Rising geopolitical tensions and high oil prices are continuing to help renewable energy find favour amongst investors and politicians. Yet how much faith should we place in renewables to make up the shortfall in fossil fuels? Can science really solve our energy problems, and which sectors offers the best hope for our energy future?

To help us get to the bottom of this we spoke with energy specialist Dr. Tom Murphy, an associate professor of physics at the University of California. Tom runs the popular energy blog Do the Math which takes an astrophysicist’s-eye view of societal issues relating to energy production, climate change, and economic growth.

In the interview Tom talks about the following:

Why we shouldn’t get too excited over the shale boom

Why resource depletion is a greater threat than climate change

Why Fukushima should not be seen as a reason to abandon nuclear

Why the Keystone XL pipeline may do little to help US energy security

Why renewables have difficulty mitigating a liquid fuels shortage

Why we shouldn’t rely on science to solve our energy problems

Forget fusion and thorium breeders – artificial photosynthesis would be a bigger game changer

Oilprice.com: Whilst you have proven that no renewable energy source can replace fossil fuels on its own. Which source is the most promising for providing cheap, abundant, clean energy?

Tom Murphy: First let me say that I think "proven" is too strong a word. But yes, I have certainly indicated as much. When it comes to cheap, clean, and abundant, I am drawn to solar. I don't care if it's two or three times the cost of fossil fuel energy - that's still cheap. Abundance is unquestionable, and I don't see manufacturing as being inordinately caustic. The fact that I have panels on my roof feeding batteries in my garage only confirms for me the viability of this source of energy. Wind and next-generation nuclear also deserve mention as potential large-scale sources. Yet none of these help directly with a liquid fuels shortage.

Oilprice.com: Bill Gates has stated that innovation in energy can take 50-60 years to take effect. How then do you believe that that the ARPA-E's short term objectives for projects can be helpful for solving current energy problems?

Tom Murphy: I applaud any effort that takes our energy challenge seriously, and gets boots on the ground chasing all manner of ideas. If nothing else, it raises awareness about our predicament. At the same time, I worry about our technofix culture with a tendency to interpret news clips about ARPA-E projects to mean that we have loads of viable solutions in the hopper. Many of the ideas are just batty. And right - to the extent that implantation of innovation can take decades, we may find ourselves in a squeeze - wondering where all those funky news blurbs went.

Oilprice.com: What do you think is the most exciting energy science or energy technology being researched at the moment?

Tom Murphy: As cautious as I am about techno-giddiness, I do have the giggles for artificial photosynthesis. Combining universally available sunlight (in my own backyard) with a liquid fuel that can support personal and commercial transportation on land, sea, and air with minimal changes to infrastructure is too juicy for me to resist. More so than thorium breeders or even fusion, this is a real game-changer. The catch is that our finite periodic table may not avail itself to our wishes. Groups are now shaking the periodic table by its ankles, hoping that some new and unappreciated catalysts clank to the floor. I'm rooting for them, but at the same time advocate not relying on its realization.

Oilprice.com: A recent report stated that replacing all coal based power stations with renewable energy, would not affect climate change, and in fact after 100 years the only difference would be a change of 0.2 degrees Celsius. What are your views on climate change?

Tom Murphy: I see climate change as a serious threat to natural services and species survival, perhaps ultimately having a very negative impact on humanity. But resource depletion trumps climate change for me, because I think this has the potential to effect far more people on a far shorter timescale with far greater certainty. Our economic model is based on growth, setting us on a collision course with nature. When it becomes clear that growth cannot continue, the ramifications can be sudden and severe. So my focus is more on averting the chaos of economic/resource/agriculture/distribution collapse, which stands to wipe out much of what we have accomplished in the fossil fuel age. To the extent that climate change and resource limits are both served by a deliberate and aggressive transition away from fossil fuels, I see a natural alliance. Will it be enough to avert disaster (in climate or human welfare)? Who can know - but I vote that we try real hard.

Oilprice.com: Do you think that the shale gas boom will lead/has led to reduced investment in alternative energy, and could therefore limit the advancement of alternative energy and its mainstream implementation?

