mfioretti: renewables*

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  1. The largest uncertainties and limitations of our analysis stem from the assumed values for impacts per unit electric energy produced. However, we emphasize that our results for both prevented mortality and prevented GHG emissions could be substantial underestimates. This is because (among other reasons) our mortality and emission factors are based on analysis of Europe and the US (respectively), and thus neglect the fact that fatal air pollution and GHG emissions from power plants in developing countries are on average substantially higher per unit energy produced than in developed countries.

    Our findings also have important implications for large-scale "fuel switching" to natural gas from coal or from nuclear. Although natural gas burning emits less fatal pollutants and GHGs than coal burning, it is far deadlier than nuclear power, causing about 40 times more deaths per unit electric energy produced (ref. 2).

    Also, such fuel switching is practically guaranteed to worsen the climate problem for several reasons. First, carbon capture and storage is an immature technology and is therefore unlikely to constrain the resulting GHG emissions in the necessary time frame. Second, electricity infrastructure generally has a long lifetime (e.g., fossil fuel power plants typically operate for up to ~50 years). Third, potentially usable natural gas resources (especially unconventional ones like shale gas) are enormous, containing many hundreds to thousands of gigatonnes of carbon (based on ref. 6). For perspective, the atmosphere currently contains ~830 GtC, of which ~200 GtC are from industrial-era fossil fuel burning.

    We conclude that nuclear energy — despite posing several challenges, as do all energy sources (ref. 7) — needs to be retained and significantly expanded in order to avoid or minimize the devastating impacts of unabated climate change and air pollution caused by fossil fuel burning.
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  2. Barry Saxifrage, National Observer, Sep 21 2017 - 12:00

    I read lots of articles these days pointing to the rapid expansion of renewable energy as a reason to be hopeful about our unfolding climate crisis. Unfortunately, the climate doesn't care how many solar panels and wind farms we build.

    What determines our climate fate is how much climate-polluting fossil fuels we decide to burn. Renewables are great but only if they actually replace oil, gas, or coal. Sadly, rising renewables haven't stopped our fossil fuel burn, or our atmosphere's CO2 from continuing to rise. Instead, the new business-as-usual is one in which we keep expanding both renewables and fossil fuels at the same time.

    The best available science says we need climate pollution "reductions of 90 per cent or more between 2040 and 2070." (see International Panel on Climate Change Fifth Assessment report.)

    But the latest energy data clearly shows we aren't reducing fossil fuel burn. Just the opposite. We keep cranking the tap open wider every year. In a recent article, I dug into the latest "BP Statistical Review of World Energy" to illustrate the climate-sobering fossil fuel side of this story:

    Fossil fuel use continues to rise every year
    Fossil fuels continue to supply at least 85 per cent of global energy use
    Oil and gas are expanding more than other energy sources

    After reading that article, Canadian energy expert Dave Hughes pointed me to the equally sobering renewable energy side of the story. Here it is.
    Demand growth swamps renewables

    Hughes notes that while renewable energy is growing, global energy demand is rising much more.
    Global energy demand vs renewables

    To illustrate, I created this new chart on the right from the BP data.

    The orange line shows the increase in global energy demand since 2009.

    Compare all that new demand to the top green line showing the increase in renewable energy. As you can see, renewables expanded only enough to cover about a quarter of new demand.

    In fact, all the expansion of renewables over the last seven years isn't enough to cover even the single-year demand surge of 2010. Sure that was a big year for demand as the world emerged from a global recession. But those last seven years have also been the all-time biggest years ever for renewable energy.

    The situation looks even worse if you don't like the idea of relying on expanding hydropower dams. That's because hydropower expanded more than any other renewable over those years. The lower green line shows the increase from all the non-hydro renewables: wind, solar, biofuels and biomass.

    So, any guesses what filled that huge gap between renewables and demand? Yep.
    Tags: , , by M. Fioretti (2017-09-25)
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  3. Because wind energy comes and goes with the weather, it makes grid operators nervous. But wind forecasting has improved dramatically, giving more confidence to those who need to keep the lights on.

    And, interestingly enough, the requirements for reserve capacity (backup power for when wind power dips) to manage the grid smoothly went down, not up, over the past few years in Texas, despite rapid growth in wind during Governor Perry’s tenure. That is, the costs for managing variability in the grid decreased.

