Solar water heating: From theory, application, marketing and research

Wang, Zhangyuan; Yang, Wansheng; Qiu, Feng; Zhang, Xiang-Mei; Zhao, Xudong

doi:10.1016/j.rser.2014.08.026

Cited by 140 publications

(43 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Heating accounts for 40 to 50% of the global energy demand and 75% of the energy demand within the buildings sector (15). Urban solar thermal energy, specifically for space and domestic water heating, has been an area of particular research interest.…”

Section: Solar Energymentioning

confidence: 99%

“…Urban solar thermal energy, specifically for space and domestic water heating, has been an area of particular research interest. With efficiencies up to 80% (15), solar hot-water systems offer a thermal power density up to 240 W t /m 2 under optimal conditions (W t , watt-thermal), whereas the global averaged thermal power density of solar heat collectors is 67 W t /m 2 (16). Because domestic solar hot-water heaters are low-cost and compact, one study showed that 84% of urban households in China could install the system on their rooftops (17).…”

Section: Solar Energymentioning

confidence: 99%

See 1 more Smart Citation

City-integrated renewable energy for urban sustainability

Kammen

Sunter

2016

Science

474

169

View full text Add to dashboard Cite

To prepare for an urban influx of 2.5 billion people by 2050, it is critical to create cities that are lowcarbon, resilient, and livable. Cities not only contribute to global climate change by emitting the majority of anthropogenic greenhouse gases but also are particularly vulnerable to the effects of climate change and extreme weather. We explore options for establishing sustainable energy systems by reducing energy consumption, particularly in the buildings and transportation sectors, and providing robust, decentralized, and renewable energy sources. Through technical advancements in power density, city-integrated renewable energy will be better suited to satisfy the high-energy demands of growing urban areas. Several economic, technical, behavioral, and political challenges need to be overcome for innovation to improve urban sustainability.S ince 2007, a greater percentage of the global population has been living in urban areas than in rural areas. Increased urbanization is expected to continue, with two-thirds of the world's population projected to live in urban areas by 2050, a net urban influx of 2.5 billion people (1). Cities today are generally not equipped to address dramatic urban growth and strain on existing infrastructure in a sustainable way, especially with respect to their energy systems.To be sustainable, cities must themselves, or in the resources that they command, become lowcarbon, resilient, and livable (2). Although there can be considerable variation in methods for evaluating the emissions footprint of cities (3), with 54% of the population living in urban areas, it is estimated that cities are currently responsible for 60 to 70% of anthropogenic greenhouse gas emissions (4). The two main strategies for transitioning to a low-carbon city are to shift from fossil fuels to cleaner energy sources and to reduce urban energy consumption levels. The low-carbon transition can be accomplished through energyefficiency measures, behavioral interventions, and incorporating carbon sinks such as urban parks. Cities and their energy systems should also be resilient to natural and human-made threats (2). The energy systems of cities are increasingly vulnerable to the effects of climate change and extreme weather, including storms, flooding, and sea-level rise, and also to natural and humaninduced disasters. In addition, urban energy systems directly affect the well-being and happiness of urban inhabitants. Health conditions, economic competitiveness, cultural appeal, and social, gender, and racial equality are influenced by high-energy sectors such as transportation, food production, and water quality.Here we evaluate some of the more promising recent technological advancements that could help urban areas become sustainable cities. Many opportunities exist, but focusing on city-integrated renewable energy-defined as distributed, nonfossil fuel energy generated locally in urban areas-has the potential to help cities meet several sustainability needs. Many of these renewable sources increase regional ener...

show abstract

Section: Solar Energymentioning

confidence: 99%

Section: Solar Energymentioning

confidence: 99%

City-integrated renewable energy for urban sustainability

Kammen

Sunter

2016

Science

474

169

View full text Add to dashboard Cite

show abstract

Section: ) Economic Factormentioning

confidence: 99%

“…The financial support by the government bodies in term of subsidy is considered necessary to encourage user. The subsidy scheme for alternative water heating technology is promoted in many countries such as Germany, Austria, Sweden, Australia and Netherlands [39].The government of Thailand also has many projects for supporting their investment such as ESCO (Energy Service Company) Fund and Revolving Fund. Thai government also set the project that called "Cost Base" in 2012 to encourage people use the electric appliance with high performance and energy saving which can discount tax up to 25% of their appliance price.…”

mentioning

confidence: 99%

A Case Study of Success in Phasing out Policy of Instantaneous Water Heater in Australia and Feasibility in Thailand

