Parameter study for dimensioning of a PV optimized hydrogen supply plant

Green hydrogen produced from intermittent renewable energy sources is a key component on the way to a carbon neutral planet. In order to achieve the most sustainable, efficient and cost-effective solutions, it is necessary to match the dimensioning of the renewable energy source, the capacity of the hydrogen production and the size of the hydrogen storage to the hydrogen demand of the application.For optimized dimensioning of a PV powered hydrogen production system, fulfilling a specific hydrogen demand, a detailed plant simulation model has been developed. In this study the model was used to conduct a parameter study to optimize a plant that should serve 5 hydrogen fuel cell buses with a daily hydrogen demand of 90 kg overall with photovoltaics (PV) as renewable energy source. Furthermore, the influence of the parameters PV system size, electrolyser capacity and hydrogen storage size on the hydrogen production costs and other key indicators is investigated. The plant primarily uses the PV produced energy but can also use grid energy for production.The results show that the most cost-efficient design primarily depends on the grid electricity price that is available to supplement the PV system if necessary. Higher grid electricity prices make it economically sensible to invest into higher hydrogen production and storage capacity. For a grid electricity price of 200 €/MWh the most cost-efficient design was found to be a plant with a 2000 kWp PV system, an electrolyser with 360 kW capacity and a hydrogen storage of 575 kg.     

State-scale evaluation of renewable electricity policy: The role of renewable electricity credits and carbon taxes

We have developed a state-scale version of the MARKAL energy optimization model, commonly used to model energy policy at the US national scale and internationally. We apply the model to address state-scale impacts of a renewable electricity standard (RES) and a carbon tax in one southeastern state, Georgia. Biomass is the lowest cost option for large-scale renewable generation in Georgia; we find that electricity can be generated from biomass co-firing at existing coal plants for a marginal cost above baseline of 0.2–2.2 cents/kWh and from dedicated biomass facilities for 3.0–5.5 cents/kWh above baseline. We evaluate the cost and amount of renewable electricity that would be produced in-state and the amount of out-of-state renewable electricity credits (RECs) that would be purchased as a function of the REC price. We find that in Georgia, a constant carbon tax to 2030 primarily promotes a shift from coal to natural gas and does not result in substantial renewable electricity generation. We also find that the option to offset a RES with renewable electricity credits would push renewable investment out-of-state. The tradeoff for keeping renewable investment in-state by not offering RECs is an approximately 1% additional increase in the levelized cost of electricity.     

Economic analysis of different supporting policies for the production of electrical energy by solar photovoltaics in western European Union countries

Within various renewable energy technologies, photovoltaics (PV) today attracts considerable attention due to its potential to contribute a major share of renewable energy in the future. However, PV market development is, undoubtedly, dependent on the political support of any given country.     

Market power in renewable portfolio standards

Renewable portfolio standard (RPS), which requires a certain percentage of electricity production from renewables, has received considerable attention. One emerging issue is the possibility of strategic behavior in the renewable energy certificate/credit (REC) market, and its spillover effects on the electricity market. This paper develops dominant firm-competitive fringe models that account for market power. We show that market power could have significant impacts on the REC and power prices. In particular, when a nonrenewable generator is a dominant firm and a renewable generator is a competitive fringe, the nonrenewable firm has a strong incentive to lower the REC price, even to zero for avoiding REC costs. The zero REC price would negate price impacts in the power market, thereby mitigating market power of the dominant firm. However, this could lead to an underinvestment in renewables in the long run as subsidies received by renewables in form of RECs vanish. Therefore, regulatory agencies need to carefully oversee the market performance to ensure a healthy development of renewable industries under the RPS policies.     

China’s renewable energy policy: Commitments and challenges

The passing of the Renewable Energy Law (REL) in 2005 demonstrated China’s commitment to renewable energy development. In the 3 years after the REL, China’s renewable electricity capacity grew rapidly. From 2006 to 2008, China’s wind capacity installation more than doubled every year for 3 years in a row. However, three facts prevent us from being optimistic about China’s renewable electricity future. First, considered as a share of total capacity, renewable electricity capacity is decreasing instead of increasing. This is due simply to the rapid growth of fossil fuel capacity. Second, a significant amount of renewable generation capacity is wasted because it is not connected to the electricity grid. Finally, renewable electricity plants are running at a low level of efficiency. Based on an in-depth analysis of China’s existing renewable energy policy, we suggest that these challenges should be dealt with by introducing a market-based mandatory renewable portfolio requirement coupled with strong regulatory monitoring of grid enterprises.     

