Photovoltaic (PV) electricity: Comparative analyses of CO2 abatement at different fuel mix scales in the US

Photovoltaic electricity has the potential to mitigate CO₂ emissions from the grid. A methodology to more accurately evaluate CO₂ abatement by PV electricity is developed. We develop a capacity factor based dispatching model to evaluate marginal abatement in the load zones of ERCOT and CAISO, and compare it to the abatement using national, regional and state average resource profiles. The average cases over-estimated and under-estimated CO₂ abatement in ERCOT and CAISO, respectively. Marginal abatement was lower by 17% than the average cases in ERCOT, due to the predominant displacement of the low carbon natural gas plants at the margin. In CASIO, marginal abatement was higher (1.3–2.4 times) than that of the average cases due to the displacement of highly inefficient gas plants at the margin. We demonstrate that actual CO₂ abatement of PV electricity is dependent on both peak load resources and capacity of installations. Subsequently, we develop a CO₂ indicator that can be used as a guideline for selecting PV installation sites to derive maximum abatement. Installing photovoltaics in regional areas of MRO, SPP and RFC was determined to be most beneficial. The results of this study can guide energy planning and CO₂ mitigation policy-making using photovoltaics in the future.     

An energy-based evaluation of the matching possibilities of very large photovoltaic plants to the electricity grid: Israel as a case study

We present the results of a number of PV-grid matching simulations performed using hourly generation data from the Israel Electric Corporation (IEC) for the year 2006, together with corresponding meteorological data from Sede Boqer in the Negev Desert. The principal results of this investigation are: (1) the effective flexibility factor (ff) of the IEC grid was close to ff=0.65, but with a different plant operating strategy, ff could have been considerably higher; (2) for ff=0.65, the largest no-dump PV system could have provided only 2.7% of the annual demand, but for higher flexibilities – up to ff=1 – the percentage penetration could be as high as 17.4%; (3) considerable improvement in penetration can result by relaxing the “no-dump” criterion initially imposed on the PV system; (4) using the IEC's existing plant types, additional penetration can be expected by re-scheduling part of the base-load generating capacity to anticipate expected solar input; (5) for a radically decreased grid flexibility – that might result from IEC decisions about future generator purchases – the required employment of massive amounts of storage would render the potential contribution of PV to be insignificant.     

Potential of solar electricity generation in the European Union member states and candidate countries

During the years 2001–2005, a European solar radiation database was developed using a solar radiation model and climatic data integrated within the Photovoltaic Geographic Information System (PVGIS). The database, with a resolution of 1 km × 1 km, consists of monthly and yearly averages of global irradiation and related climatic parameters, representing the period 1981–1990. The database has been used to analyse regional and national differences of solar energy resource and to assess the photovoltaic (PV) potential in the 25 European Union member states and 5 candidate countries. The calculation of electricity generation potential by contemporary PV technology is a basic step in analysing scenarios for the future energy supply and for a rational implementation of legal and financial frameworks to support the developing industrial production of PV. Three aspects are explored within this paper: (1) the expected average annual electricity generation of a ‘standard’ 1 kW_p grid-connected PV system; (2) the theoretical potential of PV electricity generation; (3) determination of required installed capacity for each country to supply 1% of the national electricity consumption from PV. The analysis shows that PV can already provide a significant contribution to a mixed renewable energy portfolio in the present and future European Union.     

Wave electricity production in Italian offshore: A preliminary investigation

In this paper the feasibility of wave energy exploitation off the Italian coasts is investigated. At this aim, the energy production and the performance characteristics of three of the most promising and documented wave energy converters (AquaBuOY, Pelamis and Wave Dragon) are estimated for two of the most energetic Italian locations. The sites are Alghero, on the western coast of Sardinia and Mazara del Vallo, on the Sicily Strait and they have respectively an average annual wave power of 10.3 kW/m and 4 kW/m, and an available annual wave energy of 90 MWh/m and 35 MWh/m.The energy production of the hypothetical wave farms is calculated based on the performance matrices of the wave energy converters (WECs) and on 21 years of wave buoy records, covering the period from 1990 to 2011. The estimated capacity factors are low (between 4% and 9%) compared to the ones obtained for the same wave energy converters in other locations and are affected by a strong seasonal variability. This indicates that the considered WECs are oversized with respect to the local wave climate and that a more efficient energy conversion would be obtained if they were downscaled according to the typical wave height and period of the study sites. As a consequence of the optimization of the device scale, at Alghero the deployment of 1:2.5 AquaBuOY, Pelamis or Wave Dragon devices would result in capacity factors around 20% and in a quite constant energy production throughout the year. In fact, the size reduction of the wave energy converters allows to capture the energy of the small waves which would otherwise be lost with the original WECs.The results of the present work suggest that deploying classic wave energy converters in Italian seas would not be cost effective but if the devices could accommodate a proper downscaling, their performance in energy conversion would become economically attractive also for some Italian locations.     

