An Investigation of Energy Consumption, Solar Fraction and Hybrid Photovoltaic–Thermal Solar Dryer Parameters in Drying of Chamomile Flower

2014 ◽  
Vol 10 (4) ◽  
pp. 697-711 ◽  
Author(s):  
Saeid Minaei ◽  
Ali Motevali ◽  
Barat Ghobadian ◽  
Ahmad Banakar ◽  
Seyed Hashem Samadi
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Air Temperature ◽  
Coefficient Of Performance ◽  
Pump Mode ◽  
Energy Fraction ◽  
Drying Time ◽  
Solar Dryer ◽  
Drying Behavior ◽  
Chamomile Flower

Abstract In this research, drying of a medicinal plant (chamomile) in a hybrid photovoltaic–thermal solar dryer with and without heat pump was investigated. The experiments were performed at three air speeds (0.5, 1, and 1.5 m/s), three levels of air temperature (40, 50, and 60°C), with and without using a heat pump. Results of analysis indicated that adding a heat pump to the photovoltaic solar dryer decreases drying time, energy consumption, and required specific energy. Solar energy fraction increased with decreasing air temperature and velocity. Analysis of the dryer-related parameters showed that the maximum and minimum thermal efficiencies were 33.8 and 16.4%, respectively, both in the no-heat-pump mode while with the heat pump, its maximum and minimum values were 38.4 and 19.7%, respectively. Moreover, the highest and lowest electrical efficiencies for the no-heat-pump mode were 13.4 and 9.1%, respectively; while using the heat pump, its maximum and minimum values were 14.1 and 10.4%, respectively. Results of analyzing the dryer’s coefficient of performance for drying chamomile showed that the highest and lowest coefficients of performance were 3.41 and 1.82, respectively. Eleven mathematical models were tested, and Page’s model was selected as the best for describing the drying behavior of chamomile flower.

Solar-Assisted Heat Pump Drying of Coriander: An Experimental Investigation

2018 ◽  
Vol 26 (04) ◽  
pp. 1850037 ◽  
Author(s):  
Abbas Alishah ◽  
Mohammad Valizadeh Kiamahalleh ◽  
Fereshteh Yousefi ◽  
Anita Emami ◽  
Meisam Valizadeh Kiamahalleh
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Solar Collector ◽  
Coefficient Of Performance ◽  
Air Flow Rate ◽  
Drying Time ◽  
Air Temperatures ◽  
Moisture Extraction ◽  
Heat Pump Drying ◽  
Time And Energy

In this study, the solar-assisted heat pump dryer was designed, manufactured, tested and optimized for drying operations of coriander for its preservation. The heat of drying was mainly provided by a solar collector and a heat pump with two experimental modes of turned on and off. The air temperatures and velocity were identified as the critical drying variables. The responses of the experiments were evaluated in terms of coefficient of performance (COP), energy consumption and the specific moisture extraction rate (SMER). Dehumidification of coriander from the moisture contents of 0.9 to 0.1 kg/kg was considerable. The results demonstrated that utilizing heat pump noticeably decreases the drying time (down to [Formula: see text]25%), energy consumption (down to [Formula: see text]12%) and increases SMER (up to [Formula: see text]20%). The increasing of air flow rate and air temperature significantly led to decreasing the drying time and energy consumption, however, increasing the COP and SMER.

scholarly journals Drying kinetics and quality aspects during heat pump drying of onion (Allium cepa L.)

