Pathways to a more sustainable production of energy: sustainable hydrogen—a research objective for Shell

Towards a sustainable energy supply is a clear direction for exploratory research in Shell. Examples of energy carriers, which should be delivered to the envisaged sustainable energy markets, are bio-fuels, produced from biomass residues, and hydrogen (or electricity), produced from renewable sources. In contrast to the readily available ancient sunlight stored in fossil fuels, the harvesting of incident sunlight will be intermittent, efficient electricity and hydrogen storage technologies need to be developed. Research to develop those energy chains is going on, but the actual transformation from current fossil fuel based to sustainable energy markets will take a considerable time. In the meantime the fossil fuel based energy markets have to be transformed to mitigate the impact of the use of fossil fuels. Some elements in this transformation are fuels for ultra-clean combustion (hydrocarbons and oxygenates), hydrogen from fossil fuels, fuels for processors for fuel cells, carbon sequestration.     

我国生物质能源现代化应用前景展望(一)——生物质资源和供给

生物质能除了可以在改善世界一次能源结构、降低化石能源需求量方面做出重要贡献以外,还可在减少温室气体排放、保障能源供应安全、改善贸易平衡、促进农村发展和改进城市废弃物处理方式等方面发挥作用。目前全球每年一次能源消费总量为500EJ,生物质资源的年用量约占一次能源消费总量的10%左右,主要被用于传统的民用燃料和生产第一代生物燃料。第二代生物燃料技术预计将于2020年前后在一些国家实现工业化生产。IEA预测,2050年世界一次能源需求量为670EJ,生物质资源将占一次能源需求总量的20%左右。各方学者预测的2050年全球生物质资源量最低值基本在200~400EJ之间,最高值在400~1500EJ之间。中国的生物燃料产业尚处于起步阶段,不过应该说取得了良好的开端。我国生物质资源相对较少,且分布不均,发展生物质能产品需要依靠能源作物。只有通过合理开发、有效利用,才能在不与粮食和食用油争夺土地的前提下,在一定程度上提供生物运输燃料和生物质发电供热所需的原料,生物质能-农产品和/或生物质能-林产品联合生产系统应成为主要发展方向。美国生物燃料产业的发展模式对我国具有一定的借鉴意义。生物质最有效的利用方式是生产运输燃料,从长远来看,生物燃料可以与石油燃料竞争,尤其是喷气燃料和汽油更具替代优势,但受到生物质资源供应量的制约。     

Analysis of olive grove residual biomass potential for electric and thermal energy generation in Andalusia (Spain)

As fossil fuels are not only a limited resource, but also contribute to global warming, a transition towards a more sustainable energy supply is urgently needed. Therefore, today's environmental policies are largely devoted to fostering the development and implementation of renewable energy technologies. One important aspect of this transition is the increased use of biomass to generate renewable energy. Agricultural residues are produced in huge amounts worldwide, and most of this residue is composed of biomass that can be used for energy generation. Consequently, converting this residue into energy can increase the value of waste materials and reduce the environmental impact of waste disposal. This paper analyses the situation of biomass energy resources in Andalusia, an autonomous community in the south of Spain. More specifically, biomass is the renewable source which most contributes to Andalusian energy infrastructure. The residual biomass produced in the olive sector is the result of the large quantity of olive groves and olive oil manufacturers that generate byproducts with a potentially high energy content. The generation of agricultural and industrial residues from the olive sector produced in Andalusia is an important source of different types of residual biomass that are suitable for thermal and electric energy since they reduce the negative environmental effects of emissions from fossil fuels, such as the production of carbon dioxide.     

Sustainable energy: A review of gasification technologies

Biomass has been widely recognized as a clean and renewable energy source, with increasing potential to replace conventional fossil fuels in the energy market. The abundance of biomass ranks it as the third energy resource after oil and coal. The reduction of imported forms of energy, and the conservation of the limited supply of fossil fuels, depends upon the utilization of all other available fuel energy sources. Energy conversion systems based on the use of biomass are of particular interest to scientists because of their potential to reduce global CO₂ emissions. With these considerations, gasification methods come to the forefront of biomass-to-energy conversions for a number of reasons. Primarily, gasification is more advantageous because of the conversion of biomass into a combustible gas, making it a more efficient process than other thermochemical processes. Biomass gasification has been studied widely as an efficient and sustainable technology for the generation of heat, production of hydrogen and ethanol, and power generation. Renewable energy can have a significant positive impact for developing countries. In rural areas, particularly in remote locations, transmission and distribution of energy generated from fossil fuels can be difficult and expensive, a challenge that renewable energy can attempt to correct by facilitating economic and social development in communities. This paper aims to take stock of the latest technologies for gasification.     

