[1] Announcement of the Sejm Speaker of the Republic of Poland on the promulgation of a consolidated text of the Act on renewable energy sources. Journal of Laws – Republic of Poland (Dziennik Ustaw Rzeczypospolitej Polskiej) 2021, Item 610 (in Polish).
[2] Regulation of the Minister of Development and Finance on the requirements for solid-fuel boilers. Journal of Laws – Republic of Poland (Dziennik Ustaw Rzeczypospolitej Polskiej) 2017, Item 1690 (in Polish).
[3] EN 303-5:2021: Heating boilers – Part 5: Heating boilers for solid fuels, manually and automatically stoked, nominal heat output of up to 500 kW – Terminology, requirements, testing and marking.
[4] Poland’s Energy Policy until 2040. Ministry of Climate and the Environment, Appendix to Resolution 22/2021 of the Council of Ministers, 2021 (in Polish).
[5] Commission Regulation (EU) 2019/2146 amending Regulation (EC) 1099/2008 of the European Parliament and of the Council on energy statistics, as regards the implementation of updates for the annual, monthly and short-term monthly energy statistics. OJ L 325, 16.12.2019.
[6] Directive (EU) 2018/2001 of the European Parliament and of the Council on the promotion of the use of energy from renewable sources. OJ L 328, 21.12.2018.
[7] Zima W., Ojczyk G.: Current status and prospects for solid multi-fuel boilers of low power. Rynek Energii 5(2013), 108, 50–56 (in Polish).
[8] Juszczak M., Pałaszynska K., Rolirad K., Janicki M., Szczechowiak E.: Attempt to use additives increasing ash melting point while firing agricultural biomass pellets in order to avoid slag production in the furnace. Ciepłownictwo, Ogrzewnictwo, Wentylacja 48(2017), 8, 320–326 (in Polish).
[9] Ciupek B., Urbaniak R., Judt W.: Experimental research of changes in co, nox and pm concentrations in flue gases during combustion of wood pellets with wheat seeds. Ciepłownictwo, Ogrzewnictwo, Wentylacja 50(2019), 2, 56–61.
[10] Orłowska A., Sroka K.: Changes in legal regulations concerning supplying households with heat. Rynek Energii 140(2019), 1, 38–47.
[11] Zima W., Ojczyk G.: Analysis of combustion of wood pellets as a substitute fuel in a low-power boiler. Arch. Combust. 35(2015), 2, 117–130.
[12] Ziebik A., Stanek W.: Energy effciency – selected thermo-ecological problems. Arch. Thermodyn. 41(2020), 2, 277–299.
[13]
https://www.herz-energie.at/pl/ (accessed 6 Sept. 2021).
[14]
http://www.ogniwobiecz.com.pl/ (accessed 12 Sept. 2021).
[15] Ecological Safety Mark: Certificate 1035. Inst. Chem. Process. Coal, Zabrze 2009 (in Polish).
[16]
https://www.keison.co.uk/ (accessed 17 Aug. 2021).
[17] Kuznetsov N.V., Mitor V.V., Dubovsky I.E., Karasina E.S. (Eds.): Thermal Calculation of Steam Boilers. Normative Method (2nd Edn.). Energia, Moscow 1973 (in Russian).
[18] Rutkowski Ł., Szczygieł I.: Calculation of the furnace exit gas temperature of stoker fired boilers. Arch. Thermodyn. 42(2021), 3, 3–24.