Tom Murphy: I do worry about the sentiment that "our problems are solved" based on a very short history of tapping low-hanging shale-gas fruit. David Hughes presented a sobering report to put these claims in perspective. Even though it is clear that shale gas will contribute to our net energy demands in an unanticipated way, I worry that A) extrapolations based on the "gusher" equivalents is risky; B) natural gas is not a direct answer to a liquid fuels shortage; and C) the associated exuberance can stifle the imperative that we have an all-hands-on-deck response to the looming challenges.

Oilprice.com: What are your thoughts on Biofuels? Will they ever be able to compete with fossil fuels? If you were to pick one that you think has the best potential which would it be?

Tom Murphy: The scale of our fossil fuel use prohibits replacement by biofuels at a substantial level. They certainly can and do play a role, which I anticipate will increase with time - up to a point. The energy return on energy invested (EROEI) tends to be pretty poor (less than 10:1) even for the best examples like sugar cane. And it's a heck of a lot of year-in-year-out work to manage harvests - much depending on the increasingly erratic weather. Of the biofuels, I am most intrigued by algae: mainly because it can be grown and moved about as a liquid medium in sealed tubes. That said, I worry about gunking up the works with bio-sludge, the algae contracting disease, and the fact that we have not yet found/created a viable hydrocarbon-excreting critter.

Oilprice.com: Following the Fukushima disaster many have been calling for the end of nuclear power. What are your views? Should we abandon nuclear power? Are we in a position to abandon it?

Tom Murphy: I don't think Fukushima should be seen as a reason to abandon nuclear. True, nuclear has its challenges, its risks, its hazardous wastes. But it's one of the few things we know how to do that can scale. Of course conventional nuclear again stares right down the barrel of limited resources, which is a déjà-vu we would rather not experience. So next-generation concepts - particularly thorium - are preferable. Then again, we are not prepared to execute such schemes this moment, so they are not much help in a near-term crisis. And ultimately, like so many things, nuclear is yet another technique to create electricity. That's not where the pinch will come. I think nuclear will remain part of our energy mix in any case, so I don't think Fukushima spells an end.

Oilprice.com: What are your thoughts on the Keystone XL Pipeline? Is it vital for America's energy security?

Tom Murphy: Canada produces something like 1 million barrels per day (Mbpd) of oil from tar sands. This is about 5% of U.S. demand. Ambitious plans call for 5 Mbpd production, but even this does not amount to half of our current oil imports. So could it play a role in America's energy security? Possibly. Will it guarantee it? Not likely. We should remember that Canada is a separate country. In a global petroleum decline scenario, how much of that oil will Canada sell to the U.S.? How much will China pay for it? How much of this precious lifeblood will Canada decide to keep for themselves? I won't say that I'm opposed to the pipeline, but like every other "solution" out there, it's complicated, and not a crystal clear win.

Oilprice.com: I've come across many comments and articles online about human ingenuity and that we shouldn't be too concerned with peak oil and fossil fuel depletion because our scientists are surely close to an energy breakthrough. Although this thinking is dangerously naive i was hoping to get your opinion on which technology you think is closest to providing this possible breakthrough?

Tom Murphy: I worry about the strength and pervasiveness of faith in science and technology to fix our problems. And I say this as a scientist who is no stranger to high-tech design and development. We deserve better than blind hope that someone somewhere will pull off a transformative energy miracle. Some things peak. We should acknowledge that once our inheritance is spent, we may not live like the kings we want to be. I can hope along with the rest of us that this isn't true. But I don't feel like gambling: I'm the type to cash out when I'm a bit ahead, rather than keep betting my purse that the next hand will hit paydirt. More concretely, I can say that most physicists I meet in departments around the country are not aware of peak oil and associated challenges. Hardly anyone I meet is working on the problem. No one (i.e., funding) has told us this is a real problem that deserves our full attention. And I sense that it would be political suicide to do so. So which technology do I think will save our bacon? Most ideas on the table provide electricity, which does not address our most critical need. As I said before, artificial photosynthesis hits the sweet spot, and batteries are tremendously important. But let's also prepare a plan B that may be less about techno-fixes and more about behaviors and attitudes.

Oilprice.com: Giant batteries the size of a football pitch are being constructed in order to store energy from renewable sources and release it during times of low power production, for a more consistent supply. Do you think this is the future for renewable energy, or would we be better served creating a giant grid, linking many different renewable sources together so that they can cover for each other?

