我国光伏发电有关问题研究

光伏发电在解决我国无电地区电力建设和电力规模的并网发电的市场中都将扮演重要的角色,应当予以高度重视。在原材料和市场两头在外的情况下,目前国内光伏发电产业有盲目增长的趋势。原材料短缺的问题有望在2～3年内得到解决,国内光伏市场的拉动是保证中国光伏产业健康发展的关键。无论是离网光伏电站的后期运行维护的问题,还是并网光伏发电市场拉动的问题,都有赖于《可再生能源法》的全面实施。     

光伏发电在我国电力能源结构中的战略地位和未来发展方向

保障能源和环境可持续发展,特别是保证一次能源的供给是我国面临的重大战略问题。可再生能源将逐步替代化石能源,成为人类可持续发展的能源。在可再生能源中,潜力最大的是太阳能,到本世纪中期太阳能将成为电力能源中的重要组成部分,而到本世纪末成为电力能源中的主要部分。我国拥有丰富的太阳能资源,是中华民族赖以生存的最宝贵的资源。光伏发电技术目前已经成熟,发展势头迅猛,正在努力突破高成本的制约瓶颈,有望在30年左右的时段内成为重要的电力能源之一。在今后10～20年,我国的光伏发电将主要应用于下述方面:农村离网供电,分布电源,大规模荒漠电站以及其它商业应用。国家应首先加强光伏发电各项能力建设,包括资源普查和评估、研发能力建设、培训体系建设、质量监督服务体系建设,并积极开展国际合作,引进技术、人才和资金,为我国光伏发电的健康、可持续发展奠定坚实的基础。     

Recent advances in alternative material photovoltaics

Abstract

Alternative material photovoltaics (PVs) have started gaining more attention recently. Although the field is not new, it just started growing a few years ago. The PV market has been dominated by various silicon technologies, besides a few other popular thin films, such as CdTe, copper–indium–galium–selenide varieties and some III–V materials. This has been reflected in research as well. Successful developments of efficient solar cells using alternative absorbers will significantly enrich the PV industry and reduce the market gap with other energy sources. Hence, in this review, recent advances and trends to develop PVs using alternative materials are presented and discussed. The focus will be mainly on binary as well as environmentally friendly compounds and thin film devices. Nonetheless, some other more complex materials and structures will be briefly addressed.     

Reliability based socio economic optimal renewable energy model for India

Renewable energy sources such as solar, wind and biomass have to play a vital role in the developing countries like India in order to meet the growing energy demand. In the last five years, some renewable energy sources had emerged as technically and economically viable alternatives in the energy sector, as a result, more ambitious plans for their dissemination were being launched. In this situation, development of an energy model exclusively for renewables will help in the allocation of appropriate renewable energy systems for different end-uses in the future. An attempt has been made to develop a reliability based socio economic optimal renewable energy model for India in the year 2020–2021. The effect of social acceptance variation in OREM model was analysed. The lighting end-use would be met by solar PV and biogas system to an extent of 0.5198×10¹⁵ kJ and 0.75×10¹⁵ kJ, respectively. Similarly, the renewable energy utilisation is found for other end-uses.     

中国光伏产业与太阳能热利用产业的发展模式比较

中国的太阳能光伏产业和太阳能热利用产业近年来都呈现出较快的发展趋势,但二者的发展特征却迥然不同。中国光伏产业虽然起步较晚,但增长速度快,从2003年开始年增长速度都超过100%,2007年成为世界第一大太阳能电池生产国;太阳能热利用产业在20世纪90年代就已形成相当大的规模,年增长速度一直保持在20%左右,2009年中国太阳能热水器产量和保有量分别达到4200×104m2和14500×104m2。中国太阳能热利用产业可谓一枝独秀,占世界总产量的一半以上,且在产业链各个环节发展比较平衡;而中国光伏产业并不具有绝对优势,特别是产业链上游发展比较滞后。太阳能热利用产业整体上是靠国内市场推动发展的,呈现出比较典型的内生型增长特征;而光伏产业表现为"两头在外"的特征,一方面关键的多晶硅材料进口量较大,另一方面产品主要以满足国际市场需求为主。中国太阳能发展政策的目标低、扶持力度小、实质性促进政策少,对太阳能产业发展的促进作用比较有限。此外,市场需求、技术、经济等也是影响产业发展的主要因素。为促进我国太阳能产业的健康发展,建议政府应提高太阳能利用的目标,加快相关立法工作,加大鼓励力度,加强财税支持,注重技术的研发,规范产业发展。     