An urban techno-economic hydrogen penetration scenario analysis for Burdur,Turkey

In this paper, the current energy mix and the power generation infrastructure of Turkey have been analyzed and two different hydrogen based alternative scenarios applied on Burdur TIMES energy model to foresee the economic and environmental results in the 2016–2031 time period.An improved RES was created to illustrate the current energy network of Burdur city and to determine the relationships between energy carriers and the respective technologies, and then this structure is specified by the relevant data, including fuel cell-powered land vehicle technologies integrated into the land transportation demand side.This paper analyses the feasibility of hydrogen as an alternative energy carrier in the fuel mix for electricity generation in Burdur City to achieve sustainable economic growth, to improve the energy security by minimizing respective environmental emissions and indicate the possible implications of the introduction of the hydrogen supply chain and respective fuel cell end-use technologies in a city level energy modelling perspective. Burdur is selected as the target city to implement the designated level of land transport passenger demand by hydrogen technologies; and after implementation of hydrogen cars in 2020; it has been evaluated that only 0.09 PJ of hydrogen car activity prevents a total of 43.44 kT CO₂ emission in Burdur, addressing the 8% of the total emission in the base scenario between the analysis time horizon. Finally, hydrogen has been evaluated as a clean, dependable option to diversify the energy mix on the current energy supply system of Burdur.     

Energy savings by co-production: A methanol/electricity case study

The overall exergy losses of co-production systems were decomposed into five sub-systems: chemical reaction processes, heat exchange processes, external exergy losses, turbine/mechanical exergy losses and others. By defining new parameters called energy-saving factors, we quantitatively describe the contribution of these processes to the overall energy savings relative to separate production systems. A methanol/electricity co-production system is taken as case study, results show that heat exchange processes are the main contribution to the energy savings.     

Solar technologies for electricity production: An updated review

This review details the most recent advancement in solar electricity production devices, in order to offer a reference for the decision-makers in the field of solar plant installation worldwide. These technologies can be classified into three main categories, namely Photovoltaics, Thermal, and Hybrid (thermal/photovoltaic). Hence, this paper begins by laying out the methodology that is used for conducting this research. Next, solar electricity production technologies are investigated and their sub-classifications are detailed to determine their resource requirements and characteristics. Subsequently, a thorough discussion is carried out. Followed by an assessment of the environmental and financial performances of each technology. Moreover, a statistical study is undertaken to highlight the efficiency and performances of each solar technology, as well as to determine their rankings in terms of electricity production worldwide. Finally, research trends related to the development of solar electricity plants are provided.     

城市生活垃圾焚烧发电CDM项目案例分析

本文分析评价了我国城市生活垃圾的产生量、资源量、国内外垃圾焚烧技术应用状况、制约我国城市生活垃圾焚烧技术应用的主要因素以及垃圾焚烧发电技术应用潜力。本研究以城市生活垃圾焚烧发电技术为案例,基于三个基准线,应用增量成本分析方法,计算了垃圾焚烧发电作为CDM(清洁发展机制)项目的单位碳减排成本并对其进行了敏感性分析,提出城市生活垃圾焚烧发电技术应作为我国与发达国家进行CDM项目合作的优先技术领域。     

Returns on investment in electricity producing photovoltaic systems under de-escalating feed-in tariffs: The case of Greece

Under the threat of ballooning energy bills, the Greek legal framework supporting the electricity producing photovoltaic systems (PVS) changed in January 2009 from a fixed to a de-escalating feed-in tariff schedule. In this paper we investigate the internal rate of return (IRR) on investing in PVS under the new regulatory environment. We find that the new scheme favours strongly the early entry in the market. Unless there is a significant decrease in the equipment cost over the next decade, entering the market from 2015 onwards will be prohibitive. The bias of the current policy design towards early entry in a rapidly developing set of technologies entails the risk of a lock-up with sub-optimal technological option. This outlines the importance for policy design of linking the rate of feed-in-tariff de-escalation to more realistic expectations regarding the technology learning curve.     

