• Energy Research

The heating and cooling industry underpins everything we do, e.g., manufacturing, commercial and residential applications. Many of these applications invariably use mechanical refrigeration technologies, consequently contributing significantly to the environmental impacts of the refrigeration, air conditioning, and heat pump (RACHP) industry both through direct and indirect emissions of CO2. To reduce these emissions, research and development worldwide aim to improve the performance of conventional systems and the development of new refrigeration technologies of potentially much lower environmental impacts. As we transition to a low carbon economy, there are sizable environmental and economic benefits from developing and using efficient, innovative, low carbon heating and cooling technologies that reduce energy use and carbon emissions. This paper provides an up-to-date and comprehensive critical review and evaluation of recent advances in emerging alternative heating and cooling technologies that have the potential to reduce the environmental impacts of refrigeration in the RACHP sector. The paper highlights the basic working principle of operation, its main applications, the challenges and opportunities in penetrating the market. The paper also highlights further research and development needed to accelerate the development and adoption of these alternative refrigeration technologies by the sector. Most of the technologies reviewed have a Technology Readiness Level (TRL) of 3–4, except electrocaloric technology which is less ready compared to its counterparts with a TRL of 1–2 at this stage. Furthermore, most technologies have capacities ranging between a few kilowatts to a maximum of 7 kW with a coefficient of performance COP between 1 and 10 reported in the literature.

This paper shows the results of a novel research conducted with the overall aim of developing a system that can provide continuous desalination. Productivity enhancement of solar stills is regarded as the main purpose of the investigators in desalination field. This paper represents the experimental results in a new approach of paraffin + graphene oxide nanoparticles mixture. The paraffin mixture in a semicircular, triangular and rectangular absorber with paraffin +graphene oxide of 0.1, 0.3 and 0.5 wt% has been investigated. The finding indicated that for all absorbers, the use of paraffin + graphene oxide in higher weight fractions enhances daily freshwater production. The results showed that the thermal performances are greater applying graphene oxide + paraffin of 0.5%wt with semicircular absorber compared to triangular and rectangular absorber. The achievement of the present paper can be implemented to design more efficient absorbers for solar still parts.

© 2021 Elsevier Ltd Approximately half of all energy consumed is used for generating heat and hot water in the UK, meanwhile, space heating and hot water consist of about 21% of greenhouse gas emissions. One pathway of decarbonizing heat is electrification of heat, the requirement of electricity is then met through smart grid and demand side response management. A new method for electrifying heat through a balanced energy network (BEN) system, which is situated in central campus of London South Bank University, has been presented. The validations of BEN model are performed against historic measurement data and manufacturer performance data. BEN system performance is then predicted and evaluated through investigating the effects of BEN and building internal factors including system operation mode, thermal storage, indoor set-point temperature, and COP of heat pump. Several key results were drawn as follows: (1) Carbon emissions from building energy consumption mainly depend on operation mode and thermal storage capacity of BEN system, actual heat demand in buildings and carbon emission factor as a function of time; (2) Energy consumption and costs and its carbon emissions will nonlinearly increase with the increasing of indoor set-point temperature; (3) In January (the coldest month of the year), the heating consumption for operating BEN system will be decreased by 77.9%/72.9% compared with historic monitoring data of 2014/2015; (4) For BEN system, the usage, costs and carbon emissions of electricity supplying to heat pump is an decreasing function of COP.

The widespread adoption of low GWP alternative refrigerants across Europe is critical to achieving long-term carbon reduction emissions from the Refrigeration, Air Conditioning and Heat Pump (RACHP) sector. The RACHP sector has been identified as being responsible for significant greenhouse gas emissions through direct emission (leakage of high GWP refrigerants) and indirect emissions (energy use). The changes to EU’s Fluorinated greenhouse gases (F-gas) regulation No 517/2014, which came to force since 1st January 2015, has enacted restrictions on the use of halocarbon refrigerants in certain applications with the intent of reducing the F-gas associated emissions in the EU region. There are currently inconsistent levels of knowledge and awareness of how alternative refrigerants can be sustainably procured and utilised. This paper provides an understanding of the needs for skills in some European countries, specifically covering the general overview of the “as installed“ RAC use, the current training provision, the potential use and status of alternative refrigerants and recommendations on procurement process. Furthermore, the paper discusses the availability of skills and existing training materials and template in specific European countries.

Abstract Current electricity distribution systems allow prosumers to sell their surplus electricity back to the Distributed Network Operator (DNO). The export tariffs at which these sell-backs take place are considerably lower than the feed-in tariffs, offering little incentive to prosumers to sell their surplus energy. A peer-to-peer (P2P) electricity market where consumers and prosumers can interact by selling and buying energy between them at a premium rate that is lower than the standard feed-in tariffs but higher than the export tariffs is proposed. Such a system was modelled to process transactions every 20 s, and a simulation tool was created to obtain the total daily money flows between a consumer-prosumer pair. The inclusion of a Distributed Storage System (DSS) is also considered in the modelled system and simulation. The simulation results showed that the inclusion of a DSS is always beneficial for all parties in economic terms: consumers could save up to 6.4 % on the cost of their electricity while prosumers could save up to 49.1 %. A DSS could generate an income flow for the DNO of up to 6.9p/day per each consumer-prosumer pair.