2012 ◽  
Vol 1 (2) ◽  
Author(s):  
Nihar Ranjan Sahoo ◽  
Uma Sankar Pal ◽  
Sanjaya Kumar Dash ◽  
M.D. K. Khan
Keyword(s):  
Heat Pump ◽  
Air Temperature ◽  
Colour Change ◽  
Coefficient Of Determination ◽  
Drying Time ◽  
Hot Air ◽  
Thin Layer Drying ◽  
Quality Aspects ◽  
Heat Pump Drying ◽  
Air Dryer

A prototype heat pump dryer has been developed for drying of fruits and vegetables at low temperature and relative humidity to maintain the quality of dried product. Onions, of Nasik red variety were peeled, trimmed and sliced to 2 mm thickness. The onion slices were dried in the heat pump dryer at 35ºC (32 % R.H.), 40ºC (26 % R.H.), 45ºC (19 % R.H.) and 50ºC (15 % R.H.). Samples were also dried in a hot air dryer at 50ºC (52 % R.H.) for comparison. The drying rate increased with increase in drying air temperature, associated with reduced R.H., in the heat pump dryer. Drying took place mainly under the falling rate period. The Page equation, resulting in a higher coefficient of determination and lower root mean square error, better described the thin-layer drying of onion slices than the Henderson and Pabis equation. Heat pump drying took less drying time of 360 min and yielded better quality dried product, with higher retention of ascorbic acid and pyruvic acid and lower colour change, as compared to a hot air dryer at the same drying air temperature of 50ºC.

A numerical model for drying of spherical object in an indirect type solar dryer and estimating the drying time at different moisture level and air temperature

2018 ◽  
Vol 15 (3) ◽  
pp. 189-200 ◽  
Author(s):  
G. Arunsandeep ◽  
Abhay Lingayat ◽  
V.P. Chandramohan ◽  
V.R.K. Raju ◽  
K. Srinivas Reddy
Keyword(s):  
Numerical Model ◽  
Air Temperature ◽  
Moisture Level ◽  
Spherical Object ◽  
Drying Time ◽  
Solar Dryer

scholarly journals Modeling of heat pump tumble dryer energy consumption and drying time

2018 ◽  
Vol 37 (11) ◽  
pp. 1396-1404 ◽  
Author(s):  
Pero Gatarić ◽  
Brane Širok ◽  
Marko Hočevar ◽  
Lovrenc Novak
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Drying Time ◽  
Tumble Dryer

scholarly journals Performance Analysis of Air-to-Water Heat Pump in Latvian Climate Conditions

2014 ◽  
Vol 14 (1) ◽  
pp. 18-22 ◽  
Author(s):  
Janis Kazjonovs ◽  
Andrejs Sipkevics ◽  
Andris Jakovics ◽  
Andris Dancigs ◽  
Diana Bajare ◽  
...  
Keyword(s):  
Heat Pump ◽  
Air Temperature ◽  
Residential Buildings ◽  
Winter Season ◽  
Pump Energy ◽  
Energy Performance ◽  
Coefficient Of Performance ◽  
Heating Period ◽  
Climate Conditions ◽  
Eu Directive

Abstract Strategy of the European Union in efficient energy usage demands to have a higher proportion of renewable energy in the energy market. Since heat pumps are considered to be one of the most efficient heating and cooling systems, they will play an important role in the energy consumption reduction in buildings aimed to meet the target of nearly zero energy buildings set out in the EU Directive 2010/31/EU. Unfortunately, the declared heat pump Coefficient of Performance (COP) corresponds to a certain outdoor temperature (+7 °C), therefore different climate conditions, building characteristics and settings result in different COP values during the year. The aim of this research is to investigate the Seasonal Performance factor (SPF) values of air-to-water heat pump which better characterize the effectiveness of heat pump in a longer selected period of time, especially during the winter season, in different types of residential buildings in Latvian climate conditions. Latvia has four pronounced seasons of near-equal length. Winter starts in mid-December and lasts until mid-March. Latvia is characterized by cold, maritime climate (duration of the average heating period being 203 days, the average outdoor air temperature during the heating period being 0.0 °C, the coldest five-day average temperature being −20.7 °C, the average annual air temperature being +6.2 °C, the daily average relative humidity being 79 %). The first part of this research consists of operational air-towater heat pump energy performance monitoring in different residential buildings during the winter season. The second part of the research takes place under natural conditions in an experimental construction stand which is located in an urban environment in Riga, Latvia. The inner area of this test stand, where air-to-water heat pump performance is analyzed, is 9 m2. The ceiling height is 3 m, all external wall constructions (U = 0.16 W/(m2K)) have ventilated facades. To calculate SPF, the experimental stand is equipped with sensors which provide measurements for electricity consumption and gained heat energy.