    Why has there been little disruption to the reliability of the Texas grid? Because alongside rapid growth in wind installations was a market transformation in ERCOT. While Secretary Perry was governor, the Texas market went from a coarse, slow market to a fine-tuned, fast market. Innovating the market to one that is dynamic and fully functioning made it easy to include more wind into the system. It’s also a sign of how advanced technologies enable us to reinvent the grid toward one that is cheaper, cleaner and more reliable.
    Figure showing increasing wind in ERCOT and decreasing regulation requirements. The drop in requirements is due to market operational changes. There does not appear to be any correlation with increasing wind and regulation procurements. Juan Andrade, Yingzhang Dong, Ross Baldick

    But there is still more to do – information technology coupled with integrated hardware can help. Consider this: There are 7.7 million smart meters in Texas, most of them residential. We’ve estimated that installing 7 million controllable thermostats for just the households in Texas would cost $2 billion. Residential air conditioning is responsible for about 50 percent of peak demand in Texas in the summer. That means about 30 gigawatts of peak demand in Texas is just from residential air conditioners.

    By dynamically managing our air conditioning loads – that is, adjusting thermostats to lower overall demand without impacting people’s comfort – we could reduce peak demand by 10 to 15 GW. That means we might not need $10 billion to $15 billion worth of power plants. Spending $2 billion to avoid $15 billion is a good deal for consumers. In fact, you could give the thermostat away for free and pay each household $700 for their trouble and it would still be cheaper than any power plant we can build.

    In the end, Secretary Perry has posed good questions. Thankfully, because of lessons learned while he was governor of Texas, we already have answers: despite concerns to the contrary, incorporating wind and solar into the grid along with fast-ramping natural gas, smart market designs and integrated load control systems will lead to a cleaner, cheaper, more reliable grid.
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  4. John Goodenough is 94, and his current work could be the key to Tesla’s future—much as, decades ago, his efforts were an important part of Sony’s era of dominance in portable gadgets. Over the years, Goodenough has scuffled with Warren Buffett, wound up screwed by global patent wars, never got rich off a headline-grabbing initial public offering and defied the American tech industry’s prejudice that says old people can’t innovate.

    Contrast that with the way we celebrate Evan Spiegel, who at 26 is worth $5 billion because he co-created Snapchat, an app that will probably impact humanity over the long run as profoundly as Cap’n Crunch cereal. Maybe.

    Goodenough announced in early March that he and his team at the University of Texas at Austin had invented a glass-based battery that blows away the performance of every previous kind of battery, including lithium-ion batteries—which were invented in the 1980s by…him. So right now, Goodenough’s technology is powering your smartphone, laptop, electric toothbrush, Tesla and any other rechargeable electronic thing you own. Lots of inventors claim they’re working on breakthrough types of batteries. Goodenough is the only one who can also say he’s done it before.
    End of Gas-Powered Cars?

    Goodenough’s new battery can store three times more energy than a comparable lithium-ion battery, according to the very serious Institute of Electrical and Electronic Engineers (IEEE). The new battery also solves some other lithium-ion troubles. Like, it won’t catch fire, so a hoverboard won’t suddenly melt your kid’s Vans as she scoots across the playground. The IEEE also reports that Goodenough’s batteries seem to be able to soak up in minutes as much charge as a lithium-ion battery gets in hours.
    Tags: , by M. Fioretti (2017-03-15)
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  5. 10,000 years ago, a hunter-gatherer needed about 5,000 kcal per day to get by. A New Yorker today, once all the systems, networks and gadgets of modern life are factored in, needs about 300,000 kilocalories a day That’s a difference in energy needed for survival, between simple and complex lives, of 60 times – and rising. Does that sound like a resilient trend?

    The world is not in danger of running completely out of oil. A lot of oil and gas remain in the ground and under the sea. But those reserves cannot drive growth with the same gusto as before. Today’s thermo-industrial economy grew using oil that, if it did not literally gush out of the ground, was easily extracted using oil-powered machines. In 1930, for the investment of one barrel of oil in extraction efforts, 100 barrels of surplus or net energy were obtained for economic use. Since then, that happy ratio has declined ten-fold or more.