PV solar electricity industry: Market growth and perspective

The photovoltaic (PV) solar electricity market has shown an impressive 33% growth per year since 1997 until today with market support programs as the main driving force. The rationales for this development and the future projections towards a 100 billion € industry in the 2020s, by then only driven by serving cost-competitively customer needs are described.The PV market, likely to have reached about 600 MW in the year 2003, is discussed according to its four major segments: consumer applications, remote industrial electrification, developing countries, and grid-connected systems. While in the past, consumer products and remote industrial applications used to be the main cause for turnover in PV, in recent years the driving forces are more pronounced in the grid-connected systems and by installations in developing countries. Examples illustrating the clear advantage of systems using PV over conventional systems based, e.g., on diesel generators in the rural and remote electrification sector are discussed. For the promotion of rural electrification combined with the creation of local business and employment, suitable measures are proposed in the context of the PV product value chain.The competitiveness of grid-connected systems is addressed, where electricity generating costs for PV are projected to start to compete with conventional utility peak power quite early between 2010 and 2020 if time-dependent electricity tariffs different for bulk and peak power are assumed. The most effective current-pulling force for grid-connected systems is found to be the German Renewable Energy (EEG) Feed-in Law where the customers are focusing on yield, performance, and long-life availability.The future growth in the above-defined four market segments are discussed and the importance of industry political actions in order to stimulate the markets either in grid-connected systems by feed-in tariff programs as well as for off-grid rural developing country applications by long-term financing schemes are pointed out.A technology roadmap is presented with special emphasis on the fact that different customer needs are best served with best-adopted technologies and not vice versa. The need for the third generation PV technologies, implying that so called first (c-Si-wafer)- and second (thin-film)- generation PV technologies will be overcome in a short to medium time scale, is obsolete; in contrast, the excellent scientific ideas developed within ‘Third generation’ concepts—like utilization of hot electrons, quantum wells and nanostructures—are shown to be part of ‘New Technologies’ opening new product ideas and additional market segments. The rationale for decreasing cost by increasing productivity for all technologies as well as the interpretation of price learning curves is presented.The role of PV in the future global energy supply chain is lined out. Due to a fast growing market driven by increasing widespread acceptance of PV, a substantial PV business and creation of employment in coming decades is expected. This in turn can provide solutions for nowadays global issues, such as a global energy justice by providing environmentally benign power to billions of people, who otherwise will lack energy solutions severely.     

Modeling and simulation of grid-connected photovoltaic energy conversion systems

Solar power generation using PV (photovoltaic) technology is a key but still evolving technology with the fastest growing renewable-based market worldwide in the last decade. In this sector with tremendous potential for energy security and economic development, grid-connected PV systems are becoming today the most important application of solar PV generation. Based on this trend, PV system designers require an accurate and reliable tool in order to predict the dynamic performance of grid-tied PV systems at any operating conditions. This will allow evaluating the impact of PV generation on the electricity grids. This paper presents a detailed characterization of the performance and dynamic behavior of a grid-connected PV energy conversion system. To this aim, a flexible and accurate PV simulation and evaluation tool (called PVSET 1.0) is developed. The PV system is modeled, simulated and validated under the MATLAB/Simulink environment. The accuracy of simulation results has been verified using a 250 Wp PV experimental set-up.     

