Which of the following best explains the advantages these projections provide for the cell?
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Hydrogen and energy have a long shared history – powering the first internal combustion engines over 200 years ago to becoming an integral part of the modern refining industry. It is light, storable, energy-dense, and produces no direct emissions of pollutants or greenhouse gases. But for hydrogen to make a significant contribution to clean energy transitions, it needs to be adopted in sectors where it is almost completely absent, such as transport, buildings and power generation. The Future of Hydrogen provides an extensive and independent survey of hydrogen that lays out where things stand now; the ways in which hydrogen can help to achieve a clean, secure and affordable energy future; and how we can go about realising its potential. Key findingsSupplying hydrogen to industrial users is now a major business around the world. Demand for hydrogen, which has grown more than threefold since 1975, continues to rise – almost entirely supplied from fossil fuels, with 6% of global natural gas and 2% of global coal going to hydrogen production. As a consequence, production of hydrogen is responsible for CO2 emissions of around 830 million tonnes of carbon dioxide per year, equivalent to the CO2 emissions of the United Kingdom and Indonesia combined.
Global demand for pure hydrogen, 1975-2018Open expandThe number of countries with polices that directly support investment in hydrogen technologies is increasing, along with the number of sectors they target. There are around 50 targets, mandates and policy incentives in place today that direct support hydrogen, with the majority focused on transport. Over the past few years, global spending on hydrogen energy research, development and demonstration by national governments has risen, although it remains lower than the peak in 2008.
Current policy support for hydrogen deployment, 2018Open expandHydrogen can be extracted from fossil fuels and biomass, from water, or from a mix of both. Natural gas is currently the primary source of hydrogen production, accounting for around three quarters of the annual global dedicated hydrogen production of around 70 million tonnes. This accounts for about 6% of global natural gas use. Gas is followed by coal, due to its dominant role in China, and a small fraction is produced from from the use of oil and electricity. The production cost of hydrogen from natural gas is influenced by a range of technical and economic factors, with gas prices and capital expenditures being the two most important. Fuel costs are the largest cost component, accounting for between 45% and 75% of production costs. Low gas prices in the Middle East, Russia and North America give rise to some of the lowest hydrogen production costs. Gas importers like Japan, Korea, China and India have to contend with higher gas import prices, and that makes for higher hydrogen production costs.
Hydrogen production costs using natural gas in selected regions, 2018Open expandWhile less than 0.1% of global dedicated hydrogen production today comes from water electrolysis, with declining costs for renewable electricity, in particular from solar PV and wind, there is growing interest in electrolytic hydrogen. Dedicated electricity generation from renewables or nuclear power offers an alternative to the use of grid electricity for hydrogen production. With declining costs for renewable electricity, in particular from solar PV and wind, interest is growing in electrolytic hydrogen and there have been several demonstration projects in recent years. Producing all of today’s dedicated hydrogen output from electricity would result in an electricity demand of 3 600 TWh, more than the total annual electricity generation of the European Union.
Hydrogen production costs by production source, 2018Open expandWith declining costs for solar PV and wind generation, building electrolysers at locations with excellent renewable resource conditions could become a low-cost supply option for hydrogen, even after taking into account the transmission and distribution costs of transporting hydrogen from (often remote) renewables locations to the end-users.