Jingjit¹,

Techato²

2017

IJTEF

View full text Add to dashboard Cite

Abstract-This paper discusses the original, successful and effect of phasing out policy of instantaneous water heater in Australia. This can be applied for Thailand in order to phase out instantaneous water heater as a milestone. Hence, this work focuses on shifting from instantaneous water heater to heat pump and solar water heater. Thailand is suitable for these technologies because the high level of solar radiation is free from the sun. Many large buildings normally use heat pump but not popular in household. The important factors for consumers in Thailand are education and realization of energy saving and global warming issue. The knowledge of technician and consultant have to be developed for the new technologies. Phasing out policy of instantaneous water heater can be done under the supporting of Thai government, especially in term of subsidy for the high investment cost.Index Terms-Phasing out policy, instantaneous water heater, Energy saving, Conservative energy. I. INTRODUCTIONA common interesting topic presently regarding environmental issue is the global warming under Kyoto Protocol. Many approaches are announced in order to reduce greenhouse gas such as carbon footprint, carbon credit, green label, energy efficiency labels and etc. One of the most popular campaign is to reduce the electricity consumption. Especially, the old design of the electric devices with high power was obligated to be phased out and replaced by the new technologies such as:1) "China Energy-Efficiency Refrigerator Project" from Dec 1999 to June 2006 that the old technology was replaced by the new one with 2 times-lower energy consumption than the existing [1].2) "Lamp Phasing Out Legislations" from Jan 2012 to July 2014 by stopping the manufacturer for 100 & 75 watt incandescent and T12 Linear Fluorescent Lamps and Standard Halogen PAR Lamps in U.S. [2].Australia endorsed the Kyoto Protocol in December 2007 to United Nations Framework Convention on Climate Change. From the UN Climate change conference (COP18 CMP8) on 8 December 2012 at Doha, Qatar. Most of Annex I countries Manuscript received October 27, 2016; revised February 5, 2017 -REDP (The Renewable Energy Development Plan), to use renewable energy 20.3% of total energy in 2022 [7].-AEDP (The Alternative Energy Development Plan), to use alternative energy 30% which can reduce energy from fossil fuel 39,388 ktoe and 140 million tons CO 2 [8].-EEDP (The Thailand 20 -Year Energy Efficiency Development Plan), to reduce energy intensity 25% in 2030 baseline 2005 [9]. II. AUSTRALIA ISSUE A. Greenhouse Gas EmissionElectric storage water heating emits almost a quarter of greenhouse gas from Australian households (refer with: Fig. 1). Electric hot water system produces around four tons of greenhouse gases every year. That is equivalent to the running an average 10 cars for a year [10]. Over 80% of electricity is generated from coal, 15% from natural gas and only 3% from renewables. Hence, an alternative water heating options such as heat pump, natural gas and solar collector can ...

show abstract

“…Glycol-water mixtures are also used for solar water heating applications when the operating temperatures of solar heaters rises beyond the low-temperaturecollector region to low-medium-temperature collectors i.e. beyond 100°C [49][50][51].…”

Section: Page 4 Of 11mentioning

confidence: 99%

Recent Developments in Heat Transfer Fluids Used for Solar Thermal Energy Applications

Srivastva¹,

Malhotra²,

Sc³

2015

J Fundam Renewable Energy Appl

View full text Add to dashboard Cite

Solar thermal collectors are emerging as a prime mode of harnessing the solar radiations for generation of alternate energy. Heat transfer fluids (HTFs) are employed for transferring and utilizing the solar heat collected via solar thermal energy collectors. Solar thermal collectors are commonly categorized into low temperature collectors, medium temperature collectors and high temperature collectors. Low temperature solar collectors use phase changing refrigerants and water as heat transfer fluids. Degrading water quality in certain geographic locations and high freezing point is hampering its suitability and hence use of water-glycol mixtures as well as water-based nano fluids are gaining momentum in low temperature solar collector applications. Hydrocarbons like propane, pentane and butane are also used as refrigerants in many cases. HTFs used in medium temperature solar collectors include water, waterglycol mixtures -the emerging "green glycol" i.e., trimethylene glycol and also a whole range of naturally occurring hydrocarbon oils in various compositions such as aromatic oils, naphthenic oils and paraffinic oils in their increasing order of operating temperatures. In some cases, semi-synthetic heat transfer oils have also been reported to be used. HTFs for high temperature solar collectors are a high priority area and extensive investigations and developments are occurring globally. In this category, wide range of molecules starting from water in direct steam generation, air, synthetic hydrocarbon oils, nanofluid compositions, molten salts, molten metals, dense suspension of solid silicon carbide particles etc., are being explored and employed. Among these, synthetic hydrocarbon oils are used as a fluid of choice in majority of high temperature solar collector applications while other HTFs are being used with varying degree of experimental maturity and commercial viability -for maximizing their benefits and minimizing their disadvantages. Present paper reviews the recent developments taking place in the area of heat transfer fluids for harnessing solar thermal energy. Refrigerants/phase changing materials: These are low boiling point but high heat capacity substances used in the solar collectors to transfer heat in applications like solar space cooling and heating, refrigerators, air conditioning, etc [7]. These materials absorb heat from the solar collectors, produce work either by expanding in a turbo-generator of a vapor compression cycle or by dissociating the refrigerant from its absorbent in a vapor absorption cycle [8]. In some of the relatively high temperature applications, higher boiling point refrigerants are used as indirect heat transfer fluids, wherein the heat collected from the solar collectors is transferred to another fluid like water from where the refrigerants pick-up heat to do the required work in the turbo-generators [9,10]. Recent Developments in Heat Transfer

show abstract

Solar water heating: From theory, application, marketing and research

Cited by 140 publications

References 50 publications

City-integrated renewable energy for urban sustainability

City-integrated renewable energy for urban sustainability

A Case Study of Success in Phasing out Policy of Instantaneous Water Heater in Australia and Feasibility in Thailand

Recent Developments in Heat Transfer Fluids Used for Solar Thermal Energy Applications

Contact Info

Product

Resources

About