A system dynamics approach for the photovoltaic energy market in Spain

The goal of this paper is to contribute to understanding the behaviour of the photovoltaic (PV) sector in Spain and its expectations under possible scenarios. Currently, PV solar energy is not a profitable sector by itself. Therefore, the Spanish government, like the governments of other countries, has stimulated investment with subsidies. The spectacular increase of PV facilities exceeded all forecasts and the government decided to curb the trend. The present hypothesis is that continuing with this support to PV energy, the technological advances and the economy generated from the production of panels would be able to make the sector profitable in the future without the necessity of subventions. Based on this hypothesis, a computer simulation model was built using the system dynamics methodology. To test its utility, the model was challenged to fit the historical data and to explore several futures over the next few years. The model allows an understanding of the sector's behaviour under the latest policies of the Spanish government, thus helping to design future public policies. The simulation results are different depending on the adopted policy and the scenario. Therefore, these factors will determine the success or failure of the investments in this type of energy.     

The Hong Kong schools solar education programme

The Hong Kong schools solar education programme brings together Government, its Design and Education sectors, an electricity utility, CLP RI, academic researchers (PV HKU Research Group) and construction professionals to implement a programme that provides hands-on experience, IT skills and problem-based learning opportunities for (all) HK primary and secondary school children. Intended to raise their awareness and real understanding of the contribution of renewable energy technologies to everyday life, the programme has a further objective to expand the experience of local construction professionals in RET installations. At the same time the programme aims to create the start-up market for new industries specialising in related technology components, boosting their commercialisation and reducing costs plus reviving HK's industry sector. It's ultimate goal is to reduce CO₂ emissions through setting the school target of 25% energy generation from RET technologies. BIPV installations are the initial technology. These are combined with a specially developed school BEMS and website-based monitoring system from which the first pilot school will be assessed. Mini-installations are to be funded and installed in all HK schools through the HK PV Consortium.     

Current situation and future perspectives of European natural gas sector

Gas market in Europe is experiencing a radical change for different reasons, partially determined and accelerated by economic downturn of the last period. In the past few years, many European countries adopted energy policies largely based on the utilization of natural gas. In fact, a sharp increase of the demand was observed and, at the same time, a lot of infrastructures were developed to assure the necessary supply. In the last few years, due to the economic downturn, natural gas demand decreased, causing a consistent oversupply on the market, which altered the consolidated dynamics of the sector. Understanding the changes currently under development in the European gas market is of paramount importance in order to design future strategies for the sector; in particular, it is necessary to understand if the present situation will cause a reshaping of the sector.     

Feasibility of the green energy production by hybrid solar + hydro power system in Europe and similar climate areas

This paper analyses the hybrid solar and hydro (SHE) system as a unique technological concept of the sustainable energy system that can provide continuous electric power and energy supply to its consumers and the possibilities of its implementation in Europe and areas with similar climate. The sustainability of such system is based on solar photovoltaic (PV) and hydroelectric (HE) energy as renewable energy sources (RES). For the purpose of connecting all relevant values into one integral SHE system, a mathematical model was developed for selecting the optimal size of the PV power plant as the key element for estimating the technological feasibility of the overall solution. Sensitivity analysis (parameter analysis) was made for the model, where local climate parameters were varied: solar radiation, air temperature, reservoir volume, total head, precipitation, evaporation and natural water inflow. It has been established that, apart from total head (which is to be expected), solar radiation, hydro accumulation size and natural water inflow have the biggest effect on the calculated power of the PV power plant. The obtained results clearly show a wide range of implementation of the new energy source (SHE system), i.e. from relatively cold climates to those abundant in solar energy, but also with relatively small quantity of water, because it only recirculates within the system. All this points to the necessity for further development of hybrid systems (RES + HE systems) and to the fact that they could play an important role in achieving climate objectives.     