Risk adjusted financial costs of photovoltaics

Recent research shows significant differences in the levelised photovoltaics (PV) electricity cost calculations. The present paper points out that no unique or absolute cost figure can be justified, the correct solution is to use a range of cost figures that is determined in a dynamic power portfolio interaction within the financial scheme, support mechanism and industry cost reduction. The paper draws attention to the increasing role of financial investors in the PV segment of the renewable energy market and the importance they attribute to the risks of all options in the power generation portfolio. Based on these trends, a former version of a financing model is adapted to project the energy mix changes in the EU electricity market due to investors behaviour with different risk tolerance/aversion. The dynamic process of translating these risks into the return expectation in the financial appraisal and investment decision making is also introduced. By doing so, the paper sets up a potential electricity market trend with the associated risk perception and classification. The necessary risk mitigation tasks for all stakeholders in the PV market are summarised which aims to avoid the burden of excessive risk premiums in this market segment.     

Photovoltaic electricity production of a grid-connected urban house in Serbia

A technically attractive solution for sustainable present and future is to integrate photovoltaic (PV) panels into building fabric of urban houses as an alternative to grid electricity, however, in Serbia this technology is rarely applied. To contribute to sustainability and create success conditions for renewable energy sources (RES) applications due its wish to join EU, Serbian government currently integrated RES into its new energy policy framework. In the near future in the separate law, the government will identify financial conditions to apply this policy and start RES use. To adequately inform this law, we calculated the electricity revenue during entire life of a two-floor house in Belgrade, Serbia and investment in PV panels (currently available on Serbian market) integrated in its entire envelope. It was discussed what are the current degree of economic viability of this solution and suggested level of state subventions needed to support the solar electricity production either by feed-in tariffs or other financial instruments.     

Biomass assessment and small scale biomass fired electricity generation in the Green Triangle, Australia

Coal fired electricity is a major factor in Australia’s greenhouse gas emissions (GHG) emissions. The country has adopted a mandatory renewable energy target (MRET) to ensure that 20% of electricity comes from renewable sources by 2020. In order to support the MRET, a market scheme of tradable Renewable Energy Certificates (RECs) has been implemented since 2001. Generators using biomass from eligible sources are able to contribute to GHG emission reduction through the substitution of coal for electricity production and are eligible to create and trade RECs. This paper quantifies the potential biomass resources available for energy generation from forestry and agriculture in the Green Triangle, one of the most promising Australian Regions for biomass production. We analyse the cost of electricity generation using direct firing of biomass, and estimate the required REC prices to make it competitive with coal fired electricity generation. Major findings suggest that more than 2.6 million tonnes of biomass are produced every year within 200 km of the regional hub of Mount Gambier and biomass fired electricity is viable using feedstock with a plant gate cost of 46 Australian Dollars (AUD) per tonne under the current REC price of 34 AUD per MWh. These findings are then discussed in the context of regional energy security and existing targets and incentives for renewable energies.     

Investment appraisal of a small, grid-connected photovoltaic plant under the Serbian feed-in tariff framework

Serbian government has recently introduced the system of feed-in tariffs for electricity generated from renewable sources. The proposed feed-in tariff for photovoltaic electricity is set to 0.23 €/kWh paid for 12 years, with the PV electricity produced after the first 12 years being sold at the grid electricity market price for the rest of the plant lifetime. Although such FIT could have been justified by the small, average retail grid electricity price of just 0.054 €/kWh for Serbian households, the investment appraisal of a real case of 2.82 kWp PV power plant in two Serbian cities of Zlatibor and Negotin, clearly illustrates that the proposed FIT framework is not sufficient to attract investments into PV in Serbia. In the second part of the paper, we have analyzed alternative, more reasonable feed-in tarrif frameworks, with the goal of selecting those able to sustain the PV adoption and diffusion in Serbia.     

