Peak Load Boiler House Stage I
The Peak Load Boiler House is the first element of the entire investment – the Waste to Energy Plant (WTE Plant). Once the WTE Plant is started up, it will serve as a back-up heat source, which will primarily be used during peak heat demand (e.g. severe frost). It will also perform a safety function.
The Peak Load Boiler House which meets the highest emission standards is equipped with two water boilers that can generate heat from two types of environmentally friendly fuels – natural gas or light fuel oil. It is interesting to note that the fuel type is convenient to change because it does not require a lengthy boiler shutdown and modification of its operation, but only the appropriate selection in the instrumentation & control system. For residents, this action will be unnoticeable – it will not affect the continuity of heat supply.
The heart of the boiler house are two oil- and gas-fired boilers into which heating water is pumped. The water flowing through them is heated to the required temperature and then transferred back to the Municipal District Heating System. Water temperature does not have a fixed, single value. It is determined on an ongoing basis, as a result of the current demand of the
Municipal District Heating System and the ambient temperature. The boiler house is therefore a source of heat for the system, but it must fully cooperate with it and adapt to the needs of consumers in each case.
The Peak Load Boiler House features not only boilers, but also a lot of associated equipment, such as pumps responsible for the continuous flow of hot water to the consumers of heat from the Municipal District Heating System, fire protection system with the pumping station and water tank, liquid fuel tanks for the boilers (providing more than 4 days of operation of the boiler house at full power), diesel generator ensuring continuous operation of the boiler house in case of power failure and a modern control system for the entire plant. The boiler house will be able to fully cooperate with other heat sources and will be an integral part of the entire heating system of the city of Olsztyn.
WTE Plant Stage II
The Waste to Energy Plant is the second element of this investment of key importance for the residents of Olsztyn. It will be one of the most modern plants of this type in Europe. The eco-power plant is a high-tech plant for energy recovery, i.e. production of electricity and heat from treated and selected municipal waste.
The WTE Plant will treat previously recycled municipal waste. Household waste, which is thrown into black bins, is transferred as mixed waste to recycling centers where it is sorted into different fractions. The fine fraction (ash, stones) is rejected on special screens. The separation residues, the so-called oversize fraction, is treated and dried to produce the energy fraction of municipal waste. It is a fuel of full value that will be combusted and converted into electricity and heat in the Waste to Energy Plant.
The WTE Plant will be equipped with a grate steam boiler in which the waste incineration process takes place on a moving grate. The heat generated in the boiler’s heating surfaces during this process heats the water and causes it to evaporate. The resulting steam, after further heating, is directed to the steam turbine, and then to the condenser, where it dissipates heat and turns into water, which again goes to the boiler heating surfaces, closing the steam-water cycle of the plant. The steam turbine, driven by steam, causes the generator to turn, which produces electricity. When condensing in the condenser, the steam dissipates its heat to the heating water, which after being heated, is fed into the municipal district heating system. It should be emphasized that during its normal operation, the WTE Plant will cover approx 35% of the heat demand of the residents of Olsztyn.
The annual production of electricity transferred to the so- called grid (i.e. after deducting own consumption) is estimated at over 73,000 MWh which translates into, i.a.:
Glowing of more than 83,000 100-watt light bulbs 24 hours a day, year-round.
Full charging of 10 million 4,000 mAh cell phone batteries.
Powering more than 18,000 electric cars for a year at 20,000 miles per year.
The plant will operate entirely in accordance with the latest environmental requirements. Environmental parameters are viewed online by the Voivodship Inspectorate of Environmental Protection (WIOŚ), which ensures full transparency during the entire lifetime of the plant.
Investment contractors and subcontractors
The main contractor for the Plant chosen by the company Dobra Energia dla Olsztyna is a consortium of two companies: Doosan Enerbility (previously: Doosan Heavy Industries & Construction) and Doosan Lentjes. This consortium is responsible for the construction and provision of fully green solutions such as an innovative boiler or steam turbine. The ongoing construction works are performed by a subcontractor, the leading Austrian construction company Strabag.
The main subcontractor responsible for the operation of the constructed Plant will be Urbaser, which is a global leader in the field of municipal waste management and treatment. The responsibilities of Urbaser will include:
- employing complete staff necessary to operate the WTE Plant during the operation period;
- responsibility for maintaining the plant in continuous operation and supplying heat to the Municipal District Heating System and supplying electricity to the power system;
- conducting ongoing maintenance and overhauls of the plant during its operation;
- responsibility for operating the plant in accordance with all environmental and legal requirements.
The contract engineer is Sweco Polska sp. z o.o. (previously: Sweco Consulting), with over 12 years of consulting experience in the area of thermal waste treatment, an engineering and consulting company that aims to implement sustainable, innovative and effective technical, technological and organizational solutions. The responsibilities of Sweco Polska include, among others:
- reviewing technical and design documentation,
- participation in factory acceptance of manufactured machinery and equipment,
- ensuring constant presence of the investor’s representatives on the construction site,
- technical support for Dobra Energia dla Olsztyna in the supervision of works carried out by the EPC contractor.
In 2021, 100 subcontracting companies, including the contract engineer and the EPC contractor, were working on the construction site, 77% of which were Polish companies (in 2020 – 20 companies, 55% of which were Polish).