Grid electrification challenges, photovoltaic electrification progress and energy sustainability in Lesotho

Lesotho's energy profile is characterized by a predominance of traditional biomass energy to meet the energy needs of the rural households and a heavy dependence on imported petroleum for the modern economic sector needs. As a result, the country faces challenges related to unsustainable use of traditional forms of biomass and exposure to high and unstable oil import prices. There are relatively abundant renewable energy resources in the form of hydro, solar and wind. The average daily solar radiation in Lesotho varies between 4.5 and 6.5 kWh/m², with some areas in the South West averaging over 7 kWh/m²/day. Under the UNDP/GEF-supported Lesotho Renewable Energy-Based Rural Electrification (LREBRE) Project, a total of 5000 solar home systems (SHS) will be installed by 2012. Since the start of the project, a total of 1537 SHS with a capacity of 65 W have been installed, and an estimated 500 SHS have also been independently installed as a result of the project's influence. This paper examines the role of PV technologies in the sustainable development process, with particular reference to UNDP/GEF-LREBRE Lesotho PV project, and the extent to which this project is impacting on the PV industry. The paper also analyses national grid electrification and energy provision in rural areas and shows that the problem of rural electrification could be tackled by conventional and non-conventional means.     

Technical and economical system comparison of photovoltaic and concentrating solar thermal power systems depending on annual global irradiation

Concentrating solar thermal power and photovoltaics are two major technologies for converting sunlight to electricity. Variations of the annual solar irradiation depending on the site influence their annual efficiency, specific output and electricity generation cost. Detailed technical and economical analyses performed with computer simulations point out differences of solar thermal parabolic trough power plants, non-tracked and two-axis-tracked PV systems. Therefore, 61 sites in Europe and North Africa covering a global annual irradiation range from 923 to 2438 kW h/m² a have been examined. Simulation results are usable irradiation by the systems, specific annual system output and levelled electricity cost. Cost assumptions are made for today's cost and expected cost in 10 years considering different progress ratios. This will lead to a cost reduction by 50% for PV systems and by 40% for solar thermal power plants. The simulation results show where are optimal regions for installing solar thermal trough and tracked PV systems in comparison to non-tracked PV. For low irradiation values the annual output of solar thermal systems is much lower than of PV systems. On the other hand, for high irradiations solar thermal systems provide the best-cost solution even when considering higher cost reduction factors for PV in the next decade. Electricity generation cost much below 10 Eurocents per kW h for solar thermal systems and about 12 Eurocents/kW h for PV can be expected in 10 years in North Africa.     

The potential and economic viability of solar photovoltaic power in Ghana

In this study, the potentiality and economic viability of solar photovoltaic (PV) in Ghana was assessed using RETScreen software. 5 MW of grid-connected solar PV power system using SunPower SPR-320E-WHT-D PV module can be harnessed from Navrongo, Bawku, Wa, Tema, Bolgatanga, Axim, Salaga, Kintampo, Kete Krachi, Tamale, Hohoe, Koforidua, Ejura, Takoradi, Bole, Sunyani, Bibiani, Cape coast, Prestea, and Akuse, which requires US$17,752,179 of investment capital and 25,313 m² of land for PV installation. The potential of 5 MW grid-connected PV development for Accra, Kumasi, Wenchi, and Tafo are limited. However, there are solar PV energy potentials for low-capacity PV modules for these locations. Investing in solar photovoltaic technology is capital intensive in a developing country like Ghana. However, Government’s effort to provide incentives like subsidies and creating the economic environment for private sector investment will boost investment possibilities of renewable energy in Ghana, which can help in curbing the recent power outages and load shedding, thereby increasing productivity and economic resilience.     

Life cycle impacts and costs of photovoltaic systems: Current state of the art and future outlooks

The photovoltaic energy sector is rapidly expanding and technological specification for PV has improved dramatically in the last two decades. This paper sketches the current state of the art and drafts three alternative scenarios for the future, in terms of costs, market penetration and environmental performance. According to these scenarios, if economic incentives are supported long enough into the next ten to twenty years, PV looks set for a rosy future, and is likely to play a significant role in the future energy mix, while at the same time contributing to reduce the environmental impact of electricity supply.     