Evaluating the potential of small-scale renewable energy options to meet rural livelihoods needs: A GIS- and lifecycle cost-based assessment of Western China's options

The economics and livelihoods impacts of stand-alone, small-scale (less than 2 kW) renewable energy technologies for rural electrification are assessed using a representative sample of 531 rural households in three provinces of Western China. Over 20 small wind, photovoltaic (PV) and wind–PV hybrid configurations were evaluated for their potential to meet local electricity needs. The assessment integrates lifecycle costing and geographic information system (GIS) methods in order to provide a comprehensive resource, economic, technological and livelihoods assessment. The results of the analysis indicate that off-grid renewable energy technologies can provide cost-effective and reliable alternatives to conventional generator sets in addressing rural livelihoods energy requirements. Findings also demonstrate the existence of a sizeable market potential for stand-alone renewable energy systems in Western China. In support of market development for these technologies, policy recommendations are provided.     

Accounting for variation in wind deployment between Canadian provinces

Wind energy deployment varies widely across regions and this variation cannot be explained by differences in natural wind resources alone. Evidence suggests that institutional factors beyond physical wind resources can influence the deployment of wind energy systems. Building on the work of Toke et al. (2008), this study takes a historical institutionalist approach to examine the main factors influencing wind energy deployment across four Canadian provinces Canada: Alberta, Manitoba, Ontario and Nova Scotia. Our case studies suggest that wind energy deployment depends upon a combination of indirect causal factors—landscape values, political and social movements, government electricity policy, provincial electricity market structure and incumbent generation technologies and direct causal factors—grid architecture, ownership patterns, renewable incentive programs, planning and approvals processes and stakeholder support and opposition.     

Making the case for grid-connected photovoltaics in Brazil

In the developed world, grid-connected photovoltaics (PVs) are the fastest-growing segment of the energy market. From 1999 to 2009, this industry had a 42% compound annual growth-rate. From 2009 to 2013, it is expected to grow to 45%, and in 2013 the achievement of grid parity – when the cost of solar electricity becomes competitive with conventional retail (including taxes and charges) grid-supplied electricity – is expected in many places worldwide. Grid-connected PV is usually perceived as an energy technology for developed countries, whereas isolated, stand-alone PV is considered as more suited for applications in developing nations, where so many individuals still lack access to electricity. This rationale is based on the still high costs of PV when compared with conventional electricity. We make the case for grid-connected PV generation in Brazil, showing that with the declining costs of PV and the rising prices of conventional electricity, urban populations in Brazil will also enjoy grid parity in the present decade. We argue that governments in developing nations should act promptly and establish the mandates and necessary conditions for their energy industry to accumulate experience in grid-connected PV, and make the most of this benign technology in the near future.     

Boosting new renewable technologies towards grid parity – Economic and policy aspects

The intensity of market penetration and hence the relevance of clean energy technologies in mitigating climate change will greatly depend on their cost-effectiveness. This paper discusses the economic and policy aspects of speeding up the market of these technologies to reach cost parity. A combination of historical energy market dynamics, technology diffusion and endogenous learning models were employed in the analyses. Starting from giving a preferential position to emerging renewable energy technologies in the energy and climate policy, which also means securing adequate financial resources for their deployment, could lead in the base scenario to a full-cost breakthrough of wind power around 2027 and of photovoltaics in 2032. The combined global market share of renewable electricity in 2050 could reach 62% of all electricity (now 19%) of which wind and solar power alone could account for almost two-thirds corresponding to a carbon saving in the range of 8–16 GtCO₂. However, if the new technologies were downgraded in the energy and climate policy context, the combined impact of solar and wind could remain at no less than 11% which would marginalize these technologies in the fight against climate change. The estimates for financial support to achieve cost parity were very sensitive to the assumptions of the input parameters: in the base case the extra costs or learning investments for solar power were €1432 billion and for wind power €327 billion, but with more conservative input data these values could grow manifold. On the other hand, considering the potentially cheaper electricity from new technologies above the cost parity point and putting a price on carbon could result in a positive yield from public support instead of it being regarded merely as unnecessary spending. The findings stress the necessity of long-term policies and strong commercialization strategies to bring the new energy technologies to breakeven point, but also highlight the complexity of assessing the true costs of making new energy technologies fully competitive.     