Woody biomass supply potential for thermal power plants in Japan

Biomass energy is one of mitigation method of CO₂ reduction. In Japan, it aimed to reduce fossil fuels supply 670,000 kL of crude oil equivalent in thermal power plants and 340,000 kL of crude oil equivalent in the utilization of heat by biomass. It was decided to use 25% or more of the forestry products such as logging residues. Japanese government aim to supply 634 PJ of woody biomass for power generation in 2010. This amount of energy accounts for 2.8% of total primary energy. More than 68% of Japan is covered by forests, and more than 40% of these forests are plantations. But the use of woody biomass is limited because it is still not seen as economically viable. In this article, we developed a large scale forestry economic model which can estimate the wood chips supply for coal thermal power plants across all around Japan. By using this model, wood chips supply potential is currently 32,000 m³/year and supply will increase drastically when wood chips price increase or carbon credit is installed and we found that biomass production of 15 PJ that is the numeric target of Japanese government is possible. Especially, the lengthening of rotation period of forestry and the decrease of wood chips transportation cost is important for wood chips use in coal thermal plant.     

Effect of policy-based bioenergy demand on southern timber markets: A case study of North Carolina

Key factors driving renewable energy demand are state and federal policies requiring the use of renewable feedstocks to produce energy (renewable portfolio standards) and liquid fuels (renewable fuel standards). However, over the next decade, the infrastructure for renewable energy supplies is unlikely to develop as fast as both policy- and market-motivated renewable energy demands. This will favor the use of existing wood as a feedstock in the first wave of bioenergy production. The ability to supply wood over the next decade is a function of the residual utilization, age class structure, and competition from traditional wood users. Using the North Carolina Renewable Portfolio Standard as a case study, combined with assumptions regarding energy efficiency, logging residual utilization, and traditional wood demands over time, we simulate the impacts of increased woody biomass demand on timber markets. We focus on the dynamics resulting from the interaction of short-run demand changes and long-term supply responses. We conclude that logging residuals alone may be unable to meet bioenergy demands from North Carolina’s Renewable Portfolio Standard. Thus, small roundwood (pulpwood) may be used to meet remaining bioenergy demands, resulting in increased timber prices and removals; displacement of traditional products; higher forest landowner incomes; and changes in the structure of the forest resource.     

生物质应用于制液体和气体燃料而不是用于发电

我国能源结构从长期看仍将以煤为主,缺油少气。从我国能源结构来讲,生物质利用的最好方式不是发电．因生物质可以生产液体和气体燃料,而风能、太阳能、水能却只能发电。我国秸杆综合利用取得明显成效．在农业和畜牧业的利用领域还可能进一步拓宽,作为燃料利用的量还可能进一步缩减。从我国还在进行的第一次能源大转换来看,我国生物质使用量已大大减少,但还有相当的数量。要减少作为能源使用的生物质传统利用量,把它用于饲料、肥料和工业原料等还有发展前景的用途。在一次能源消费以化石能源为主的时期,中国存在液体燃料和气体燃料短缺的问题,以后进入第三次能源转换时期,新能源和可再生能源替代化石能源之后,液体燃料和气体燃料短缺的问题将会更加突出。因此,生物质应用于生产液体燃料和气体燃料,而不是用于发电。而且生物质发电厂投资高、燃料成本不断上涨,使发电成本高＋生物质发电将长期缺乏竞争力。我国发展生物质液体燃料已具备一定的条件．前几年中石油、中石化和中海油已开始种植可提炼生物液体燃料的能源林。我国非粮生物质液体燃料生产基地正在积极建设之中。我国发展生物质气体燃料也具有一定优势,在沼气、气化和城镇有机废物处理方面都积累了一定的经验。总之生物质生产液体燃料和气体燃料是一种既适应我国当前、又适应未来能源需求的有效措施。     

The promise of clean energy

The world's energy system is at least a 1.5 trillion dollars market dominated by fossil fuels, where small changes can have a large influence on efforts to reach sustainability. Renewable energy sources are key to achieving this goal. Excluding traditional biomass, in 2001 renewables represented 4.4% of primary energy consumption, unevenly distributed between developed and developing countries. Environmental problems at local, regional and global levels, as well as external dependency and security of supply will persist if we rely on an energy future based on fossil fuels. Solutions encompass extending the life of fossil fuel reserves and expanding the share of renewable in the world energy system through top down and bottom up policies, described in this paper.     