    The calamitous decline in net energy is one reason renewables are not the solution. Green energy strategies suffer from an existential flaw: They take ‘global energy needs’ as a given, calculate the quantity of renewable energy sources needed to meet them – and then ignore the fact that it takes energy to obtain energy. In Spain, for example, the Energy Return On Energy Invested (EROI) of their huge solar photovoltaic intallations is a very low 2.45 despite that country’s ideal sunny climate.

    Our capacity to think clearly about energy is further handicapped by driving blind. In most economic activities, the energy that you can measure – such as the electricity used by buildings, or in an industrial process – is only one part of the picture. A new technique called Systems Energy Assessment (SEA) estimates the many energy uses, that businesses rely on, that are hidden. Phil Henshaw, who developed SEA, describes as “dark energy” the four fifths of actual energy useage that conventional metrics fail to count.

    Eighty percent at five percent

    When pressed, technical experts I have spoken to tell me that for our world to be ‘sustainable’ it needs to endure a ‘factor 20 reduction’ in its energy and resource metabolism – to five percent of present levels. At first I believed, doomily, that Factor 20 was beyond reach. Then, by looking outside the industrial world’s tent, I realised that for eighty per cent of the world’s population, five per cent energy is their lived reality today – and it does not always correspond to a worse life.

    Take as an example, healthcare. In Cuba, where food, petrol and oil have been scarce for of 50 years as a consequence of economic blockades, its citizens achieve the same level of health for only five per cent of the health care expenditure of Americans. In Cuba’s five percent system, health and wellbeing are the properties of social ecosystems in which relationships between people in a real-world local context are mutually supportive. Advanced medical treatments are beyond most people’s reach – but they do not suffer worse health outcomes.

    Another example of five per cent systems that sustain life is food. In the industrial world, the ratio of energy inputs to the food system, relative to calories ingested, is 12:1. In cities, up to 40 percent of their ecological impact can be attributed to their food and water systems – the transportation, packaging, storage, preparation and disposal of the things we eat and drink .

    In poor communities, where food is grown and eaten on the spot, the ratio is closer to 1:1.

    My favourite five percent example – a recent one – concerns urban freight. In modern cities, enormous amounts of energy are wasted shipping objects from place to place. An example from The Netherlands: Of the 1,900 vans and trucks that enter the city of Breda (pop: 320,000) each day, less than ten percent of the cargo being delivered really needs to be delivered in a van or truck; 40 percent of van-based deliveries involve just one package. An EU-funded project called CycleLogistics calculates that 50 percent of all parcels delivered in EU cities could be delivered by cargo bike.

    According to ExtraEnergy’s tests over several years, an average pedelec uses an average of 1kWh per 100km in electricity. Once all system costs are included, a cargo cycle can be up to 98 percent cheaper per km than four-wheeled, motorised alternatives. Some e-bikers reckon that electric bikes can have a smaller environmental footprint even than pedal-only bicycles when the energy costs of the food needed to power the rider are added.
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  6. There’s a problem, however. De-growth solves the sustainability challenge by shifting the burden onto a much more challenging issue, which is to design and implement a de-growth economy. Nobody has the slightest hint as to how to render viable a world economy that would be structurally de-growing while ensuring social balance, individual and collective satisfaction, and peace between the large states. Even the slow-growing economy (at a less-than-1% growth rate) that results from my earlier demonstration remains an unsolved challenge, since we still don’t know how to ensure employment, innovation, useful investments, and even democracy at such a low pace of economic growth. Just think back to the social structures and the kinds of international relations that prevailed across the world before industrialization.
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  7. In reality, the only way Trump can keep this promise is to zero out all clean energy research and development (along with all climate science and support for international efforts), which would shut the door on the below-2°C path just as the rest of the world was working together to pry that door open.

    You may consider it unlikely Trump would follow through, but I was at the U.S. Department of Energy working on clean energy when the GOP took back the House in 1995, led by Newt Gingrich. The House GOP had pledged to zero out all clean energy development and deployment programs — and they succeeded in slashing the budget for all the deployment programs.