Internalizing externalities into capacity expansion planning: The case of electricity in Vietnam

This paper examines the impacts of including external costs such as environmental and health damages from power production on power generation expansion planning in Vietnam. Using the MARKAL model and covering a 20-year period to 2025, the study shows that there are substantial changes in the generation structure in favor of renewable energy technologies and other low emitting technologies. These changes lead to a reduction in fossil fuel requirements, and consequently, a reduction of CO₂, NO_x, SO₂, and PM emissions which could be expected to also reduce the associated environmental and human health impacts. The avoided external costs would be equivalent to 4.4 US cent/kWh. However, these gains are not free as the additional electricity production cost would be around 2.6 US cent/kWh higher if the switch to more expensive, but lower emitting technologies were made. The net benefit of internalizing these externalities is thus around 1.8 US cent/kWh.     

Impact of fuel-dependent electricity retail charges on the value of net-metered PV applications in vertically integrated systems

Retail electricity charges inevitably influence the financial rationale of using net-metered photovoltaic (PV) applications since their structure as well as their level may vary significantly over the life-cycle of a customer-sited PV generation system. This subsequently introduces a further uncertainty for a ratepayer considering a net-metered PV investment. To thoroughly comprehend this uncertainty, the paper employs a top-down approach – in vertically integrated environments – to model the volatility of partially hedged electricity charges and its subsequent impact on the value of bill savings from net-metered PV systems. Besides the utility's pricing strategy and rate structures, particular emphasis is given in modeling the fossil fuel mix component that introduces a significant source of uncertainty on electricity charges and thus on the value of bill savings of net-metered, customer-sited, PV applications.     

Photovoltaic technology development: A perspective from patent growth analysis

To catch up with the need for utilizing sunlight as an alternative energy source, photovoltaic technology has developed considerably fast in the last thirty-plus years. This article examines this technology's development from the perspective of patent growth analysis. Patent data are analyzed to find the photovoltaic technology growth trajectory. Mainly affected by environmental factors such as the price of crude oil, we observe two long-term waves of development trajectories. The current wave is found to be in the later growth stage of its life-cycle. After examining the correlation between technology development and crude oil price, a significant correlation is found between crude oil price's growth rate and photovoltaic patents' growth rate. As far as the market is concerned, it lags 10 years behind photovoltaic technology development.With the assistance of keyword co-occurrence analysis, one can classify photovoltaic patents into five groups, with each carrying a characteristic of competing photovoltaic technologies: Emerging PV, CdTe, CIS/CIGS, Group III–V, and Silicon technologies. This research observes the patent growth trajectories for each technology. Among these competing technologies, Emerging PV, Group III–V, and Silicon are still growing strong, while CdTe and CIS/CIGS are in the mature stage. This result hints at a paradigm shift for photovoltaic technology development. Sustainability is added to the technical regime in addition to efficiency, cost, and reliability.A policy other than the existing mechanism such as a feed-in tariff is suggested to stabilize photovoltaic technology development through the means of removing oil price fluctuations. Finally, several strategic issues are discussed from the technology development community's point of view.     

Techno-economic analysis of photovoltaic-hydrogen refueling station case study: A transport company Tunis-Tunisia

This paper sheds the light on the future of green hydrogen in Tunisia. So, a detailed economic assessment and evaluation of the Levelized Hydrogen Cost (LHC) and the Net Profit (NP) of a Photovoltaic (PV) Hydrogen Refueling Station (HRS) are presented and discussed. Tunisia is characterized by its high PV potential which makes the production of electricity from solar energy an effective alternative source. However, due to the regulations and issues related to the connection of medium PV scale to the power grid, the energy produced from renewable sources (RS) is still less than 3% of the total produced electricity. On the other hand, the price of hydrocarbon fuels is still increasing. The gap between production and total demand in hydrocarbons has created a deficit in the primary energy balance. Therefore, the production of hydrogen from solar energy for refueling Fuel Cell Vehicles (FCV)s consists of a promising solution to boost the development of the country, reduce hydrocarbon fuels consumption, and protect the environment. The sizing of a small PV-HRS to produce 150 kg of hydrogen per day shows the necessity to install PV systems with a total Direct Current (DC) capacity of 1.89 MWp. The Initial Cost (IC) analysis shows that while the PV system cost represents 48.5% of the total IC, the IC of electrolysers represents 41%. The storage system cost is approximately equal to 3.2% of the total IC. The LHC is equal to 3.32€/kg with a total IC of 2.34 million €.     

Photovoltaic building and infrastructure integration: The European experience of improvement in technology and economics

In this article the following items are discussed: (a) Why PV in buildings; (b) Why the cell costs do not tell the whole truth about PV; (c) What are “cost saving” PV building integration products; (d) What are rate-based incentives and “green pricing”; and (e) Lessons learnt and conclusions.     