Climatic impact of alternative energy sources

Detailed evaluations have suggested that the order of magnitude of energy demand 50 yr from the present will be 25–40 TW compared with about 8 TW at the present day. Three energy supply sources could be developed on a large enough scale to satisfy a demand of this magnitude: solar and nuclear energy and fossil fuels. The potential climate impact of the large-scale deployment of solar energy conversion systems has not been evaluated in detail. Solar thermal electric conversion systems could impact climate through large-scale changes in the energy balance at the earth's surface, in the surface roughness and in the surface wetness. Photovoltaic conversions could impact climate by acting as a local heat source. Ocean thermal electric conversion systems would have their main impact through changes in ocean surface temperature, but could also interfere with major ocean currents and have an impact through release of CO₂ into the atmosphere or albedo changes, for example. The cultivation of plants for biomass conversion systems could influence climate through causing large-scale changes in the surface characteristics. The biomass conversion could also impact climate through releases of gases and particulate matter into the atmosphere. Through the use of climate models and observational studies, these impacts should be studied in more detail. In the meantime, the climate constraint should be kept in mind during the development of energy policy and the policies should be kept flexible at the present time until some of the uncertainties about the climate system have been resolved.     

Identifying and addressing barriers to renewable energy development in Pakistan

To ensure a sustainable energy future for Pakistan, it is necessary that the energy sector be accorded a high priority. Pakistan remains predominantly reliant on fossil fuels as its primary source of energy. Efforts to reduce reliance on fossil fuels through increasing the share of renewable energy in the energy supply systems have met with little success so far. The barriers to development of renewable energy can be broadly classified as policy and regulatory barriers, institutional barriers, fiscal and financial barriers, market-related barriers, technological barriers and information and social barriers. In this article, an effort has been made to identify the barriers that limit the use of renewable energy technologies in general and with specific reference to Pakistan, and outline the measures to address these barriers.     

中国生物质成型燃料产业政策与执行效果分析

生物质固体成型燃料因其碳中性、氮硫含量低、烟气污染少、便于运输等优势,在供热、供气以及发电方面可以大量替代煤炭、天然气或重油,在有效供能的同时,能够显著减少污染,实现CO2零排放,符合当前社会可持续发展的理念。尽管我国出台了一系列激励政策,但是在产业发展的过程中还存在一定问题,产业发展离国家目标还有一定差距。本文对目前国内外已出台的生物质成型燃料产业政策进行了归纳和总结,并对我国的关键产业政策,如秸秆能源化补贴政策、税收减免政策、环保措施政策、贷款优惠的执行效果做了跟踪调研,对不同政策的执行力度与成效做了评价和分析,最终给出了政策改进建议。     

Increasing the sustainability of household cooking in developing countries: Policy implications

Although 40% of the global population relies on traditional biomass use, mainly firewood and charcoal, for cooking, traditional biomass has received very little attention in the current biomass debate, because of its considered primitive and unsustainable nature. In this review, we discuss how the sustainability of household cooking in developing countries can be improved.Indoor air pollution due to incomplete combustion of traditional biomass causes the death of 1.45 million people every year, mainly of women and children, who also carry the heavy burden of fuelwood collection. In addition, charcoal production and combustion is responsible for very high greenhouse gas emissions per unit of energy. On the other hand, fuelwood production and trade is of vital importance for local economies and serves as safety net for the poorest people. Moreover, fuelwood collection is not a driver of deforestation and global fuelwood shortage will not occur, despite local problems of fuelwood provision.There are two distinct policy alternatives to increase the sustainability of cooking in developing countries. The first option is to climb the energy ladder and to switch from solid fuels to fossil fuels (LPG or kerosene), biogas or electricity. As this largely avoids the severe health damages of traditional biomass use, this option is considered the most desirable by numerous countries and by international organizations. However, as most developing countries are far away from meeting the necessary requirements, related to infrastructure, economics and local culture, expecting a large-scale switch to liquid fuels or electricity is unrealistic.In that case, the second policy option, increasing the sustainability of the current traditional biomass system, must be considered. This can be realized by an integrated approach, in which national and regional fuelwood policies are adapted, improved systems for charcoal production are implied and improved stoves, in combination with chimneys, are distributed.     