Tom Murphy: Batteries work, we know. I think we absolutely should be gaining experience on the practical issues/economics of giant batteries. Making large-scale storage more practical resolves the single-biggest technical barrier to widespread solar and wind deployment. I am sceptical about giant grids especially the global variety based on the simplistic notion that "It's always sunny somewhere." I am more attracted to resilient local solutions. Transmission loss today tends to be less than 10% on an old, dumb grid. High-voltage DC would reduce this loss somewhat, and the science fiction superconducting grid would eliminate loss (until the inevitable cryogenic failure vaporizes the lines; and let's not ignore the considerable energy investment needed to keep the lines at cryogenic temperatures). On a moderately ambitious scale, a continental grid will reduce the need for storage, but it will not eliminate it. We still benefit from super-sized batteries.

Oilprice.com: What do you think about the idea that it would be more useful improving the efficiency of current power systems, rather than researching new types of energy production?

Tom Murphy: Efficiency is a lovely thing, and it has always been seen as a lovely thing. Because of this, efforts to improve efficiencies of the big stuff like power plants have been continuous. And we have seen improvements at the level of 1% per year. In rare instances, One can get dramatic leaps via co-generation strategies, but that relies on power plants being situated near demand for waste heat. So realistically, I think incremental efficiency improvement does not have nearly enough bite to "solve" our problem, and in any case tends to be limited to factor-of-two level changes even in the long term. We need much more than that, in the end. I have found behavioural modification to be far more effective, achieving factors of 2, 3, 5, etc. in short order without grossly changing lifestyles.

Oilprice.com: Oilprice.com published an article a few months ago on space-based solar plants. Do you think that constructing space-based power plants could be a valuable option in the future?

Tom Murphy: I have to admit to being somewhat baffled by the concept. Why make solar power even more expensive with exorbitant launch costs (which only increases as energy costs increase), placing the equipment in an unserviceable, hostile space environment (cosmic rays, debris) while only gaining a factor of five in night/weather avoidance? The microwave link is no joke either. The required dishes are huge for both diffraction and ground safety reasons. I have just made a detailed post on Do the Math on Spaced based Solar. But let's think about storage, and save ourselves absurd machinations.

Oilprice.com: Despite the rather public failure of Solyndra and other less well known companies investments in green energy are growing. Which sectors would you be willing to invest in and do you feel offer the greatest potential to investors? Wind, solar, wave, geothermal? Or none of the above?

Tom Murphy: I am not myself an investor, but I would surely like to see more funding for battery research and development, and for anything that can synthesize liquid hydrocarbons using a non-fossil input. Investors want to make money, but I'd rather tackle the important problems. Sometimes timescales make these two goals incompatible. Can you make money on wave or geothermal? Possibly. I'll leave that for others to determine. But I'm not too excited about niche solutions, which may distract us from the real prizes - to the extent that they exist.

Oilprice.com: What role do you think the smart grid has to play in the future?

Tom Murphy: I'd sooner have smart people than a smart grid, deciding that it's in our collective interest to scale back energy use at a personal level. Failing that, a smart grid helps distribute demand in such a way that intermittent renewables are more easily accommodated (using energy when it's available). Some things may work well like this, but I don't think this is a realistic way to hide variable energy supply from the consumer. They may be irked that they lose control over when the laundry decides to start - possibly resulting in clothes smelling of mildew, or that they are not present to fold clothes at 2 AM when the dryer is finished. Loss of control may not play well. If, instead, informed people accepted limitations of future energy supplies, and modified their own behaviour accordingly under their own control, we would break the habit of people taking energy for granted: an attitude that the smart grid attempts to preserve. We want greater personal awareness of energy, not less.

Oilprice.com: Cold Fusion (or LENR) has been deemed impossible for many years, yet Andre Rossi claims to have mastered it. However he won't let anyone examine his E-Cat machine, and some believe that it may be a fraud. Where do you stand? Do you believe that he has mastered an "impossible" science, or that the claims of fraud have merit?

Tom Murphy: This appears to be outside the domain of known physics, so I'll not comment further.

Oilprice.com: The Kardashev scale is a method of measuring an advanced civilization's level of technological advancement. A Type I civilization has achieved mastery of the resources of its home planet, Type II of its solar system, and Type III of its galaxy. Whilst just a bit of fun, do you think that in the future, whether it be millennia or eons, we will ever reach Type I or Type II, or do you believe it impossible?

