What do I think about Climate Change?

Five years ago, I would say that I completely accepted that Anthropogenic Global Warming (AGW), aka Climate Change, was happening and was disastrous.

My primary reason was awareness of the role of CO2 in reflecting infrared radiation back into the lower atmosphere. I would say that the physics supported the AGW claim, and I still think this is true.

Today I would say that the evidence for impending doom is less persuasive. Still, I have no doubt that AGW is happening, and that it would be desirable to reduce the use of fossil fuels, a transition which is already happening at an amazingly rapid pace.

Apparently my position would lead me to be called a “lukewarmer”.

And why am I still in the oil business?

So why am I in the oil business? Actually I viewed (and still view) the oil business as a dead end, both hopefully and practically. I even gave a lecture on Peak Oil. Many people think the Peak Oil idea has been discredited by the subsequent boom in US shale oil. However, what has really happened is that conventional oil production did hit a peak and is now past it. Shale oil drilling, which uses unconventional drilling technology, requires an enormous expenditure of financial and natural resources, and it is far from clear that it is truly profitable or even breaks even on the basis of energy expended versus energy invested. It is a tribute to the American financial system that it could throw so much money into such a questionable endeavor.

Secondly, I doubt that the actions of a company as small as Brandon will have any effect whatsoever on world oil consumption. Most economic activity still relies on fossil fuels, and will for some years to come. Moving away from that is a laudable goal but not feasible in the short term, at least not until energy storage technology makes substantial advances. So for now I am making money from the oil business, which I can then use to support my family and causes that I believe in.

And what about Climate Change?

Today, I am aware of a few additional facts. One is that the supposed scientific consensus on AGW is not as strong as advertised. Another is that the climate models being used to predict disaster are themselves subject to serious provisos, which aren’t always acknowledged in popular discussion.

Scientific Consensus

There is a claim that 97% of scientists agree that climate change is a crisis. However, this figure was derived by reviewing a set of published papers on climate, of which only a third actually made any assertion about AGW. Of that third, it is indeed true that 97% agreed that man-made global climate change was a serious problem, but reliance on this figure seems to be a reach.

Another consensus claim was apparently based on a questionnaire which asked the following two questions: 1) do you agree that global mean temperature has increased from pre-1800 levels? And 2) do you think that human action is a significant cause of this? Note that 1800 was still in what is called the “Little Ice Age”, so almost no one with access to the facts could or would dispute the first contention. Note also that “a significant cause” is not necessarily a crisis. So claiming consensus on the basis of this questionnaire is pretty meaningless.

Climate Models

The physics of atmosphere and climate is extremely complicated, nonlinear, and not solvable in a direct fashion (the Navier-Stokes equation). Thus it is subject to many approximations; even the best computer models are not yet capable of incorporating detailed simulation at short distances. For linear systems this might not be so bad, but nonlinear systems can encounter so-called butterfly effects, whereby small scale perturbations can cause major differences in outcomes.

Even the relative impact of different greenhouse gases is hard to quantify. For instance, CO2 is usually estimated to comprise about 20% of the total greenhouse effect, but the estimate varies from 9-26%. H2O (vapor) is usually considered to have the most impact, 36-72%, but it varies tremendously dependng on locality.

Clouds are unquestionably very significant but no climate model to date can incorporate clouds other than as a plugin parameter (also called a fudge factor). The problem is that cloud formation is local and non-linear, even though the total cloud cover has a global effect. Current climate models are not able to model events at a scale of less than a few kilometers, and this limitation is critical when looking at clouds.

This article discusses the possibility that cloud formation could be inhibited by warming, creating a runaway effect, but, while it points to significant advances in cloud modeling, it also notes that this is not well handled in climate models to date: https://www.quantamagazine.org/cloud-loss-could-add-8-degrees-to-global-warming-20190225/

A Basic Principle

A basic principle with any data-driven hypothesis is that the data from which the hypothesis is derived cannot properly be used to validate the hypothesis. This perhaps seems obvious: if such data did not fit the hypothesis, the hypothesis would not be proposed in the first place. But it is surprising how often this principle is ignored.

With climate change, the models have been derived to fit past data. Scientists can only claim validation when the model has been used to make predictions, and those predictions have come to pass. We are still very early in this game. When models are adjusted to fit new data, their validation is inherently delayed, by this principle, until future data can be gathered and compared.

Don’t the Fires and Hurricanes Prove the Climate is Warming?