Socio-economic aspects of different biofuel development pathways

There are several policy drivers for biofuels on a larger scale in the EU transport sector, including increased security of energy supply, reduced emission of greenhouse gases (GHG), and new markets for the agricultural sector. The purpose of this socio-economic cost analysis is to provide an overview of the costs of meeting EU biofuels targets, taking into account several external costs and benefits. Biofuels are generally more expensive than traditional fossil fuels, but the expected increasing value of GHG emission reductions will over time reduce the cost gap. High crude oil prices significantly improve the economic benefit of biofuels, but increased demand for biomass for energy purposes is likely to increase the price of biofuels feedstock and biofuels costs. The key question is to what extent increasing oil prices will be passed on to biofuels costs. Socio-economic least costs for biofuels production require a market with a clear pricing of GHG emissions to ensure that this factor is included in the decision-making of actors in all links of the fuel chain.     

Potential of the renewable energy development in Jammu and Kashmir,India

The future economic growth for India is likely to result in rapid and accelerated surge in energy demand, with expected shortages in terms of supply. Many of its current policies and strategies are aimed at the improvement and possible maximization of energy production from the renewable sector. It is also clear that while energy conservation and energy efficiency can make an important contribution, renewable energies will be essential to the solution and are likely to play an increasingly important role for providing enhanced energy access, reducing consumption of fossil fuels, and helping India pursue its low-carbon progressive pathway. However, most of the states in India, like the northernmost state of Jammu and Kashmir, have experienced an energy crisis over a sustained period of time and the government both at center and state level has to embark upon with these pressing issues in a more sustainable manner and accordingly initiate various renewable energy projects within these states. This paper will provide a broad-spectrum view about the energy situation within Jammu and Kashmir and will highlight the current policies along with future strategies for the optimal utilization of renewable energy resources.     

对我国风电发展战略的冷思考

我国风电发展迅速,计划2010年风电装机容量要达到3500×10^4kW,2020年达到1.5×10^8kW。据IEA预测,2030年世界能源供应仍以化石能源为主,其比重由2006年的80.8%下降到80.4%;2030年世界发电能源结构也以化石能源发电为主,其比重由2006年的74%下降到73%。中国到21世纪中叶传统化石能源仍将居绝对优势地位。因此在可再生能源和新能源的开发过程中,不要急于求成,片面追求能源和电源结构优化不可取。我国未来要依靠核电和新能源发电,但需要通过对其技术经济的进一步研究,才能确定主要靠核电还是风电、太阳能发电或生物质能发电。目前我国风电发展的主要问题是对风电的技术要求起点低,技术路线不对,从国外引进了落后的风电技术。为了我国风电的健康发展,必须加快风电合理利用的研究,包括风电储能和风电直接利用的研究。     

Heat planning for fossil-fuel-free district heating areas with extensive end-use heat savings: A case study of the Copenhagen district heating area in Denmark

The Danish government plans to make the Danish energy system to be completely free of fossil fuels by 2050 and that by 2035 the energy supply for buildings and electricity should be entirely based on renewable energy sources. To become independent from fossil fuels, it is necessary to reduce the energy consumption of the existing building stock, increase energy efficiency, and convert the present heat supply from fossil fuels to renewable energy sources. District heating is a sustainable way of providing space heating and domestic hot water to buildings in densely populated areas. This paper is a theoretical investigation of the district heating system in the Copenhagen area, in which heat conservation is related to the heat supply in buildings from an economic perspective. Supplying the existing building stock from low-temperature energy resources, e.g. geothermal heat, might lead to oversized heating plants that are too expensive to build in comparison with the potential energy savings in buildings. Long-term strategies for the existing building stock must ensure that costs are minimized and that investments in energy savings and new heating capacity are optimized and carried out at the right time.     

The emerging liquid biofuel market in Argentina: Implications for domestic demand and international trade

While the world's transport energy matrix is still strongly linked to limited and heavily polluting fossil fuels, new markets are appearing for the production and use of alternative transport fuels, such as liquid biofuels. Due to an interconnected global economy, such markets today are developing on a global scale with actors looking to meet local as well as potential international demand. The aim of this paper is to describe and evaluate the emergence of markets for liquid biofuels in Argentina. It reveals that biodiesel production for international supply is likely to emerge in the short run (up to 2010), giving the opportunity to be switched back to local supply in the medium run (post-2010). It also suggests that a bioethanol market (demand and supply) does not seem to be likely in the short run, and it is highly uncertain in the medium run as the most influential actors oppose its development. On the other hand, the current constellations of the biodiesel market appear to leave many uncertainties regarding its sustainability, especially in regard to a limited role of small and medium sized enterprises, and a suitable and diversified biodiesel feedstock. Currently, the focus lies solely on (very) large-scale production of biodiesel derived from soybean oil for the export market.     

