Numerical Simulation of Operating Parameters of the Ground Source Heat Pump

Due to the growing demand for new ecological, low-emission heat sources, there is a need to develop new tools for simulating the operating parameters and costs of the implemented solutions. The article analyses the existing solutions for the simulation of heat pump operation parameters, describes the requirements for a modern building—nZEB and proposes a simulation tool based on thermodynamic parameters of the refrigerant. The script allows for deriving simple linear equations that can be used for the overall simulation of a system in which the heat pump is a key part and the efficiency of the entire system depends on its performance. The developed numerical script allows for reproducing the Linde refrigeration cycle and the parameters of its characteristic points. To calibrate the simulation, historical data obtained from the SOPSAR system were used. These data were pre-cleaned (peaks and other obvious measurement errors were removed). The obtained numerical model in combination with ground and air temperatures, anticipated hot water consumption and energy losses of the building can be used to simulate the annual performance and energy consumption of the heat pump. The obtained linear models have an RSMD error of 8% compared to historical data from SOPSAR system for all sets of simulated temperatures.

Optimal Power Dispatch in Energy Systems Considering Grid Constraints

As a consequence of the increasing share of renewable energies and sector coupling technologies, new approaches are needed for the study, planning, and control of modern energy systems. Such new structures may add extra stress to the electric grid, as is the case with heat pumps and electrical vehicles. Therefore, the optimal performance of the system must be estimated considering the constraints imposed by the different sectors. In this research, an energy system dispatch optimization model is employed. It includes an iterative approach for generating grid constraints, which is decoupled from the linear unit commitment problem. The dispatch of all energy carriers in the system is optimized while considering the physical electrical grid limits. From the considered scenarios, it was found that in a typical German neighborhood with 150 households, a PV penetration of ∼5 kWp per household can lead to curtailment of ∼60 MWh per year due to line loading. Furthermore, the proposed method eliminates grid violations due to the addition of new sectors and reduces the energy curtailment up to 45%. With the optimization of the heat pump operation, an increase of 7% of the self-consumption was achieved with similar results for the combination of battery systems and electrical vehicles. In conclusion, a safe and optimal operation of a complex energy system is fulfilled. Efficient control strategies and more accurate plant sizing could be derived from this work.

Feasibility Study of long term Dual Tank PV/T Indirect Parallel Solar Assisted Heat Pump systems

A novel dual tank PV/T indirect parallel solar assisted heat pump system (DTPV/T-ISAHP) was investigated in this paper, which filled a gap in the literature. Furthermore, a long-term performance study analysis was performed under Tunisian climate to offset domestic electric and hot water loads. Optimal operations of such a system are achieved based on a simplified mathematical model. Results showed that the average thermal and electric energy efficiency is about 39.65% and 11.38%, respectively. Results revealed that the increase in solar radiation results in an improvement of the system's thermal-based COP efficiency coefficient reaching 4.49 at 893 W/m2. PV/T average electrical energy output is found to 0.68 kWh/m2/day with an annual average of 177.42 kWh/m2, which leads to an annual electricity surplus of about 5.83%. A reversible heat pump operation seemed more advantageous especially in the summer months, reducing yearly electric demand by about 84.57%. An economic analysis is undertaken and a payback period of about 12.7 years is found. The current study provided a framework for assessing such a system's behavior and providing useful flexibility to achieve the best possible system performance.

ANALYSIS OF THE HEAT PUMP OPERATION IN THE LOW-TEMPERATURE RECTIFICATION SYSTEM OF PROPANE-BUTANE MIXTURE

The article presents the results of the analysis of the operation of a heat pump in the system of low-temperature rectification of a propane-butane mixture. High-purity propane is obtained from a propane-butane mixture. A "rectification column-heat pump" system is proposed, which transforms the heat removed during the cooling of the component in the upper part of the column into heat absorbed during heating of the bottoms. In accordance with the energy balance of the system, it has been established that part of the heat pump condensation is not used in the distillation column, but is removed to the environment. The heat pump flow diagram contains one evaporator and two condensers. The operation of the heat pump is evaluated from the standpoint of thermodynamics – by the method of energy analysis of the cycle with R134 and R290 working substances, It has been established that the low thermodynamic efficiency of the heat pump is determined by external irreversible losses in the condensers and the evaporator The advantages of R290 as a working substance of the heat pump have been proved and the required theoretical volumetric capacity of the compressor has been determined.