Air-water heat pump applied as water boiler in single-family house, coefficient of performance analysis under the real conditions

2018 ◽  
Vol 3 (2) ◽  
pp. 58-61
Author(s):  
Agnieszka Lisowska-Lis ◽  
Robert Leszczyński
Keyword(s):  
Heat Source ◽  
Heat Pump ◽  
Air Temperature ◽  
Electrical Energy ◽  
Coefficient Of Performance ◽  
Single Family ◽  
Pump System ◽  
Heat Pump System ◽  
System Temperature ◽  
Family House

The subject of the research was an air-water heat pump, model PCUW 2.5kW from HEWALEX, installed in a single-family house. The pump is only used for heating water. The research was carried out from 25-08-2017 to 18-09-2017 in the village of Zborowice, in Malopolska region, Poland. The data were recorded from the heat pump system: temperature of the lower heat source (external air), temperature of the upper heat source (water temperature in the tank), time of heat pump was calculated during the analysed cycle of work and electrical energy consumption. The Coefficient Of Performance (COP) of the analysed air-water heat pump was determined. The analysis of the results was carried out using the MATLAB and EXCEL statistical tools. The correlation between COP coefficient and external air temperature is strong: 0.67.

scholarly journals Thermodynamic analysis on an instantaneous water heating system of shower wastewater source heat pump

2017 ◽  
Vol 8 (3) ◽  
pp. 404-411 ◽  
Author(s):  
Yuguo Wu ◽  
Yake Jiang ◽  
Bo Gao ◽  
Zhigang Liu ◽  
Jing Liu
Keyword(s):  
Heat Transfer ◽  
Energy Consumption ◽  
Heat Pump ◽  
Water Reuse ◽  
Heating System ◽  
Water Systems ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Heat Transfer Area ◽  
Discharge Pressure

Abstract Water reuse and desalination systems are energy intensive processes, and their increasing use is leading energy consumption within water systems to be an increasingly important issue. Shower wastewater contains large amounts of heat, so there is an opportunity to recover energy from shower water to offset energy consumption elsewhere in water systems. This paper found ways to increase the output of hot water and lower the energy consumption by establishing a thermodynamic model of an instantaneous wastewater source heat pump. The system proved to be very effective, the heating COP (coefficient of performance) can reach 3.3 even in the winter. Under the conditions of limited heat transfer area, reducing the suction pressure of a compressor is a more feasible way to increase the hot water output to meet the needs of users rather than increasing the discharge pressure. Besides, increasing the heat transfer area of the evaporator is a more effective option. When the heat transfer area of evaporator varies from 0.5 to 1.0 square meters, a notable change is that the heating COP increases from 3.283 to 3.936. The heating COP in a system with a recuperator can reach 5.672, almost double that compared to the original systems.

scholarly journals Heat Pump Water Heater For Cold Climate – Canada

2021 ◽  
Author(s):  
Afarin Amirirad
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Residential Buildings ◽  
Minimum Energy ◽  
Cold Climate ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Water Heater ◽  
Domestic Hot Water ◽  
Heat Pump Water Heater