They do suggest it is getting hotter in some areas. But local is not the same as global. Warming of the polar regions is likely to have the most potential for catastrophe, yet we don’t experience it directly so it is back of mind.

Melting of sea ice does not have any effect on sea level, since the ice is floating, and therefore already displaces its own weight. However, such melting will reduce reflection of incident solar energy (albedo). Also, water increases in volume when heated.

The California fires have multiple causes. Among them are poor forest management – a misguided attempt to prevent all fires, even the small ones which are essential to prevent buildup of combustibles on the forest floor. A reason for this is that more people are living out in the sticks, where their homes are at risk even from small fires, because living out there can be cheaper, the scenery is pretty, and it has become more feasible to do so with transportation and information technology.

A recent discovery from tree ring studies is that California has suffered periodic megadroughts in the last 1,200 years. The relatively rainy climate of the recent past may be the exception. The years since 2000 are in the megadrought range.

Hurricane activity is on a larger scale and is more persuasive. However, there are so many factors in the genesis of a hurricane that a simple linear dependence on temperature is not likely.

The press coverage would have you believe that these disasters are the direct result of climate change. While I agree that climate change may exacerbate them, the situation is not that simple at all.

Alternative Energy Sources

Ultimately, I think everyone would agree that we can’t keep pumping CO2 into the atmosphere. Therefore we need to move to alternative sources of energy.

The cleanest are solar and wind, ignoring pollution due to fabrication and installation. It seems clear that the developed world is moving to these at a really surprising and significant pace, especially considering the complexity and interdependency of any energy infrastructure.

The pace doesn’t seem satisfactory to those who are convinced of impending doom. However, intermittency is a huge problem. Energy from solar and wind is by its nature highly intermittent. Our ancestors for most of human history had to deal with the intermittency of sun and wind, but it would be a major adjustment for the modern economy.

The math is pretty simple. You either have a duplicate energy infrastructure capable of supplying full power when intermittent sources are not functional, or you must double the capacity of the infrastructure so as to top up batteries for use in the off hours. Either way, you need to build and maintain infrastructure capable of double the current power, which is economically difficult, because you are still supplying the same amount of power. The only alternative is to double the price charged the consumer.

If you want to maintain a backup infrastructure which is not solar/wind, it will have to be turned off whenever solar/wind are producing. That will make it impossible to amortize. The renewables will seriously reduce any chance of running the backup during peak hours.

It is sometimes suggested that a new national power transmission line infrastructure could be used to balance supply over hundreds of miles. However, there is NIMBY resistance to power lines, which is seeming more reasonable after the recent disastrous California fires. Also, there is only a 3-hour time zone difference between the US coasts, so it hard to see how solar balancing would make enough of a difference.

The US uses about 400,000 MWh of electricity per night hour, so 12 hours of backup storage would be just under 5,000 GWh of storage. For comparison, the state of California currently has about 150,000 MWh of energy storage, mostly pumped hydro (see Appendix). That is only about 3% of the storage required nationally, and the true backup requirement is much larger, since I am talking here about only solar; if some of the renewable source is wind, and the wind doesn’t blow, demand will have to be served from backup even during peak daylight hours.

As noted before, generation capacity must be great enough to both supply daytime use and to top up storage; in other words, renewable generation capacity must be about double the instantaneous capacity required by a source that is available around the clock. Worst case, it must cover winter nights at high latitudes, which means up to 16 hours. There you would need triple the current instantaneous generation capacity.

Battery cost projections are enormous, even though great progress is being made in reducing those costs. Today, a Tesla PowerWall stores 14 kWh and costs around $10k installed. At that price, the current California storage capacity of 150,000 MWh would cost over $100 billion, and as we saw that is only 3% of the total needed nationally, so the total would exceed $3 trillion. Worse, batteries degrade over time and a useful lifetime of 10 years is considered quite good for lithium-ion technology.

Of course the US defense budget is about $690b, so some funding could be freed up if we truly believe it is a crisis, and that renewables+batteries are the only answer. Having to replace those batteries every few years remains a problem.

The other problem with intermittency is that when sun and wind are producing, they may well be producing too much. In the absence of adequate battery backup to absorb that power, you have to either shut down or dump energy. So now you are paying for expensive generation facilities, plus backup, with double or even triple the output capacity of the existing infrastructure, and then you are sometimes shutting it down! Insane.