Joint electricity and carbon market for Northeast Asia energy interconnection

Decarbonization of the electricity sector is crucial to mitigate the impacts of climate change and global warming over the coming decades. The key challenges for achieving this goal are carbon emission trading and electricity sector regulation, which are also the major components of the carbon and electricity markets, respectively. In this paper, a joint electricity and carbon market model is proposed to investigate the relationships between electricity price, carbon price, and electricity generation capacity, thereby identifying pathways toward a renewable energy transition under the transactional energy interconnection framework. The proposed model is a dynamically iterative optimization model consisting of upper- level and lower-level models. The upper-level model optimizes power generation and obtains the electricity price, which drives the lower-level model to update the carbon price and electricity generation capacity. The proposed model is verified using the Northeast Asia power grid. The results show that increasing carbon price will result in increased electricity price, along with further increases in renewable energy generation capacity in the following period. This increase in renewable energy generation will reduce reliance on carbon-emitting energy sources, and hence the carbon price will decline. Moreover, the interconnection among zones in the Northeast Asia power grid will enable reasonable allocation of zonal power generation. Carbon capture and storage (CCS) will be an effective technology to reduce the carbon emissions and further realize the emission reduction targets in 2030-2050. It eases the stress of realizing the energy transition because of the less urgency to install additional renewable energy capacity.     

State renewable energy electricity policies: An empirical evaluation of effectiveness

Over the past decade, state governments have emerged as US energy policy leaders. Across the country, states are adopting policy instruments aimed at carbon mitigation and renewable energy deployment. One of the most prevalent and innovative policy instruments is a renewable portfolio standard (RPS), which seeks to increase the share of renewable energy electrification in the electricity market. This analysis evaluates the effectiveness of state energy programs with an empirical investigation of the linkage between state RPS policy implementation and the percentage of renewable energy electricity generation across states. We use a variant of a standard fixed effects model, referred to as a fixed effects vector decomposition, with state-level data from 1998 to 2006. Results indicate that RPS implementation is not a significant predictor of the percentage of renewable energy generation out of the total generation mix, yet for each additional year that a state has an RPS policy, they are found to increase the total amount of renewable energy generation. These findings reveal a potentially significant shortcoming of RPS policies. Political institutions, natural resource endowments, deregulation, gross state product per capita, electricity use per person, electricity price, and the presence of regional RPS policies are also found to be significantly related to renewable energy deployment.     

可再生能源绿证价格季节性测算方法研究

  目的  在市场化交易模式消纳可再生能源发电的发展趋势下,“市场电价+绿证收入”将成为未来可再生能源发电企业的主要经营模式。以可再生能源发电参与现货电能量市场为研究大背景,对可再生能源绿色电力证书的价格进行研究。  方法  基于现货电能量市场的优化出清模型,应用可再生能源全生命周期成本测算理论,以满足可再生能源发电企业的内部收益为目的,建立了绿证-电能量市场耦合的优化模型,并结合可再生能源季节性出力特性,提出了可再生能源绿证价格季节性曲线及其波动区间的仿真和测算方法。  结果  不同类型的可再生能源绿证价格不同,不同类型的可再生能源绿证价格的气候相关性亦不相同。  结论  绿证价格的科学合理测算不仅可以帮助可再生能源发电企业进行收益评估和制定更为准确的投资决策,还为电力市场主体与交易中心提供相关决策支持。     