Considering the large energy consumption of conventional water heaters in residential buildings, the performance of a new type of water heater has been characterized through conducting experiments and numerical modelling. The specific water heater investigated in this work benefits from heat absorption from the indoor air, denoted as the air source heat pump water heater (ASHPWH), and is located in the Archetype Sustainable Twin House B in Toronto. The experiments have been conducted under three different indoor conditions associated with temperature and humidity. The coefficient of performance (COP), which quantifies the ratio of heating capacity to the consumed power of ASHPWH, ranges between 1.5 and 5, depending on the indoor dry bulb and water inlet temperatures. A TRNSYS model of ASHPWH has been constructed based on the obtained experimental results and has subsequently been integrated with a TRNSYS model of the Archetype Sustainable House (ASH). The numerical results were verified with the experimental data. The model results suggests that after employing ASHPWH, the domestic hot water energy consumption reduces by 60.3% and 53.2% compared to the electric water heater in summer and winter respectively. Due to the energy absorption of ASHPWH from the indoor environment, the heating load of the ASH house increases while its cooling load decreases. Furthermore, the annual electricity consumption of the ASH house due to the required heating and cooling as well as the domestic hot water demand is reduced by 21.3%. Finally, as a consequence of employing ASHPWH, the energy cost and GHG emission were reduced respectively by 22% and 21.7%. By investigating the system in four other Canadian cities, it appears that Vancouver and Edmonton would have the maximum and minimum energy savings respectively.

scholarly journals Heat Pump Water Heater For Cold Climate – Canada

2021 ◽  
Author(s):  
Afarin Amirirad
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Residential Buildings ◽  
Minimum Energy ◽  
Cold Climate ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Water Heater ◽  
Domestic Hot Water ◽  
Heat Pump Water Heater

Considering the large energy consumption of conventional water heaters in residential buildings, the performance of a new type of water heater has been characterized through conducting experiments and numerical modelling. The specific water heater investigated in this work benefits from heat absorption from the indoor air, denoted as the air source heat pump water heater (ASHPWH), and is located in the Archetype Sustainable Twin House B in Toronto. The experiments have been conducted under three different indoor conditions associated with temperature and humidity. The coefficient of performance (COP), which quantifies the ratio of heating capacity to the consumed power of ASHPWH, ranges between 1.5 and 5, depending on the indoor dry bulb and water inlet temperatures. A TRNSYS model of ASHPWH has been constructed based on the obtained experimental results and has subsequently been integrated with a TRNSYS model of the Archetype Sustainable House (ASH). The numerical results were verified with the experimental data. The model results suggests that after employing ASHPWH, the domestic hot water energy consumption reduces by 60.3% and 53.2% compared to the electric water heater in summer and winter respectively. Due to the energy absorption of ASHPWH from the indoor environment, the heating load of the ASH house increases while its cooling load decreases. Furthermore, the annual electricity consumption of the ASH house due to the required heating and cooling as well as the domestic hot water demand is reduced by 21.3%. Finally, as a consequence of employing ASHPWH, the energy cost and GHG emission were reduced respectively by 22% and 21.7%. By investigating the system in four other Canadian cities, it appears that Vancouver and Edmonton would have the maximum and minimum energy savings respectively.

scholarly journals The Performance of an ASHP System Using Waste Air to Recover Heat Energy in a Subway System

2019 ◽  
Vol 1 (1) ◽  
pp. 154-163 ◽  
Author(s):  
Konstantinos Ninikas ◽  
Nicholas Hytiris ◽  
Rohinton Emmanuel ◽  
Bjorn Aaen
Keyword(s):  
Heat Pump ◽  
Air Temperature ◽  
Short Communication ◽  
Heat Energy ◽  
Coefficient Of Performance ◽  
Air Source Heat Pump ◽  
Lessons Learnt ◽  
Waste Air ◽  
Subway System

In this short communication, we demonstrate that the performance of a typical air source heat pump (ASHP), exploiting a relatively stable air temperature within a subway environment, is high, even during the peak heating months. After a nine-month operational run, the coefficient of performance is demonstrated to be 3.5. The design and installation difficulties are stated together with the lessons learnt following this trial. The actual energy and carbon savings are discussed.

Sign in / Sign up

Export Citation Format

Share Document