If you really think doom is impending, there are only two alternatives. One is to go immediately and completely to sun and wind, regardless of energy storage capacity. This implies intermittent supply, with a radical impact on modern life and business; essentially, going back to the way of life prior to fossil fuels, when the rhythm of life and commerce was driven by the capricious availabilty of sun and wind.

Worse, given such intermittency, many households and business will be incentivized to generate their own backup power using fossil-fuel generators. For instance, many owners of electric vehicles plug them in to recharge overnight – what are they to do?

The other option is nuclear. It is the only non-fossil energy source that can handle the full energy needs of the economy without intermittency. If the alternative is doom, even disposal and meltdown risks would have to be considered tolerable.

If someone says to me that AGW is now a crisis, I expect them to also step up to one of these alternatives. Intermittency or nuclear. Anything less says to me they don’t really think it’s a crisis.

Carbon Capture

There actually might be a third alternative: continue using fossil fuel power generation, but carbon capture and sequestrartion (CCS). This technology is very much in the early stages, but if you are absolutely against nuclear, and can’t tolerate intermittency, it may be the only game left.

One problem with CCS is the 2nd Law of Thermodynamics. Captured carbon is in a relatively low entropy state compared to free atmospheric molecules. This implies that carbon capture can’t be achieved without a concomitant increase in global entropy, for example, by generating energy to power the capture process. And that raises the question of where that energy comes from, and how much pollution is released as a side effect of generation. Things need to be measured very carefully to be sure that there is a net reduction.

Electric Vehicles

Consider further the effect of the accelerating transition to all-electric vehicles i.e. purely battery powered, as opposed to hybrids. Human beings will likely continue to be diurnal creatures, so the night-time demand for electricity, to recharge these vehicles, will do nothing but increase. Intermittency, with mostly nocturnal power outages, will not be an option.

Personal vehicles could be recharged opportunistically during daytime hours, as they are not typically in continual use. This is not so for long-haul truck and rail transport. Air transport is also concentrated in daytime, for many reasons including safety; not to mention, long-haul air would require truly revolutionary advances in battery technology.

There is fundamental problem here. Absent nuclear power, fossil fuel power generation will continue to be a major source, and the transition to electric vehicles may paradoxically increase demand for it. At least, centralized power generation is more amenable to carbon capture.

New Designs for Nuclear Power

There are promising developments in this area. The rap on nuclear among Green advocates has gone from safety concerns to expense. Perhaps it became clear that nuclear accidents are very rare and very much over-reported. Far more people have died from the effects of air pollution caused by fossil fuels than have died in nuclear accidents.

So the argument has now become that nuclear power doesn’t pencil out economically (even Rocky Mountain Institute, which I generally support, takes this tack). In the US, there is some truth to this, much of it due to lack of design standardization, and to a contentious licensing process. Before discussing a couple of new solutions, I might refer back to the previous calculation showing the immense cost of moving to dependence on renewables; if climate change must be abated at any cost, this is the alternative, and nuclear power is hardly more costly.

NuScale is a company in Portland OR which has developed (originally with funding from the US DOE) a modular, compact design – the Small Modular Reactor, or SMR. The SMR is built in a factory, rather than on-site, allowing for savings from production efficiency. If you want more power, you chain together multiple modules, making it scalable and again saving on production cost. A 12-module plant developing a net 683 MW has initial costs under $3 billion, and cost would likely go down with mass production. 400,000 MW, the target figure for the entire US, would then cost a maximum $1.75 trillion, compared to $2.5 trillion for a battery storage system alone – and the battery system still needs generation capacity to top it up.

The SMR also incorporates new safety features: for instance, if the power grid completely fails, the control rods drop by gravity into the core, shutting it down.

TerraPower, funded by Bill Gates, has developed a design for what is called the Traveling Wave Reactor (TWR). This reactor design uses a small core of fissile material to seed a reaction in depleted uranium, enriching U238 into Pu239 in-situ. The depleted uranium is currently waste material which presents a long-term storage problem, so the TWR solves that. It also solves the problem of enriching uranium in a prior process, which presents security and non-proliferation issues.

Unlike NuScale, TerraPower is still in the R&D phase. Cost estimates are not available, though it is promising that its primary fuel is material currently viewed as only waste.

Appendix: California Dreaming

by James Temple, MIT Technology Review July 27, 2018

There are issues California can’t afford to ignore for long. The state is already on track to get 50 percent of its electricity from clean sources by 2020, and in August 2018 the legislature passed a bill that would require it to reach 100 percent by 2045. To complicate things, regulators also voted in January of that year to close the state’s last nuclear plant, a carbon-free source that provides 24 percent of PG&E’s energy [note: according to another source, that is 9% of the total California energy mix]. That will leave California heavily reliant on renewable sources to meet its goals.

