Consideration of the User in the Estimation of Heat Demand in Buildings

Although Poland is one of the leading recipients of the waste stream in the European Union (EU), it is at the same time below the average in terms of efficiency of their use/utilization. The adopted technological solutions cause waste processing rates to be relatively low in Poland. As a result, the report of the Early Warning and Response System (EWRS) of the EU indicated Poland as one of the 14 countries of the EU which are at risk in terms of possibility of achieving 50% recycling of waste. This article discusses the implemented technological solutions, and shows the profitability of the investment and the values of the process heat demand both for extractor and reactor. The experimental part analyzed the composition of the input and output of the process and compared it to the required fuel specifications. Attention was drawn to the need to improve the recycling process in order to increase the quality of manufactured fuel components. As potential ways of solving the problem of low fuel quality, cleaning the sorted reaction mass from solid particles and extending the technological line with a distillation column have been proposed. The recommended direction of improvement of the technology is also the optimization of the process of the reactor’s purification and removal of contaminants.

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Mitigating heat demand peaks in buildings in a highly renewable European energy system

Energy ◽

10.1016/j.energy.2021.120784 ◽

2021 ◽

pp. 120784

Author(s):

Elisabeth Zeyen ◽

Veit Hagenmeyer ◽

Tom Brown

Keyword(s):

Energy System ◽

Heat Demand

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Solar Field Output Temperature Optimization Using a MILP Algorithm and a 0D Model in the Case of a Hybrid Concentrated Solar Thermal Power Plant for SHIP Applications

Energies ◽

10.3390/en14133731 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3731

Author(s):

Simon Kamerling ◽

Valéry Vuillerme ◽

Sylvain Rodat

Keyword(s):

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Solar Thermal ◽

Outlet Temperature ◽

Field Mass ◽

Heat Demand ◽

Process Heat ◽

Solar Field ◽

Control Trajectory

Using solar power for industrial process heat is an increasing trend to fight against climate change thanks to renewable heat. Process heat demand and solar flux can both present intermittency issues in industrial systems, therefore solar systems with storage introduce a degree of freedom on which optimization, on a mathematical basis, can be performed. As the efficiency of solar thermal receivers varies as a function of temperature and solar flux, it seems natural to consider an optimization on the operating temperature of the solar field. In this paper, a Mixed Integer Linear Programming (MILP) algorithm is developed to optimize the operating temperature in a system consisting of a concentrated solar thermal field with storage, hybridized with a boiler. The MILP algorithm optimizes the control trajectory on a time horizon of 48 h in order to minimize boiler use. Objective function corresponds to the boiler use, for completion of the heat from the solar field, whereas the linear constraints are a simplified representation of the system. The solar field mass flow rate is the optimization variable which is directly linked to the outlet temperature of the solar field. The control trajectory consists of the solar field mass flow rate and outlet temperature, along with the auxiliary mass flow rate going directly to the boiler. The control trajectory is then injected in a 0D model of the plant which performs more detailed calculations. For the purpose of the study, a Linear Fresnel system is investigated, with generic heat demand curves and constant temperature demand. The value of the developed algorithm is compared with two other control approaches: one operating at the nominal solar field output temperature, and the other one operating at the actual demand mass flow rate. Finally, a case study and a sensitivity analysis are presented. The MILP’s control shows to be more performant, up to a relative increase of the annual solar fraction of 4% at 350 °C process temperature. Novelty of this work resides in the MILP optimization of temperature levels presenting high non-linearities, applied to a solar thermal system with storage for process heat applications.

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Geospatial Analysis of the Building Heat Demand and Distribution Losses in a District Heating Network

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi5120219 ◽

2016 ◽

Vol 5 (12) ◽

pp. 219 ◽

Cited By ~ 5

Author(s):

Tobias Törnros ◽

Bernd Resch ◽

Matthias Rupp ◽

Hartmut Gündra

Keyword(s):

District Heating ◽

Geospatial Analysis ◽

Heat Demand ◽

Building Heat

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Analysis of Heat Demand and Supply in Multicomponent Distillation Systems.

JOURNAL OF CHEMICAL ENGINEERING OF JAPAN ◽

10.1252/jcej.27.188 ◽

1994 ◽

Vol 27 (2) ◽

pp. 188-193 ◽

Cited By ~ 1

Author(s):

Damrong Pradubsripetch ◽

Yuji Naka ◽

Zhang Fan

Keyword(s):

Demand And Supply ◽

Multicomponent Distillation ◽

Heat Demand

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On the correlation between building heat demand and wind energy supply and how it helps to avoid blackouts

Smart Energy ◽

10.1016/j.segy.2021.100009 ◽

2021 ◽

Vol 1 ◽

pp. 100009

Author(s):

Mark Z. Jacobson

Keyword(s):

Wind Energy ◽

Energy Supply ◽

Heat Demand ◽

Building Heat

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Reduction of Oxygen Consumption, Insensible Water Loss, and Radiant Heat Demand with Use of a Plastic Blanket for Low-Birth-Weight Infants Under Radiant Warmers