    The only thing that stopped them from gutting clean energy research and development was a huge push-back by the administration of President Clinton. The more things change, the more they remain the same.
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  8. There are three more reasons why I think an industrial economy like the present-day US-American one solely driven by so-called clean renewable energies– if the idea can at all be materialized –will be neither free from CO2 emission, nor generally pollutions-free, nor sustainable. I have in the past published several texts presenting my reasons for thinking so.8 There is therefore no need to fully repeat them. Here is only a very short gist of my argumentation:
    (1) The "clean energies" (mostly electricity, but also biofuels) may be a little cleaner than energy from fossil fuel sources, but they are not 100 percent emissions-and-pollution-free. For all equipments – solar panels, wind turbines, cables etc. etc. – used at any stage in the process of generating and distributing "clean energies", in fact any kind of energy, are manufactured by means of machines and factories that are driven mainly (though not solely) by either coal-based energy or nuclear energy, which emit CO2 and radioactive particles respectively.
    (2) All protagonists of 100 percent "clean energy" simply assume that solar and wind energy plants yield an amount of net energy – i.e. a surplus over the whole amount of energy that was consumed for manufacturing and building them) – that justifies their commercial deployment. In other words, their EROEI (Energy Return on Energy Invested) is sufficiently positive. But there is considerable doubt about that.8 I shall take up this point once more below.
    (3) They simply ignore the difference, first pointed out in 1978 by Nicholas Georgescu-Roegen9, between feasibility and viability. He maintained till 1994, the year he passed away, that solar-electricity technology was of course feasible, but not viable. Also TCM's Victory Plan2, despite its other merits, contains these last two errors. I shall come back to this point below.
    Tags: , , by M. Fioretti (2016-10-14)
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  9. Replacements for oil need to be profitable and be able to pay taxes, at currently available price levels–low $40s per barrel, or less.

    We need to be careful in aiming for high-tech solutions, because of the complexity they add to the system. High-tech solutions look wonderful, but they are very difficult to evaluate. How much do they really add in costs, when everything is included? How much do they add in debt? How much do they add (or subtract) in tax revenue? What are their indirect effects, such as the need for more education for workers?

    We need to be alert to the possibility that solar PV and most wind energy may be energy sinks, rather than true energy sources. The two hallmarks of providing true net energy to society are (1) being able to provide energy cheaply, and (2) being able to provide tax revenue to support the government. When actually integrated into the electric grid, electricity generated by wind or by solar generally requires subsidies–the opposite of providing tax revenue. Total costs tend to be high because of many unforeseen issues, including improper siting, long-distance transport costs, and costs associated with mitigating intermittency.

    Unless EROI studies are specially tailored (such as this one and this one), they are likely to overstate the benefit of intermittent renewables to the system. This problem is related to the issues discussed in my recent post, Overly Simple Energy-Economy Models Give Misleading Answers. My experience is that researchers tend to overlook the special studies that point out problems. Instead, they rely on the results of meta-analyses of estimates using very narrow boundaries, thus perpetuating the myth that solar PV and wind can somehow save our current economy.
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  10. It is true that you can find a few studies (very few) that look serious (perhaps) and that maintain that PV has a low EROI. However, in a recent study, Bhandari et al. (1)⁠ surveyed 231 articles on photovoltaic technologies, finding that, under average Southern European irradiation, the mean EROI of the most common PV technology (polycrystalline Si) is about 11-12. Other technologies (e.g. CdTe) were found to have even better EROIs. Maybe these values are still lower than those of some fossil fuels, but surely not much lower (if they are lower) and a far cry from the legend of the "EROI smaller than one" that's making the rounds on the Web.

    Then, if you are worried about another common legend, the one that says that PV cells degrade rapidly, think that those of the plant described at the beginning of this article were found to be still working after 30 years of operation, having lost just about 10% of their initial efficiency! In addition, consider that the most common kind of cells use only common elements of the earth's crust: silicon and aluminum (and a little silver, but that's not essential). What more can you ask from a technology that's efficient, sustainable, and long lasting?

    All that doesn't mean that a world powered by renewable energy will come for free. On the contrary, it will take a very large financial effort if we want to create it before it is too late to avoid a climate disaster (quantitative calculations here). But a better world is possible if we really want it.
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