Cost-Optimal Plus Energy Building in a Cold Climate

Abstract

The main objective of this article is to propose possible requirements for cost-optimal plus energy building in a cold, heating dominated climate. The open question is what is more cost-effective: reduction of energy demand or increase of production from renewable energy sources. The target of the research was to check which solution has the lowest investment and maintenance costs. The analysis was made for a single-family house located in central Poland, including three different energy standards: WT2021 with energy need for heating ≤100 kWh/(m² year), NF40 with energy need for heating ≤40 kWh/(m² year) and NF15 with energy need for heating ≤15 kWh/(m² year)). Air and ground source heat pumps were used as a heat source and a photovoltaic system for the production of the electrical energy. For each case the investment and running costs were calculated very precisely, taking into account heating, ventilation, domestic hot water and auxiliary systems. Global cost for a 30-year period showed that house variants with air source heat pumps are more cost effective. The investment, replacement and maintenance cost related with energy systems have the biggest share in the global cost. Reaching the plus energy standard was possible only in the case of low-energy standard NF40 and NF15. Based on this research the proposed requirements for plus energy single-family residential buildings in central Poland are the following: the final (delivered) electrical energy demand (including heating, ventilation, domestic hot water and auxiliary systems) <45 kWh/(m² year) and the on-site electrical energy production >45 kWh/(m² year).

Annual Energy Performance of an Air Handling Unit with a Cross-Flow Heat Exchanger

“…The air handling unit with the cross-flow heat exchanger is schematically presented in Figure 1. It consists of air filters (1), exhaust fan (2), cross-flow heat exchanger (3), supply fan (4), heating coil (5), and cooling coil (6). In [44] an extensive analysis of a hybrid ventilation system consisting of earth to air heat exchangers, free cooling, and evaporative cooling air handling unit heat exchanger in a Near Zero Energy Building (nZEB) was presented.…”

“…The air handling unit with the cross-flow heat exchanger is schematically presented in Figure 1. It consists of air filters (1), exhaust fan (2), cross-flow heat exchanger (3), supply fan (4), heating coil (5), and cooling coil (6). Temperatures in Figure 1 are assigned according to EN 308 [46,50], which specifies methods to be used for laboratory testing of air-to-air heat recovery devices in buildings to obtain rating data and verify performance data given by manufacturers.…”

“…This problem is also very important in Poland, where a number of efficiency-oriented initiatives in buildings have been taken recently [2][3][4]. Introduction of the Directive on the Energy performance of buildings (EPBD) has resulted in the development of the building energy certification system and new requirements for thermal protection of buildings [5]. The Regulation of the Minister of Infrastructure and Development on the methodology to determine the energy performance of a building and energy performance certificates [6] presents in detail the calculation procedure to obtain energy performance indicators: EP (nonrenewable primary energy), EK (final energy), and EU (usable energy).…”

“…Firląg [5] analyzed plus energy residential buildings' solutions in a Polish heatingdominated climate at different thermal requirements. Balanced ventilation with annual heat recovery efficiency above 85% and 90% was analyzed, resulting in annual savings of EUR 580 in relation to the base variant with natural ventilation.…”

Designing the Composition of Cement-Stabilized Rammed Earth with the Association Analysis Application

“…One way to reduce the ecological impact and costs of construction works is to increase resource efficiency by reducing the transport of materials to the construction site [ 1 ]. This helps to ensure that construction is completed efficiently and on schedule.…”