Dynamic Heating Control Measured and Simulated Effects on Power Reduction, Energy, and Thermal Comfort in an Old Apartment Building with District Heating

2021 ◽  
Author(s):  
Hatef Hajian ◽  
Kaiser Ahmed ◽  
Jarek Kurnitski
Keyword(s):  
Thermal Comfort ◽  
District Heating ◽  
Power Reduction ◽  
Apartment Building ◽  
Dynamic Heating

scholarly journals The influence of heat loss from pipes in an unheated basement on the heating energy consumption of an entire typical apartment building

2020 ◽  
Vol 172 ◽  
pp. 12005
Author(s):  
Anti Hamburg ◽  
Targo Kalamees
Keyword(s):  
Energy Balance ◽  
Heat Loss ◽  
District Heating ◽  
Building Energy ◽  
Energy Performance ◽  
Heat Losses ◽  
Hot Water ◽  
Limited Information ◽  
Apartment Building ◽  
Heating Energy Consumption

The majority of old apartment buildings were designed with an unheated basement. Building service systems such as district heating heat exchangers and pipes for domestic hot water and for space heating are usually located in this unheated basement. In addition, these locations are connected with shafts. All these pipe’s heat losses increase air temperature in the basement. If these losses are included into the building energy balance, then they decrease heat loss through the basement ceiling. The basement’s heat balance is also dependent on heat loss from the basement envelope and outdoor air exchange in the basement. In early stages of design, designers and energy auditors need rough models to make decisions in limited information conditions. Once the effects of heat losses from pipes become apparent, they need to be factored into the buildings energy balance, and their effects on heat loss through the basement ceiling needs to be calculated. In this paper we analyse the effect these heat losses have on the service system’s heat gains and heat loss through an uninsulated basement ceiling at different basement insulation levels and with different thicknesses of pipe insulation. From our study we found that pipe losses in the basement increase the building energy performance value by at least 4 kWh/(m²∙a) and their impact on a renovated apartment building is very important.

scholarly journals Dynamic Approach to Evaluate the Effect of Reducing District Heating Temperature on Indoor Thermal Comfort

Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 25
Author(s):  
Benedetta Grassi ◽  
Edoardo Alessio Piana ◽  
Gian Paolo Beretta ◽  
Mariagrazia Pilotelli
Keyword(s):  
Heat Exchanger ◽  
Thermal Comfort ◽  
Urban Areas ◽  
Heating Temperature ◽  
Renewable Energy Sources ◽  
District Heating ◽  
Energy Performance ◽  
Building Stock ◽  
The Individual ◽  
High Temperature Operation

To reduce energy consumption for space heating, a coordinated action on energy supply, building fabric and occupant behavior is required to realize sustainable improvements. A reduction in district heating supply temperature is an interesting option to allow the incorporation of renewable energy sources and reduce distribution losses, but its impact on the final users must be considered. This aspect is especially critical as most European countries feature an old building stock, with poor insulation and heating systems designed for high-temperature operation. In this study, a complete methodology is devised to evaluate the effect of district heating temperature reduction on the end users by modeling all the stages of the system, from the primary heat exchanger to the indoor environment. A dynamic energy performance engine, based on EN ISO 52016-1:2017 standard and completed with a heat exchanger model, is implemented, and its outputs are used to calculate thermal comfort indicators throughout the heating season. As a practical application, the method is used to evaluate different scenarios resulting from the reduction of primary supply temperature of a second-generation district heating network in Northern Italy. Several building typologies dating back to different periods are considered, in the conservative assumption of radiator heating. The results of the simulations show that the most severe discomfort situations are experienced in buildings built before 1990, but in recent buildings the amount of discomfort occurrences can be high because of the poor output of radiators when working at very low temperatures. Among the possible measures that could help the transition, actions on the primary side, on the installed power and on the building fabric are considered. The investigation method requires a limited amount of input data and is applicable to different scales, from the individual building to entire urban areas lined up for renovation.

A study on the heat dissipation and thermal environment of a novel heated bed

2018 ◽  
Vol 42 (5) ◽  
pp. 629-651 ◽  
Author(s):  
Dengjia Wang ◽  
Xiaowen Wang ◽  
Yanfeng Liu ◽  
Penghao Chen ◽  
Jiaping Liu
Keyword(s):  
Thermal Comfort ◽  
Heat Dissipation ◽  
Thermal Environment ◽  
Process Analysis ◽  
District Heating ◽  
Heat Transfer Process ◽  
Time Sharing ◽  
Indoor Thermal Environment ◽  
Human Thermal Comfort ◽  
Heating Energy Consumption