A system dynamics approach to scenario analysis for urban passenger transport energy consumption and CO2 emissions: A case study of Beijing

With the accelerating process of urbanization, developing countries are facing growing pressure to pursue energy savings and emission reductions, especially in urban passenger transport. In this paper, we built a Beijing urban passenger transport carbon model, including an economy subsystem, population subsystem, transport subsystem, and energy consumption and CO₂ emissions subsystem using System Dynamics. Furthermore, we constructed a variety of policy scenarios based on management experience in Beijing. The analysis showed that priority to the development of public transport (PDPT) could significantly increase the proportion of public transport locally and would be helpful in pursuing energy savings and emission reductions as well. Travel demand management (TDM) had a distinctive effect on energy savings and emission reductions in the short term, while technical progress (TP) was more conducive to realizing emission reduction targets. Administrative rules and regulations management (ARM) had the best overall effect of the individual policies on both energy savings and emission reductions. However, the effect of comprehensive policy (CP) was better than any of the individual policies pursued separately. Furthermore, the optimal implementation sequence of each individual policy in CP was TP→PDPT→TDM→ARM.     

Forecasting weekly electricity consumption : A case study

This paper describes the application of time-series modelling techniques to electricity consumption data for a particular power board. Modelling is performed on total consumption, the data being available on a weekly basis with exact measurements for approximately the past 11 years. Both unforced and forced models are considered. An initial data analysis is performed to ascertain the influence of temperature and rainfall inputs on the model, and later on, a spectral analysis is used to investigate the frequency components present in the time-series data. A significant component of the determination of time-series models is the selection of an appropriate model order. Both low and high order models are evaluated, and their properties compared. For the unforced case, both AR (autoregressive) and ARMA (autoregressive moving average) models are considered. For the forced case, these model structures are extended to include ARX and ARMAX models which have one or more exogenous inputs. Such models are further extended by considering the possibility of predicting the inputs to the models, when a forecasting approach is required. Simulation results are provided for all cases together with a measure of the prediction accuracy. Comparisons are made for the various model structures, as well as models based on short and long data records and models which are driven with an external noise sequence or merely released from appropriate initial conditions.     

Marginal cost and congestion in the Italian electricity market: An indirect estimation approach

In this paper we construct an indirect measure of the supply marginal cost function for the main generators from the observed bid data in the Italian electricity market in the period 2004–2007. We compute the residual demand function for each generator, taking explicitly into account the issue of transmission line congestion. This procedure allows recovering correct zonal Lerner index and the implied measure of the marginal cost function. We find evidence of a stable U-shaped marginal cost function for three main Italian generators, but a flat function for ENEL, the former national monopolist. The policy relevance of our approach lies in the possibility to offer some empirical knowledge of the marginal cost function of each generator to the regulator to design appropriate policy measures geared to the promotion of competitive market conditions. We propose a new market surveillance mechanism, which is based on the principle of sanctioning excessive deviations from the estimated measure of the marginal cost function presented in this work.     

Photovoltaic projects for decentralized power supply in India: A financial evaluation

The present study concentrates on photovoltaic (PV) projects for providing decentralized power supply in remote locations in India. Results of a techno-economic evaluation are presented. Some PV projects in the capacity range 1–110 kW_p, that have either been implemented or are under implementation, have been considered. An analysis of the capital cost of the PV projects and sub-systems has been undertaken. Levelized unit cost of electricity (LUCE) has been estimated for eighteen select locations situated in different geographical regions of the country. The LUCE is found to vary in the range of Rs. 28.31–59.16/kW h (US$ 0.65–1.35/k Wh) for PV projects in the capacity range 1–25 kW_p. In view of high unit cost of electricity from PV projects, need for financial incentives has been examined from the perspective of users. A sensitivity analysis has also been undertaken.     

Geothermal power production in future electricity markets—A scenario analysis for Germany

Development and diffusion of new renewable energy technologies play a central role in mitigating climate change. In this context, small-scale deep geothermal power has seen growing interest in recent years as an environmentally friendly, non-intermittent energy source with large technical potential. Following the first successful demonstration projects, the German geothermal industry is currently experiencing an internationally unparalleled growth. In this study we explore the factors driving this development, and the role geothermal power production could play in the future of the German electricity market. For this, we apply the scenario technique, based on literature analysis and interviews with companies operating actively in the field. Our findings highlight the importance of political support and framework conditions in the electricity market, with the best prospects in a decentralised energy system based on renewable energy sources, where high investment costs and the risk of discovery failure are balanced by the benefits of low-carbon base load power.