Comparison of Flexibility Factors and Introduction of A Flexibility Classification Using Advanced Heat Pump Control

With the increasing use of renewable energy, the energy flexibility of buildings becomes increasingly important regarding grid support. Therefore, there is a need to describe this flexibility in a concise manner. For the characterization of building energy flexibility, flexibility factors can be used. The comparison of a selection of existing flexibility factors shows that they are not easy to use or understand for designers and users. A simplification is necessary. The aim of this study is to introduce a flexibility classification that is easy to understand and shows in an easy way if a building already uses the lowest energy cost level or if further improvement is possible. The classification expresses the annual energy costs in colored classes: green (class A) for lowest up to red (class D) for highest level. Basically, the flexibility classes can be derived for any metric of interest, in this paper examples are shown for energy costs and CO2eq emissions. The results given are based on the simulation of load management scenarios with different penalty signals applied for the heat pump operation of a residential building.

Artificial Lift Rigless Opportunity to Re-Activate the Inactive Wells Inventory an a Middle East Mega-Field After a Successful Pilot of a Best Practices and New Technology With Jet Pump

A Gulf oil operation company has been working to evaluate a rigless method of Artificial Lift System (ALS) suitable for its current assets and any future needs on ALS to minimize the impact of deferred production, and having the flexibility to bringing back the inactive string to production and act as a sustained production lift method. This paper describes a comprehensive study of the main objectives for a rigless Artificial Lift trial. The Rigless Jet Pump system was selected as one of the ALS fast implementation methods to activate the inactive wells. The trial was conducted in two inactive wells; across two different mega-fields, enabling both wells to produce stably and continuously with an average production rate of 650 BOPD. A thorough assessment was performed and the Rigless Jet Pump System was declared as a successful pilot providing confidence to scale up across all the company fields. The scale-up plans it will include 10 systems that can be rotated and applied where needed across all company fields. The trial implementation of the Rigless Jet Pump was evaluated based on supply and the connectivity in the field. This includes equipment mobilization (from the call-out time), availability of the field resources, the installation job, and up to the Surface Equipment connectivity plan. The evaluation also closely monitored the subsequence rig-up procedure and rigless deployment of the downhole equipment which was designed for installation straddled across an existing gas lift side pocket mandrel. Once surface and subsurface installation was completed, the wells were put on production to reactivate the inactive strings. Both wells were tested to confirm the achievement of a minimum of 80% of the designed production rates. The performance of the rigless activation of inactive wells using a jet pump has been proven successful. Both wells showed promising results while jet pump operation confirming a profitable alternative to accelerate production across fields toward achieving production mandates. The performance of the system delivered the Efficiency and Safety (HSE & Integrity) expected as part of the project KPI's. This novel practice for the Jet Pump System is linked to the rigless deployment and retrieval mechanism with topside equipment skid mounted for easy movement to other wells. This gives to the oil field operators an alternative and competitive edge over other modes of lift that required a workover program. The rigless method can be adapted to the existing in-active wells with SPM (side Pocket Mandrels) or without; by a tubing punch after a comprehensive integrity evaluation.

Hydraulic calculation of the fire extinguishing system of port facilities

Цель статьи – разработать алгоритм расчёта гидравлических характеристик системы пожаротушения для портовых сооружений. В системе пожаротушения имеется погружной насос, трубопроводы, предназначенные для транспортировки воды от места ее забора, до места возможного возгорания. Использован насос UGP-M-1210-04. Задачи исследования: анализ результатов испытаний; получение эмпирических зависимостей показателей работы насоса от его производительности, исследования работы насоса в сети. Проведены расчеты скорости истекающей струи и полной реактивной силы в рабочей точке насосной установки. Исследовано влияние скорости на реактивную силу. Анализ результатов показывает, что точность расчетов приемлема для инженерных расчетов. Полученный алгоритм расчета может быть использован при проектировании систем тушения пожаров в портовых сооружениях. The purpose of the article is to develop an algorithm for calculating the hydraulic characteristics of a fire extinguishing system for port facilities. The fire extinguishing system has a submersible pump, pipelines intended for transporting water from the place of its intake to the place of possible ignition. The UGP-M-1210-04 pump is used. Research objectives: analysis of test results; obtaining empirical dependencies of pump performance indicators on its performance, research of pump operation in the network. Calculations of the velocity of the expiring jet and the total reactive force at the working point of the pumping unit are carried out. The effect of velocity on the reactive force is investigated. Analysis of the results shows that the accuracy of calculations is acceptable for engineering calculations. The resulting calculation algorithm can be used in the design of fire extinguishing systems in port facilities.

