Europe is the world's largest producer of pellets. In 2014 there were produced 13.5 million tons of pellets, which is roughly 50 % of total world production. This production shows steady growth over several years with an average growth of 35 % between 2010–2013 and 11 % from 2013 to 2014. Production in the EU market caters mainly to heat market.
The paper is targeting verification of the possibilities to utilize solar systems with long-term heat storage in residential buildings. Several ways are evaluated how to connect the long-term heat storage system with hot-water storage tank (system with and without use of heat pump, different ways of charging the storage tank, variants with stand-by storage tanks). Evaluation of the system is performed by TRNSYS simulation software.
The article deals with the development of wind energy installations at the turn of the millennium. At the beginning of the 21st century wind energy has become the most dynamically evolving energy industry in Europe. In the period 2000 - 2015 it recorded highest energy growth in installed capacity among all other sources.
The year 2015 brought another expansion step for international certification ENplus for wood pellets. Only ENplus certification covers over other certifications fuels the entire supply chain including production and distribution of pellets and certified ENplus pellets can be purchased only from ENplus certified producers and traders.
In 2015 was in the Czech Republic the impressive increase in production of wood pellets. This increase goes hand in hand with the currently running grant program for replacement of old boilers, where it is possible to get for an automatic pellet boiler 127.5 thousand CZK. The market and the public on the situation responded positively – in a segment of ecological boilers for biomass combustion occurs after years of rapid growth attenuation.
Calculation of electricity production by photovoltaic systems can be performed by more or less simplified approach. Monthly balance method allows to include the influence of the temperature and solar irradiance into the monthly production calculation with use of the PV module parameters available in the technical datasheet. Individual PV module technologies are compared by the balance method.
The article describes use of Miscanthus sinensis for a manufacturing of pulp. Miscanthus sinensis is a perennial plant, its cultivating is easy and it can be used for various purposes.
In the first phase of the pulp preparation from Miscanthus, a laboratory preparation of pulp was done at the University of Pardubice in total amount of 6 individual batches. In the second phase a selected laboratory batch was prepared in a pilot production process and ca. 2000 g of pulp in total was generated for further tests.
Mechanical properties and also other properties typical for pulp were determined on prepared samples. The produced pulp was used in the next step for a preparation of fibre-cement boards. Their basic physico-mechanical parameters were also determined.
After evaluation of all data that we have, production of 500 kg of pulp was done. Then the pulp was used to produce fibre-cement boards in a mass production.
Article is dealing with gasification principles and gasifiers. Gasification is process for gas producing from solid fuels (coal, wastes, biomass). Producer gas can be used in cogeneration unit (piston engine or combustion turbine) for generating of heat and electricity with higher efficiency in comparison with combustion in boiler. All processes in gasifier taking place with regulated supply of gasification media (air, oxygen or steam) and reaction heat.
The paper presents an analysis of main design parameters influence (width of the air gap between the absorber and the covering glazing, emissivity of the absorber and insulation thickness) on the thermal performance of solar collector. High-quality flat-plate solar collector was chosen as a reference variant. The aim of the analysis is to show, to what extent it is possible to modify these parameters towards cheaper collectors without significant reduction in energy quality of solar collector in operation.
Second part of wind power series describes the beginning of wind power in Denmark and in Germany. Both countries began world leaders in wind power development and installation at the turn of the century. In addition the article tells several parallel stories of wind turbines that were significant for the wind branch as development stages or as the dead ends.
Pellet heating systems are a fairly new technology. Consequently there may be problems caused by the lack of experience with this technology. This also applies to pellet storage installations. Pellet stores have to fulfil a number of requirements to make sure that the pellet quality is maintained and safe operation is guaranteed.
The ENplus storage guideline describes the requirements to preserve fuel quality and provide safe storage of pellets for both professionals (such as installers) and consumers. It covers the technical properties of pellet stores as well as information on safe and adequate operation of these stores. They do not replace installation guidelines and instructions from pellet boiler/storage manufacturers but do take precedence over advice from installers/distributors. Planning aids and filling regulations from manufacturers of pellet storage, extraction systems and pellet boilers must be followed.
Professional practices are the cornerstone of successful market development.
Solid biofuels emit gaseous products in the air during their storage. These gases can be dangerous for health and the environment. The composition and quantity of the gaseous products is dependent on many factors. Temperature belongs among the most important factors. This article deals with the qualitative and quantitative analysis of gaseous products released during heating of forest wood chips. It was assessed usage gaseous products for indication of state of stored materials. Samples of wood chips were heated in a furnace in the temperature range 50–150 °C in increments of 50 °C for one hour. Analysis of the gases was performed by using an infrared spectrometer with Fourier transformation.
These findings can be used for correct selection of safety precaution.
Usage of solid biofuels increases due to substitution of fossil fuels. This fact contributes to increasing of danger of fire due to spontaneous combustion. Spontaneous combustion of these materials occurs during their storage in large piles. This tendency to spontaneous combustion is not the same, but is influenced by various factors. This article deals with the determination of tend to spontaneous combustion and evaluation of effect of moisture on self – ignition temperature of four kinds of wood chips. Evaluation of tendency to spontaneous combustion was performed according to standard EN 15188, in an isothermal furnace. The results have implications for the specification of safe conditions of storage of coal and wood substances and the selection of safety measures.
The aim of electricity distributor is that customers may be sourced if a constant amount of energy. When properly appliances division into groups according to how they can be turned off, it is possible to reduce the agreed value of the load shedding and save on fixed fees. The regulator load shedding so in the short term applies.