Hydrogen is already widely used in some industries, but it has not yet realised its potential to support clean energy transitions. Ambitious, targeted and near-term action is needed to further overcome barriers and reduce costs. The IEA has identified four value chains that offer springboard opportunities to scale up hydrogen supply and demand, building on existing industries, infrastructure and policies. Governments and other stakeholders will be able to identify which of these offer the most near-term potential in their geographical, industrial and energy system contexts. Regardless of which of these four key opportunities are pursued – or other value chains not listed here – the full policy package of five action areas listed above will be needed. Furthermore, governments – at regional, national or community levels – will benefit from international cooperation with others who are working to drive forward similar markets for hydrogen. Executive summaryThe time is right to tap into hydrogen’s potential to play a key role in a clean, secure and affordable energy future. At the request of the government of Japan under its G20 presidency, the International Energy Agency (IEA) has produced this landmark report to analyse the current state of play for hydrogen and to offer guidance on its future development. The report finds that clean hydrogen is currently enjoying unprecedented political and business momentum, with the number of policies and projects around the world expanding rapidly. It concludes that now is the time to scale up technologies and bring down costs to allow hydrogen to become widely used. The pragmatic and actionable recommendations to governments and industry that are provided will make it possible to take full advantage of this increasing momentum. Hydrogen can help tackle various critical energy challenges. It offers ways to decarbonise a range of sectors – including long-haul transport, chemicals, and iron and steel – where it is proving difficult to meaningfully reduce emissions. It can also help improve air quality and strengthen energy security. Despite very ambitious international climate goals, global energy-related CO2 emissions reached an all time high in 2018. Outdoor air pollution also remains a pressing problem, with around 3 million people dying prematurely each year. Hydrogen is versatile. Technologies already available today enable hydrogen to produce, store, move and use energy in different ways. A wide variety of fuels are able to produce hydrogen, including renewables, nuclear, natural gas, coal and oil. It can be transported as a gas by pipelines or in liquid form by ships, much like liquefied natural gas (LNG). It can be transformed into electricity and methane to power homes and feed industry, and into fuels for cars, trucks, ships and planes. Hydrogen can enable renewables to provide an even greater contribution. It has the potential to help with variable output from renewables, like solar photovoltaics (PV) and wind, whose availability is not always well matched with demand. Hydrogen is one of the leading options for storing energy from renewables and looks promising to be a lowest-cost option for storing electricity over days, weeks or even months. Hydrogen and hydrogen-based fuels can transport energy from renewables over long distances – from regions with abundant solar and wind resources, such as Australia or Latin America, to energy-hungry cities thousands of kilometres away. There have been false starts for hydrogen in the past; this time could be different. The recent successes of solar PV, wind, batteries and electric vehicles have shown that policy and technology innovation have the power to build global clean energy industries. With a global energy sector in flux, the versatility of hydrogen is attracting stronger interest from a diverse group of governments and companies. Support is coming from governments that both import and export energy as well as renewable electricity suppliers, industrial gas producers, electricity and gas utilities, automakers, oil and gas companies, major engineering firms, and cities. Investments in hydrogen can help foster new technological and industrial development in economies around the world, creating skilled jobs. Hydrogen can be used much more widely. Today, hydrogen is used mostly in oil refining and for the production of fertilisers. For it to make a significant contribution to clean energy transitions, it also needs to be adopted in sectors where it is almost completely absent at the moment, such as transport, buildings and power generation. However, clean, widespread use of hydrogen in global energy transitions faces several challenges:
The IEA has identified four near-term opportunities to boost hydrogen on the path towards its clean, widespread use. Focusing on these real-world springboards could help hydrogen achieve the necessary scale to bring down costs and reduce risks for governments and the private sector. While each opportunity has a distinct purpose, all four also mutually reinforce one another.
International co‑operation is vital to accelerate the growth of versatile, clean hydrogen around the world. If governments work to scale up hydrogen in a co‑ordinated way, it can help to spur investments in factories and infrastructure that will bring down costs and enable the sharing of knowledge and best practices. Trade in hydrogen will benefit from common international standards. As the global energy organisation that covers all fuels and all technologies, the IEA will continue to provide rigorous analysis and policy advice to support international co‑operation and to conduct effective tracking of progress in the years ahead. As a roadmap for the future, we are offering seven key recommendations to help governments, companies and others to seize this chance to enable clean hydrogen to fulfil its long-term potential. The IEA’s 7 key recommendations to scale up hydrogen
Additional downloadsWhich of the following best explains the advantage these projections provide for the cells?Which of the following best explains the advantage these projections provide the cell? The projections increase the selectivity of the membrane because the small size of the projections limits the number of transport proteins that can be embedded in the membrane.
Which of the following best explains the advantage These projections provide the cell quizlet?Which of the following best explains the advantages of these projections provide the cell? The projections increase the surface area-to-volume ratio of the cell which allows for more efficient nutrient exchange with the environment.
What evolutionary advantage does compartmentalization of core metabolic processes offer eukaryotes?Compartmentalization of metabolic processes makes eukaryotic cells very efficient and allows them to increase in size. Within the nucleus, are the molecules of DNA, the macromolecules that carry all the genetic and hereditary information of the cell.
Which of the following best explains the difference in ATP production between these two molecules?Based on Figure 1, which of the following best explains the difference in ATP production between these two molecules? B. The electrons of FADH2 are transferred through three complexes of the electron transport chain whereas those of NADH are transferred through all four complexes.
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