This study proposes a novel heated bed that can heat the whole room in the daytime and heat the surroundings of the bed at night. The conditions of conversion between the daytime and nighttime are achieved by the opening and closing of the fan and vents. The simplified calculation method of heat dissipation of the bed was obtained via the flow and heat transfer process analysis in two heating modes. Numerical simulations of heat dissipation and indoor thermal environment under different conditions in the daytime and nighttime were performed using computational fluid dynamics (CFD) to master the indoor temperature distribution characteristics. The simulation results were compared with the experimental results and show good agreement. The results show that the maximum of heat dissipation can reach 1300 W in the daytime and the indoor thermal environment can meet the human thermal comfort requirement. At night, the bed can create a high-temperature circle around it, which can ensure the sleep thermal comfort of the human body at a cooler indoor thermal environment, whose temperature can be 5°C lower than normal conditions. The heated bed can achieve the time-sharing district heating of room and reduce the heating energy consumption significantly. This study can provide the design and selection basis for the heated bed.

scholarly journals Influence of heating elements dynamics on energy savings

2018 ◽  
Vol 9 (2) ◽  
pp. 169-173
Author(s):  
O. Šikula ◽  
O. Ladjedel ◽  
P. Charvát ◽  
L. Adjlout ◽  
S. A. Reffas
Keyword(s):  
Numerical Model ◽  
Thermal Comfort ◽  
Computer Simulations ◽  
Room Temperature ◽  
Energy Savings ◽  
Thermal Inertia ◽  
Living Room ◽  
New Type ◽  
Dynamic Heating

Dynamic heating computer simulations of one model typical living room heated alternatively by two types of heating bodies are presented in this paper. This contribution describes a numerical model of two heating elements (plate radiator and a new type of convector) showing different thermal inertia by using the TRNSYS software. The results show energy savings approximately of 10% for the new tested convector, where the thermal comfort is better in terms of reaching the required room temperature.

Co-optimization of multi-energy system operation, district heating/cooling network and thermal comfort management for buildings

2021 ◽  
Vol 302 ◽  
pp. 117480
Author(s):  
Lavinia Marina Paola Ghilardi ◽  
Alessandro Francesco Castelli ◽  
Luca Moretti ◽  
Mirko Morini ◽  
Emanuele Martelli
Keyword(s):  
Thermal Comfort ◽  
District Heating ◽  
Energy System ◽  
System Operation

scholarly journals Demand response of space heating using model predictive control in an educational office building

2019 ◽  
Vol 111 ◽  
pp. 03067
Author(s):  
Aleksi Mäki ◽  
Juha Jokisalo ◽  
Risto Kosonen
Keyword(s):  
Model Predictive Control ◽  
Thermal Comfort ◽  
Predictive Control ◽  
Demand Response ◽  
Energy Cost ◽  
Heating Temperature ◽  
District Heating ◽  
Cost Savings ◽  
Office Building ◽  
Space Heating

The building sector plays a remarkable role in decreasing of the overall global CO2 emissions since as much as 30% from the total global CO2 emission are generated in buildings. Demand response provides one possibility to tackle the problem. It can be used to decrease CO2 emissions in entire energy system in addition to providing energy cost savings for building owners and energy companies. In this study, the demand response potential was estimated in an educational office building that was heated by district heating. The potential was defined in respect of energy cost savings, energy flexibility and thermal comfort. Model predictive control was developed, which utilized the dynamic hourly district heating prices. The MPC algorithm written in the Matlab software, predicted the future heating demand while the optimization algorithm NSGA-II minimized the heating energy cost, maximized the energy flexibility and maintained acceptable thermal comfort by changing the space heating temperature setpoints. The operation of the MPC algorithm was tested in the IDA ICE 4.8 simulation software. As a result, the annual district heating energy costs could be reduced by 4.2% compared to the reference case with constant space heating temperature setpoint of 21 °C. The maximum flexibility factor attained was 14%. Acceptable level of thermal comfort was maintained throughout the simulation time.

scholarly journals The Effect Of Thermal Insulation Of An Apartment Building On The Thermo-Hydraulic Stability Of Its Heating System

2015 ◽  
Vol 23 (4) ◽  
pp. 8-18
Author(s):  
Mária Kurčová
Keyword(s):  
Thermal Comfort ◽  
Thermal Insulation ◽  
Thermal Characteristics ◽  
Heating System ◽  
Apartment Building ◽  
Hydraulic Stability

Abstract The contribution aims to investigate the effect of the decreased thermal losses of an apartment building due to the thermal insulation of opaque external building constructions and the replacement of transparent constructions. It emphasizes the effect of the thermal characteristics of external constructions on the functionality of the existing heating system in the building and the related requirements for the renovation of the heating system in order to ensure the hydraulic stability of the system and the thermal comfort of the inhabitants.

Sign in / Sign up

Export Citation Format

Share Document