The regression model for the evaluation of the quality parameters for pellets.

Abstract. In Latvia no European legislation concerning the quality of the production of pellets is adopted. Since the market is not regulated by any governmental regulations, biofuel testing is not compulsory. This aspect leads to a situation where pellets of various qualities are available on the market. The main objective of this paper is to compare the characteristics of the pellets which are produced in various regions of Latvia. The second goal is to develop a regression model which describes the influence of the independent aspects (physical parameters, price, trading form, transportation distance etc.) on the pellet quality. The quality parameters for the solid biofuels were determined according to the methods described in the Technical Specifications of the European Commission for Standardization. The regression model for the pellet quality has been implemented using the software STATGRAPHICS Centurion 16.1.15. The results of the research emphasize that the physical parameters of the pellets vary widely. Three regression models were built in order to describe the influence of the various parameters on the indicator (price per net calorific value) and on the mechanical quality of the pellets. The fitted Models were described by the regression equation given in the paper

Solutions for Energy Efficient and Sustainable Heating of Ventilation Air: A Review

A high energy efficiency and sustainability standards defined by modern society and legislation requires solutions in the form of complex integrated systems. The scope of this work is to provide a review on technologies and methods for the heating of ventilation air as a key aspect for high energy and environmental performance of buildings located in a cold climate. The results of this work are more relevant in the buildings where space heating consumes a significant part of the energy balance of a building, and air exchange is arranged in an organized manner. A proper design and control strategy, heat recovery, the use of renewable energy sources, and waste heat are the main aspects which must be considered for efficient and sustainable ventilation. This work focuses on these aspects. Air conditioning is not in the scope of this study

Integrated approach for sustainable development of energy, water and environment systems

The Conferences on Sustainable Development of Energy, Water and Environment Systems (SDEWES) at the beginning of the 21st century have become a significant venue for researchers to meet, and initiate, discuss, share, and disseminate new ideas in various disciplines of sustainable development. In 2002, the first conference was organised in Dubrovnik, Croatia and since then, 10 more successful conferences were realised. Following the success of international conferences in Dubrovnik, the organizing committees decided to organize the main conference and regional conferences all over the world in even years. In 2016, the second regional SDEWES conference, namely the 2nd South East European Conference on Sustainable Development of Energy, Water and Environment Systems, was held June 15-18 in Piran/Portorose, Slovenia while the 11th SDEWES conference was organised in Lisbon, Portugal on September 4-8. There were 10 special sessions dedicated to various sustain ability topics organised in both conferences