Solar Power System Design Applications for Pool Water Pump Operation at Tourist Accomodation

Utilization of solar energy in Indonesia has begun to bloom. This is due to the fact that Indonesia is located at the equator where the sun is exposed all year round and is a very environmentally friendly energy. Based on this, solar energy is used as an option to meet electricity needs by using a photovoltaic (PV) system. The use of a photovoltaic system as a power provider to operate a pool water pump at a villa in Bali is an example of the application of a photovoltaic system. In this study, A Seri and Parallel photovoltaic arrays were used with a panel system that was integrated with PLN electricity. The angle of inclination and direction of placement chosen in this study is 15° with facing north, which refers to research that, has been done previously. PV designs and a series of control panels that can be accessed via the internet will be described as well. The aim in this research is investigate how photovoltaic design used as a solar power plant which applied to the module can be runing the pool water pump in the villa or tourist accommodation.

Waste Heat Recovery by Air-to-Water Heat Pump from Exhausted Ventilating Air for Heating of Multi-Family Residential Buildings

The paper presents an analysis of the application of an air-to-water electric compressor heat pump (AWHP) for the recovery of waste heat from the exhaust air in a typical multifamily residential building and the use of this heat for space heating, as well as the impact of this solution on the building energy performance (the PPR index). Simulations were performed in TRNSYS for five locations in Poland (Koszalin, Wrocław, Lublin, Białystok, Suwałki), for various heating system parameters (80/60 °C, 75/65 °C, 70/50 °C, 55/45 °C, 35/28 °C), for various temperature limitations of heat pump operation. It was shown that the analyzed system has great potential from an energy and environmental point of view. It can provide significant benefits in terms of the energy performance of the building, depending on the system parameters. The results show that the most energy-efficient system is the one with the lowest heating system temperatures. Moreover, implementing a temperature limitation on the heat pump operation improves its efficiency, but the higher the design parameters of the heating installation and the lower the limitation, the lower the heat pump contribution, and the higher the SCOP and the PPR. The energy effect is also influenced by location, but its scale depends on the parameters of the heating system and the temperature limitation of the heat pump’s operation. It is more significant for lower heating system parameters. This system enables the possibility of further reducing the demand for nonrenewable primary energy by powering the heat pump with photovoltaic cells.

Physical Testing of a High-Speed Helico-Axial Pump for High-GVF Operation

High-speed rotordynamic pump operation for downhole or surface production is required and also beneficial to handle very high gas volume fraction (GVF) flows. Operating speeds of these pumps can be in excess of twice those of conventional pumps. This study presents results showing a high-speed helico-axial pump (HAP) can operate satisfactorily at intake GVFs up to 98%. The findings increase capabilities of field engineers and operators to boost and maximize production from high gas-content wells. The HAP tested had a housing outer diameter of 4.00-inch and operated at a rotational speed of 6000 revolutions per minutes (RPM). Air and water were the test fluids with the water volume flow rate held constant while the air volume flow rate was varied. The liquid and gas volume flow rates varied from 63 to 143 barrels per day (BPD), and 549 to 3238 BPD, respectively. Intake pressures varied from 14 to 76 psig, with average inlet temperature of 18°C. The corresponding discharge pressures and temperatures were recorded for each test point and observed for stable pump operation. The results showed that the HAP had stable operation during the tests for intake GVF range from 84% to 98%. Pump discharge pressures for this range of high intake GVF varied from 21 to 89 psig. The corresponding differential pressures across the HAP all had positive magnitudes indicating that at such high-speeds, the HAP was still able to add energy to the fluid even with the high gas content at intake. Analysis at fixed intake pressure with varying GVFs showed that the discharge-to-intake pressure ratio decreased with increasing intake GVF. For instance, at 33psig intake pressure, increasing the intake GVF from 84% to 94% decreased the discharge-to-intake pressure ratio from about 1.27 to 1.20, respectively. It was also observed that tightening the clearance between the impeller and diffuser of the HAP increased the discharge pressure compared to when the clearance was loose. Furthermore, ensuring the upstream flow is properly conditioned also improved the stable operation of the HAP. Overall and in conclusion, running a HAP at high speeds in addition to optimizing certain features of the HAP can result in stable pump operation and enhanced pressure boosting in high-GVF flows. This study mainly highlights the importance of operating HAPs at high speeds of up to 6000 RPM. Tightening clearances between rotordynamic components as well as tailored inlet flow conditioning are also additional features that enhance pressure boosting. This architecture opens up opportunities for field operators, and engineering personnel to maximize hydrocarbon production from their very high-gas content field assets, thereby increasing the economic bottomline for the stakeholders.