The Clean Air Task Force, a Boston-based energy policy think tank, found that reaching the 80 percent mark for renewables in California would mean massive amounts of surplus generation during the summer months, requiring 9.6 million megawatt-hours of energy storage. Achieving 100 percent would require 36.3 million.

The state currently has 150,000 megawatt-hours of energy storage in total. (That’s mainly pumped hydroelectric storage, with a small share of batteries.)

Building the level of renewable generation and storage necessary to reach the state’s goals would drive up costs exponentially, from $49 per megawatt-hour of generation at 50 percent to $1,612 at 100 percent.

And that’s assuming lithium-ion batteries will cost roughly a third what they do now.

Similarly, a 2018 study in Energy & Environmental Science found that meeting 80 percent of US electricity demand with wind and solar would require either a nationwide high-speed transmission system, which can balance renewable generation over hundreds of miles, or 12 hours of electricity storage for the whole system (see “Relying on renewables alone significantly inflates the cost of overhauling energy”).

At current prices, a battery storage system of that size would cost more than $2.5 trillion.

Appendix: Greenhouse Gas

How does a greenhouse gas work? In other words, how does a concentration of gas such as CO2 or CH4 actually cause the atmospheric temperature to rise? It turns out there is a surprising amount of misunderstanding of this basic science, and it is common to find outright misstatements in the media.

Solar radiation impinges on the Earth. This radiation is concentrated in the visible light frequencies (surprise: we evolved to see best at the frequencies which are strongest). As it hits the Earth’s surface, some gets reflected; the rest heats up plants, dirt, people, etc, and infrared heat radiation (consisting of photons with wavelengths longer than visible light) is emitted back. In equilibrium, the amount of energy brought in by solar radiation would be equalled by the amount of energy carried away by a combination of reflection and infrared photon emission.

A greenhouse gas is one whose molecules strongly absorb in the infrared region. According to quantum physics, and confirmed by experiment, such absorption is not on a continuous spectrum. Certain energies correspond to differences in internal molecular energy levels, so photons with such energies are absorbed, while other energies are not.

Absorption and emission occur therefore at the same energies. A molecule absorbs a photon, entering an excited state, and then relaxes back to a ground state by re-emission of a photon of the same energy. There is no exact timetable: different molecules will remain excited for different time periods. But eventually (and actually fairly quickly) they will all return to the ground state.

Furthermore, photons carry momentum, and, in the absence of a force, per Newton, momentum is conserved. Therefore, when a photon is absorbed, the molecule acquires momentum. When re-emission takes place, the molecule loses momentum.

Suppose you had a cloud of greenhouse gas somewhere in outer space, far from Earth, and you fired a bunch of infrared photons at it. There would be a lot of interactions, with photons being absorbed and reemitted and the whole thing happening again and again. But one thing is for sure: eventually all the photons would come out the other side of the gas cloud, carrying the same total amount of momentum and energy they originally possessed. There would be no heating of the cloud, because that would imply some energy and momentum lost.

Suppose, instead, your greenhouse gas cloud was in the Earth’s gravitational field. Photons are massless and do not experience gravitational force (at least in Newton’s approximation; per Einstein, they do get deflected by spacetime curvature). But molecules possess mass, and are accelerated downwards by gravity. When a molecule absorbs a photon, that molecule gains momentum away from the planet surface, but it then loses some of that momentum by the action of gravity. So when the molecule re-emits a photon of the same energy, there is less net momentum directed towards outer space.

Thus, the infrared photon flux carrying energy away is reduced. More photons are emitted back towards Earth. There are two equivalent ways to deduce the effect of this:

  1. Those re-emitted photons increase the inbound photon flux which heats up the surface more.
  2. By statistical physics (Black Body theory), the amount of energy emitted by an object is strictly a function of temperature. The erstwhile outgoing energy flux has been reduced by the greenhouse gas absorption process, so it is no longer in equilibrium with the inbound energy flux from solar radiation. Equilibrium energy flux can only be reestablished by an increase in temperature, resulting in an increase in the outbound flux of infrared photons.

There you have it. Gravitational pumping is the key to the greenhouse effect.

(A deduction is that if you fire photons at a greenhouse gas, but the photon flux is perpendicular to the gravitational field, you will not see any greenhouse effect).

Comments are closed.