Advancements in the United States Photovoltaic Program

The major trends in PV technologies, applications and markets show promise for the future of renewable energy. The 30% growth projected for PV shipments in 1998 appears sustainable if current trends in new markets and applications reinforce and accelerate improvements in PV costs and performance. Through established partnerships and programs, R&D continues to focus on improving efficiency of solar energy systems, increasing manufacturing capability, reducing solar energy systems costs, enhancing reliability and flexibility of PV products, and producing innovations in thin-films and other emerging PV technologies. Continued research and market development in the US and other nations will advance quality and performance standards, and reduce the overall price of PV systems, laying the foundation for large-scale market expansion worldwide.     

中国光伏产业摆脱当前困境的对策探讨

自2011年以来,欧美光伏产品主要消费同对我国太阳能产品的进口需求大幅减少,美国的“双反”贸易诉讼更是导致中国光伏产品价格快速下跌,中国光伏企业需要寻找新的市场空间.在欧洲,德国希望通过下调太阳能补贴来控制装机速度,以减轻沉重的财政压力;西班牙和意大利在2012年光伏市场也面临衰退;但英国和法国却因为举办奥运会和欧盟对可再生能源所占份额的要求,有可能成为极具潜力的光伏产品市场;另外,乌克兰和捷克也是越来越具潜力的光伏发电市场.美国的太阳能市场在世界上越来越重要,但要占领这一市场有一定难度.亚洲是目前光伏产业发展的热点地区,但其中有些国家/地区已经或有可能成为中国大陆光伏企业的强劲对手.中国光伏企业要摆脱当前的困境,首先应立足于国内,政府要给予一定的政策支持,真正打开国内市场;成熟的欧美市场不能放弃,可采取在欧美设立分公司或建厂的战略来减少贸易摩擦;要有计划地去开发和占领东欧、亚洲和非洲等新兴市场;而最重要的,是要下大力气研发并掌握核心技术,打破国外企业对光伏产业的技术垄断,摆脱“两头在外”的局面.     

Development and Applications of Clean Coal Fluidized Bed Technology

Power generation in Europe and elsewhere relies heavily on coal and coal-based fuels as the source of energy. The reliance will increase in the future due to the decreasing stability of price and security of oil supply. In other words, the studies on fluidized bed combustion systems, which is one of the clean coal technologies, will maintain its importance. The main objective of the present study is to introduce the development and the applications of the fluidized bed technology (FBT) and to review the fluidized bed combustion studies conducted in Turkey. The industrial applications of the fluidized bed technology in the country date back to the 1980s. Since then, the number of the fluidized bed boilers has increased. The majority of the installations are in the textile sector. In Turkey, there is also a circulating fluidized bed thermal power plant with a capacity of 2 × 160 MW under construction at Can in Canakkale. It is expected that the FBT has had, or will have, a significant and increasing role in dictating the energy strategies for Turkey.     

Report on the Photovoltaic R&D Program in Hawaii

Photovoltaic systems provide one of the best options to generate energy in Hawaii, a state that is more than 90 percent dependent on imported oil for its energy supply. Hawaii's excellent year-round insolation rates will contribute to the success of solar energy projects. The Hawaii Natural Energy Institute's program to accelerate utilization of PV power in Hawaii has thus far consisted of a continuation of a 50-year data base of solar insolation; an experimental program with grid-connected residential PV systems; and public information dissemination on PV technology and performance. HNEI is now developing a program that includes: (1) compiling a solar data base that includes a full solar resource assessment, with spectral analysis and measurement of direct insolation, (2) tests of various PV devices relative to insolation; (3) test and evaluation of contemporary PV powered systems (e.g. water pumping, refrigeration, communication and stand-alone residential applications) under various tropical island conditions; and (4) a technology transfer effort aimed at Hawaii and other Pacific Basin islands, including cost-benefit and market analyses.     

Smart grid cyber security for Europe

In Europe, environmental and economic considerations are driving a revolution in power transmission and distribution. Specifically of interest to this paper, utility companies are increasingly using information and communication technology (ICT) to increase the efficiency and reliability of the grid, as well as to incorporate smaller-scale sources of intermittent wind and solar power into our electricity supply. This should have a positive effect on Europe's energy policy objectives. However, developments in the field of international security have made clear that increased reliance on ICT within the electricity sector will create new vulnerabilities that may undermine these gains.