The economic and institutional rationale of PV subsidies

In terms of cost and performance, infant technologies, such as solar photovoltaics (PV), are normally inferior to entrenched technologies. It is a Catch-22 situation since the diffusion on larger markets that would be needed to reduce cost is hindered by the high cost. Therefore it would make sense to subsidise PV to increase sales, which would increase experience and induce investments in larger factories, which in turn would drive down costs and the subsidies needed. The total costs of such a scheme does not have to be prohibitive if cost reductions with increased volumes are large enough. Over the last 20 years the cost of PV modules was reduced by 18–23% per doubling of cumulative production (a progress ratio of 0.77–0.82). For a progress ratio of 0.80 and an annual growth rate of 30%, the modelled annual subsidy peaks at $14 US billion, which corresponds to an additional electricity tax of no more than 0.1 US cents/kW h in OECD countries. A market support programme also creates institutional learning and increases the political power of the proponents of PV. The current federal German support programme is a product of learning and network formation in earlier market stimulation and research, development and demonstration (RDD) programmes of smaller scale. Hence, the current support programme is now likely to create not only economic virtuous circles that reduce costs, but also institutional virtuous circles that work for the survival and expansion of the programme itself. As the PV industry grows, care should be taken to maintain variety to reduce the risk of a premature lock-in of an inferior design. To maintain variety in the market place may prove costly when the market grows but variety creation at the level of RDD investments is fairly cheap. To increase the world expenditure on RDD of renewable energy technology by a factor of 10 would not cost more than $1 US/ton C or 0.02 US cent/kW h of electricity.     

Potential and use of renewable energy sources in Croatia

The current share of renewable energy sources in electricity production in Croatia is very high, around 50%. Nevertheless it is expected that the share of renewables will have to rise and efficient strategies must be examined and adopted. The Croatian government has recognised the important role renewable energy sources could play in Croatian energy and electricity supply. The most important barrier for a wider deployment of renewables in energy production is their cost which is still above those of conventional energy sources. As the energy market is currently undergoing the process of liberalisation, support mechanisms that are compatible with an open market philosophy must be adopted. The characteristics of the Croatian power system, the expected consumption, growth and possible future role of renewables in energy and electricity production is presented. The current legislative framework relevant for renewables is analysed and discussed.     

A survey of the current photovoltaic equipment industry in Brazil

The use of renewable alternative sources of energy in the world has been growing in the last few decades due to concerns about dependence on fossil sources and to environmental reasons, related to climatic change and its effects on mankind. Tax and/or financial incentives have been instituted for the population, to have access to renewable source technologies, and for the local equipment industry, to develop more quickly. In Brazil, the PV (photovoltaic) equipment to convert solar into electricity is more often used in low income rural communities, located distant from the grid network, for rural electrification, water pumping and public illumination. However, since there is no currently specific regulatory incentive mechanism for this source in the country, the Brazilian PV equipment industry has not made great advances and the market is largely dominated by multinationals. Against this background, a survey of the current PV equipment industry in Brazil is extremely relevant, especially in the event of a national program development to promote the use of this technology, stimulate the domestic industry and reduce the dependence on imported equipment.     

Renewable energy policy in Turkey with the new legal regulations

Since the energy crises in the 1970’s, public and private decision makers are considering how to achieve a sustainable transition from fossil fuel based energy to sustainable and clean energies - namely renewable energies. Combined with the improvement of energy efficiency and the rational use of energy, renewable energy can provide everything fossil fuels currently offer in terms of heating and cooling, electricity generation and transportation. Renewable energy technologies posses many long term benefits including energy security, job creation, business opportunities, sustainable development and prevention of global warming.Turkey’s population is growing at an annual rate of 1.04%. If Turkey uses only traditional energy sources, it simply will not have enough energy capacity for its population. Renewable energy sources have the potential to make a large contribution to Turkey’s sustainable and independent energy future.Turkey aims to utilize its energy potential, including from renewable sources in a cost-effective manner. Turkey targets the share of renewable resources in electricity generation to be at least 30% by 2023 has in its 2009 Electricity Market and Security of Supply Strategy. Positive achievements have been obtained in renewable energy development and manufacturing in Turkey over the past decade. The renewable energy related legislation has been intensified. To meet its 30% target, the current promotion mechanism for renewable sources of electricity relies on feed-in tariffs for different renewable energy sources. Large hydropower is already competitive to conventional fossil-based electricity, so feed-in tariffs in the new RE Law are set to facilitate expanding the deployment of other, less mature renewable energy technologies.