PEDIATRICS ◽

10.1542/peds.74.6.1022 ◽

1984 ◽

Vol 74 (6) ◽

pp. 1022-1028

Author(s):

Stephen Baumgart

Keyword(s):

Oxygen Consumption ◽

Birth Weight ◽

Low Birth Weight ◽

Water Loss ◽

Very Low Birth Weight ◽

Radiant Heat ◽

Low Birth Weight Infants ◽

Heat Demand ◽

Radiant Heater ◽

Radiant Warmer

Eight very low-birth-weight premature infants (mean birth weight 1.11 ± 0.05 [SEM] kg, mean gestation 30 ± 1 weeks, and mean age 9 ± 2 days) were studied under servocontrolled radiant warmers with and without a loosely fitted, transparent, and flexible Saran plastic blanket. Metabolic rate was significantly less in all infants when covered by the blanket (oxygen consumption was 7.99 ± 1.13 mL/kg/min v 9.00 ± 1.10 mL/kg/min uncovered, P < .001). There were also significant reductions in insensible water loss (1.86 ± 0.18 v 1.25 ± 0.20 mL/kg/h, P < .01) and in heat demand from the radiant warmer (14.3 ± 1.3 v 9.9 ± 1.4 mW/cm2, P < .001) when infants were nursed under the blanket compared with the control condition, respectively. Covering the critically ill, very low-birth-weight infant nursed under a radiant heater with a thin, transparent layer of Saran is beneficial in reducing oxygen consumption, insensible water loss, and the need for exposure to high levels of radiant heat. Further investigation to confirm the benefits and possible complications of plastic blankets should be conducted before routine use can be recommended.

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Investigation of Subsystems for Combination into a SOFC-Based CCHP System

Journal of Electrochemical Energy Conversion and Storage ◽

10.1115/1.4041727 ◽

2018 ◽

Vol 16 (2) ◽

Cited By ~ 1

Author(s):

Christof Weinlaender ◽

Johannes Albert ◽

Christian Gaber ◽

Martin Hauth ◽

René Rieberer ◽

...

Keyword(s):

Operation Mode ◽

Combined Heat And Power ◽

Summer Season ◽

Solid Oxide ◽

Engineering Process ◽

Steam Reformer ◽

Start Up ◽

Heat Demand ◽

Negative Effect ◽

Combined Cooling

This paper presents the development of the subsystems for stationary biogas powered solid oxide fuel cell (SOFC)-based combined cooling, heat and power (CCHP). For certain applications, such as buildings, a heat-driven operation mode leads to low operating hours per year for conventional combined heat and power (CHP) systems due to the low heat demand during the summer season. The objectives of this study are the evaluation of an adsorber, a steam reformer, a SOFC, and an absorption chiller (AC). Biogas, however, contains impurities in the form of hydrogen sulfide (H2S), hydrogen chloride (HCl), and siloxanes in different concentrations, which have a negative effect on the performance and durability of the SOFC and, in the case of H2S, also on the catalyst of the steam reformer. This paper describes different experimental sections: (i) the biogas treatment with its main focus on H2S separation and steam reforming, (ii) the setup and start-up of a 10 cell SOFC stack, and (iii) test runs with an AC using a mixture of NH3 (ammonia)/H2O (water). The components required for the engineering process of the subsystem's structure are described in detail and possible options for system design are explained. The evaluation is the basis to reveal the improvement potentials, which have to be considered in future product developments. This paper aims at comparing experimental data of the test rigs to develop an understanding of the requirements for a stable and continuous operation of a SOFC-based CCHP operated by biogas.

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Experience With a Solar Heating ATES System for a University Building

Journal of Solar Energy Engineering ◽

10.1115/1.2930503 ◽

1994 ◽

Vol 116 (2) ◽

pp. 88-93 ◽

Cited By ~ 5

Author(s):

E. Hahne ◽

M. Hornberger

Keyword(s):

Solar Energy ◽

Heat Pump ◽

Waste Heat ◽

Heating System ◽

Solar Heating ◽

Coefficient Of Performance ◽

Solar Collectors ◽

Power Station ◽

Heat Demand ◽

Heat Store

At Stuttgart University, a solar heating system for an office building with laboratories and lecture rooms was installed in 1985. It consists of 211 m2 of unglazed solar collectors, a 1050 m3 water-flooded pebble bed heat store, and a heat pump. Heat can be supplied to the store from the solar collectors or from a power station (as waste heat). The whole system has worked successfully for five years under varied strategies. In the first two heating periods, the heating strategy was aimed to collect as much solar energy as possible. Thus, about 60 percent of the heat demand could be covered by solar energy; but the yearly heat pump coefficient of performance (COP) was only around 2.76. With an improved heat pump, a monthly COP of 3.6 was obtained. Heat losses from the storage amounted to about 20 percent.

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