adverse environmental effects caused by the company’s activities. Also worthy of mention is the environmental permit granted to the Kymijärvi I power plant: the environmental permit process took more than 13 years—the application for the permit was originally submitted on 4 December 2002. On the last day of 2015, the permit was finally granted for the remaining operational years of the power plant.

In 2015, renewables made up 36.37% of the total power sales of Lahti Energia. In the Hollola-Lahti-Nastola area, 42.65% of the district heat was produced using renewable energy sources. Furthermore, municipality-owned buildings in Hollola, for instance, have switched to wood chips for heating, and Lahden Talot in Lahti uses geothermal hybrid systems. The improved energy efficiency can be seen in the following indicators.

Electricity consumption

Premises heat and electricity consumption

The relative change in vehicle traffic has been declining for two years; it may be partly due to the Matkakeskus building site, which has influenced traffic volumes on Highway 12, but it may also be that vehicle traffic has moved away from the city centre after Aleksanterinkatu was turned into a slow, one-way street. There is no evidence in the form of traffic counting data that cycling has increased. On the contrary, the traffic arrangements at the Matkakeskus building site have reduced the number of cyclists at the two counting points. Car dependency, that is, the number of registered passenger cars per thousand residents is constantly increasing.

Relative change in traffic

Carbon dioxide emissions from power plants and industries have continued to decline.

Carbon dioxide emissions

Almost all of the waste received by Päijät-Häme Waste Management Ltd. is utilized either as reusable material or for energy production. Separately collected burnable waste is utilized as fuel for Lahti Energia’s Kymijärvi II power plant and other power plants. Mixed waste is transported to Kotka for energy production. Biodegradable waste is treated in the digestion and composting plant of Labio Ltd. Separately collected glass, metal and cardboard was utilized to replace virgin raw materials. From the beginning of 2016, Finnish Packaging Recycling RINKI Ltd. handles the regional collection of packaging waste.

At Labio Ltd., the sludge from wastewater treatment plants of Lahti Aqua and six other municipalities is mixed with biodegradable waste collected. In the digestion plant, the resulting biogas, or methane, is collected. The plant is the first digestion plant in Finland to use dry digestion technology. Waste can be digested without added water so, unlike conventional digestion technology, the process will not produce concentrated wastewater, which would require a separate treatment process. The biogas reactors are heated by waste heat from composting plant exhaust air so that all the biogas can be utilized. The biogas plant produces up to 50 GWh (i.e., 9 million cubic metres) of raw biogas per year. The raw biogas is transmitted to Gasum’s biogas processing plant, where it is purified and fed into the natural gas network to be sold as transport fuel and recycled gas. After digestion, the material proceeds to compost. All in all, the process only takes about one-and-a-half months. All the composted material produced by Labio is re-used either in farming or to make growing media.

In 2015, 92 per cent of the municipal waste received by Päijät-Häme Waste Management Ltd. was reused. Of that amount, 33 per cent was reused as materials and 67 per cent was used for energy production. The amount of municipal waste dumped in landfills in 2015 was 35 kg per capita. The capacity of the incineration plants was less than expected, so the amount of waste that ended up in landfills was a little higher than planned.

Mixed waste amount

The wastewater produced by the 120,000 residents of the Lahti and Hollola region is treated at Lahti Aqua’s Kariniemi and Ali-Juhakkala sewage treatment plants. In 2015, a total of 11.6 million cubic metres of wastewater was treated. The plants are bio-chemical wastewater treatment plants where solid waste and sand are removed mechanically, organic matter and nitrogen are removed biologically and phosphorus is removed chemically. The phosphorus and organic matter load on water after the cleaning process showed a decrease of approximately 30% from the previous year. In the first quarter of 2015, the Ali-Juhakkala treatment plant did not meet the environmental permit conditions for the levels of ammoniacal nitrogen, but the other permit conditions were met. The levels were too high as a result of cold meltwaters.

The requirements of Lahti Aqua’s environmental permit were tightened in 2014. The largest hygienization plant in Finland for treated wastewater was opened in Lahti in May 2015. The hygienization plant processes treated wastewater from the Kariniemi and Ali-Juhakkala wastewater treatment plants before the water is released into the Porvoonjoki River. The hygienization is carried out with UV light. In the third and fourth quarters of the year, the faecal bacteria removal rate was almost 100%.

The biogas produced in the sludge process at Lahti Aqua’s wastewater treatment plants is utilized as heating energy. Of the total 12,468 MWh of energy produced, 59.3% was used for heating the wastewater treatment plants and the rest was sold to be used in Lahti Energia’s district heating network. The energy thus produced for the district heating network was equivalent to the annual heating energy consumption of 350 houses. All in all, the biogas reuse rate is 100%. After digestion and recovery of gas, the dry sludge is delivered to Labio, where the sludge is composted.

Lahti Aqua made major investments in 2015: the largest of these were the renovations of the Laune water abstraction site and Mustankallio water tower, as well as the wastewater hygienization plant. In a customer satisfaction survey, Lahti Aqua’s quality of services and operations were given the best possible rating from both Lahti and Hollola based customers.

Emissions to Porvoonjoki

Nastola waste waters

The Nastola wastewater treatment plant processed about 1 million cubic metres of wastewater. The new, more stringent environmental permit requirements for the Nastola wastewater treatment plant became effective in the fall of 2015, and the plant met the new permit conditions for the entire year. The new permit requires that the treated wastewater is hygienized. A new hygienization plant will be built for the Nastola wastewater treatment plant during 2016. Sludge from the Nastola wastewater treatment plant is delivered to Labio for composting. In the Smart Retro project during the spring of 2015, the City of Lahti and businesses operating in the city experimented with a variety of services that promote sustainable development. The experiment involved, among other things, the purchase of groceries online and a peer-to-peer delivery service of goods. In 2015, Lahti was among the 16 best cities in the international Earth Hour City Challenge. According to the jury, the energy and climate activities of Lahti are more extensive than those of most cities of comparable size, and the activities are varied and concrete.

Future challenges related to climate change, energy and emissions:
• More extreme weather phenomena related to climate change, and the risks associated with it.
• Hollola prepares for power failures and serious disruptions in the energy supply by providing backup systems for electricity, heating and water in new and recently built schools.
• Stopping the increase in electricity consumption.
• Increased use of renewable energy: if successful, the Kymijärvi III bioenergy plant will significantly improve the renewable energy rate of district heating.
• Increasing the utilization of waste as material.
• Sewage network repair backlog.
• Cutting dependency on cars.




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