Integrated biomass energy systems and emissions of carbon dioxide

Electric Power Research Institute (EPRI) and the US Department of Energy (DOE) have been funding a number of case studies under the initiative entitled “Economic Development through Biomass Systems Integration”, with the objective of investigate the feasibility of integrated biomass energy systems, utilizing a dedicated feedstock supply system (DFSS) for energy production. This paper deals with the full fuel cycle for four of these case studies, which have been examined with regard to the emissions of carbon dioxide, CO₂. Although the conversion of biomass to electricity in itself does not emit more CO₂ than is captured by the biomass through photosynthesis, there will be some CO₂ emissions from the DFSS. External energy is required for the production and transportation of the biomass feedstock, and this energy is mainly based on fossil fuels. By using this input energy, CO₂ and other greenhouse gases are emitted. However, by utilizing biomass with fossil fuels as external input fuels, we would get about 10–15 times more electric energy per unit fossil fuel, compared with a 100% coal power system. By introducing a DFSS on former farmland the amount of energy spent for production of crops can be reduced, the amount of fertilizers can be decreased, the soil can be improved and a significant amount of energy will be produced compared with an ordinary farm crop. Compared with traditional coal-based electricity production, the CO₂ emissions are in most cases reduced significantly by as much as 95%. The important conclusion is the great potential for reducing greenhouse gas emissions through the offset of coal by biomass.     

Political,economic and environmental impacts of biomass-based hydrogen

The purpose of this study is to assess the political, economic and environmental impacts of producing hydrogen from biomass. Hydrogen is a promising renewable fuel for transportation and domestic applications. Hydrogen is a secondary form of energy that has to be manufactured like electricity. The promise of hydrogen as an energy carrier that can provide pollution-free, carbon-free power and fuels for buildings, industry, and transport makes it a potentially critical player in our energy future. Currently, most hydrogen is derived from non-renewable resources by steam reforming in which fossil fuels, primarily natural gas, but could in principle be generated from renewable resources such as biomass by gasification. Hydrogen production from fossil fuels is not renewable and produces at least the same amount of CO₂ as the direct combustion of the fossil fuel. The production of hydrogen from biomass has several advantages compared to that of fossil fuels. The major problem in utilization of hydrogen gas as a fuel is its unavailability in nature and the need for inexpensive production methods. Hydrogen production using steam reforming methane is the most economical method among the current commercial processes. These processes use non-renewable energy sources to produce hydrogen and are not sustainable. It is believed that in the future biomass can become an important sustainable source of hydrogen. Several studies have shown that the cost of producing hydrogen from biomass is strongly dependent on the cost of the feedstock. Biomass, in particular, could be a low-cost option for some countries. Therefore, a cost-effective energy-production process could be achieved in which agricultural wastes and various other biomasses are recycled to produce hydrogen economically. Policy interest in moving towards a hydrogen-based economy is rising, largely because converting hydrogen into useable energy can be more efficient than fossil fuels and has the virtue of only producing water as the by-product of the process. Achieving large-scale changes to develop a sustained hydrogen economy requires a large amount of planning and cooperation at national and international alike levels.     

Prospect of biodiesel in Pakistan

Developing countries like Pakistan need continuous supply of cheap energy. It is common fear in today’s world that fossil fuels will be depleted soon. The cost of energy is increasing continuously and is expected to be at its peak by 2050. Many technologically advanced countries are successfully using renewable energy sources for their energy needs, however, they still believe in the importance of fossil fuel. In renewable energy field, Pakistan is using hydropower for energy needs successfully, whereas project regarding solar and wind energy is in progress. Biomass, a renewable energy source, is gaining interest in many researchers because it produces similar type of fuel extracted from crude oil. Energy from biomasses only depends upon the availability of cheap raw material.Biodiesel, which is produced by the reaction of vegetable oil and alcohol, can be used with same or with better performance in diesel engine. It is a clean fuel that causes less environment pollution as compared to petro diesel. High cost and non-continuous supply of vegetable oil is the main hurdle for its general acceptance. Many advanced countries have developed strategy for continuous supply of cheap price energy crops (source of biomass). Biodiesel is the only possible reciprocal to petro diesel or otherwise diesel engine will be useless after the depletion of crude oil.In this study, biodiesel as an energy source has been discussed; this is indigenous diesel engine fuel and is beneficial for our environment, economy, and more importantly will increase the income of our farmers.