Tom Murphy: I think it is fallacious to think that humans will master the energy flow and resources even of Earth. Successful examples of long-term sustainable living tend to see people living as part of the energy/resource flow, but not as masters of it. We are only good at mastery in our fertile imaginations. The real world tends not to care what we can imagine. Titanic hubris. I would rather see humans try to live in equilibrium with natural services, rather than attempt foolhardy domination. Our attempts thus far are not very impressive: we're failing to hold it all together even now.

Oilprice.com: Popular focus is on the global energy crisis, but an equally important crisis is looming. Rock phosphate is vital for creating fertiliser, which in turn is necessary for producing large quantities of today's food. It is depleting at a rate similar to crude oil, which could soon mean that the world will experience food shortages. How do you believe this problem could be solved? Should more media attention be focussed on the potential food shortage of the future?

Tom Murphy: Sigh. Another problem we must "solve." How about this solution: one billion people on Earth would obviate many of our problems. Any takers? Any acceptable path to this state? The original question does remind us that our problems are numerous. It is no surprise that the phenomenal surge in population and living standards/expectations in the last few hundred years - both a direct consequence of exploiting our fossil fuel inheritance - should be exposing fault lines every which way. Aquifers, soil, forests, fisheries, coral, ice pack, and species counts are in decline. The very simple answer staring us in the face, yet somehow unthinkable, is to consume far fewer resources and aim to reduce population. Hopefully we can do this in a more controlled way than nature may enforce if we ignore the myriad warnings. This "solution" will no doubt offend many, but just because we want to continue growth does not mean we can. We need to take control of our destiny, and that starts with us as individuals. Decide to reduce; mentally abandon the growth paradigm. Let's maximize our chances of preserving our accomplishments by easing off the gas for a bit.

Oilprice.com: Oil companies are mainly driven by the aim of pleasing shareholders, which generally means pursuing large dividends and high share prices. Surely this profit seeking mentality is detrimental to the advancement of green energy technologies, as the companies have little incentive to seriously invest in new types of energy whilst old, cheaper types still exist. What are your views? Is there any way to change this dynamic?

Tom Murphy: I sense that plenty of people are waiting to cash in on green energy, and investment begins to flourish when energy prices soar. But as soon as high energy prices trigger recession, demand flags, prices crash, and the volatility wipes out many green efforts. A year or two of high prices is simply not long enough for a transformation, which takes decades to accomplish. I hope that we can tolerate smoothly and continuously escalating energy prices for conventional sources, but those high prices hurt large segments of the (conventional) economy and self-generate volatility. In principle, governments could "artificially" keep energy prices high enough to maintain the impetus for developing alternatives, pumping the revenue into a national alternative energy infrastructure. But governments are bound by voters who simply don't want sustained high energy prices. I don't know how to evade this dynamic in a functioning democracy, except via education about the challenges we face - including a sober confrontation of the fact that failure is a likely result of our not bucking up to the challenge.

Oilprice.com: How would you best describe the current situation with oil reserves? Do you believe we have reached Peak oil or are pretty close to it?

Tom Murphy: The simple observation that a peak in global discovery in the 1960's must be followed by a peak in production some decades later is unassailable. So we know the decline is coming, as most major oil-producing countries have experienced already. That part is easy, it's the when that is always hard. The fact that the current petroleum production plateau has hardly budged through factor-of-three price fluctuations is very suggestive that no one has spare capacity at the ready. If we can maintain high prices without re-experiencing a spike and crash like we did in 2008, we might see sub-prime production come online fast enough to maintain the plateau. But A) this might not happen, and B) it's not a resumption of production growth. So I would not at all be surprised if a decline makes itself clear by the end of this decade. I, would, on the other hand, be surprised to see a 5% increase of conventional petroleum production over recent (plateau) levels. But in the decline case, volatility, deliberate withholding, recession, unemployment, wars, etc. can stir in enough complexity to hide the physical truth from us for years. Will it be obvious to the world when we pass into the land of inexorable decline?

Thank you Tom for taking the time to speak to us. For those who wish to see more of Tom’s work please take a moment to visit his blog: Do the Math

James Stafford, Editor Oilprice.com

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