There have been a bunch of exciting new green energy developments that are real breakthroughs that could solve our energy and climate crisis. Or at least they look like they could have been real breakthroughs. Let's get right to it.
The most gamechanging one first. The big problem with generating clean energy is how to store it, because you don't get to decide when the sun is shining. A breakthrough on that:
In a revolutionary leap that could transform solar power from a marginal, boutique alternative into a mainstream energy source, MIT researchers have overcome a major barrier to large-scale solar power: storing energy for use when the sun doesn't shine.
Until now, solar power has been a daytime-only energy source, because storing extra solar energy for later use is prohibitively expensive and grossly inefficient. With today's announcement, MIT researchers have hit upon a simple, inexpensive, highly efficient process for storing solar energy.
Requiring nothing but abundant, non-toxic natural materials, this discovery could unlock the most potent, carbon-free energy source of all: the sun. "This is the nirvana of what we've been talking about for years," said MIT's Daniel Nocera, the Henry Dreyfus Professor of Energy at MIT and senior author of a paper describing the work in the July 31 issue of Science. "Solar power has always been a limited, far-off solution. Now we can seriously think about solar power as unlimited and soon."
But not all systems are perfectly efficient and many waste heat in a variety of ways. A breakthrough on that solves that problem:
An MIT scientist and a colleague have invented a semiconductor technology that could allow efficient, affordable production of electricity from a variety of energy sources--including waste heat--without a turbine or similar generator... The new technology could have major implications for the recovery of waste heat from power plants and automobiles.
Many researchers have worked to convert heat to electricity directly without using the moving parts of a generator. Among other advantages, such a device would be virtually silent, vibration-free and low in maintenance costs. Until now, however, the efficiency of such devices has been a problem. The amount of electricity they produce from a given amount of energy has been low.
There's been talk about getting off of foreign oil, but year after year, president after president we still rely upon oil that's pumped out of the ground all over the world and shipped in by the millions of barrels per day. This invention can solve that problem by creating biofuel in an ingenous way:
MIT engineers and colleagues are perfecting a device that could turn that foodstuff and various "biocrude" oils into fuel that could reduce the nation's dependence on foreign oil and decrease emissions of the greenhouse gas carbon dioxide. The same device could also significantly reduce the amount of smog-producing pollutants generated by vehicles running on traditional fuels.
All that from a contraption the researchers believe will be relatively inexpensive--only a few percent of the cost of a car or truck. They also believe that it could be introduced into present vehicle technology with only minor modifications, and that it will only need to be replaced a few times over the lifetime of a vehicle.
Essentially the device, which is about the size of a large soup can, works as an onboard "oil refinery." It converts a wide variety of fuels into high-quality hydrogen-rich gas.
We think of oil rigs as bad things. And they are. But what about using them as an inspiration to design something new that can provide tons of clean energy? To not leave wind power out, there was a cool new idea they developed using oil rigs as inspiration.
An MIT researcher has a vision: Four hundred huge offshore wind turbines are providing onshore customers with enough electricity to power several hundred thousand homes, and nobody standing onshore can see them. The trick? The wind turbines are floating on platforms a hundred miles out to sea, where the winds are strong and steady.
Paul D. Sclavounos, a professor of mechanical engineering and naval architecture, has spent decades designing and analyzing large floating structures for deep-sea oil and gas exploration. Observing the wind-farm controversies, he thought, "Wait a minute. Why can't we simply take those windmills and put them on floaters and move them farther offshore, where there's plenty of space and lots of wind?"
...he and his MIT colleagues teamed up with wind-turbine experts from the National Renewable Energy Laboratory (NREL) to integrate a wind turbine with a floater.
Ok, an update. If you look up these stories, you'll note that they're from at least a few years ago, and one of them is from 15 years ago. We've been seeing stories like them for years. Has anything changed? Not really: that's my worry here.
The problem is that there's a combination of a desperate hope for solutions to the global energy and climate predicament, and an interest in those who make small steps from overstating their case. Nobody likes to hear the hard news that small research breakthroughs, while absolutely valuable and worth pursuing, do very little in the scheme of things. So I'm torn. I'd like to see these things happen, but time is ticking away...
This raises a challenge for the community - both of researchers and of people who want to see climate and energy solutions: it's up to us to realistically evaluate the options we have now, and if these research projects come through, then they come through, but we should be prepared for them not to.
Let's look at what we'd need to overcome to get these research ideas to the real world. It's all do-able, but it's hard, and it's why we haven't seen it happen quite yet. Here's a bit I wrote about it a long time ago:
I'm going to survey the challenges for alternative energy David Fridley's excellent article considers in turn.
First, Fridley points out that there are two broad classes of alternatives:
"Alternative energy" generally falls into two categories:
- Substitutes for existing petroleum liquids (ethanol, biodiesel, biobutanol, dimethyl ether, coal-to-liquids, tar sands, oil shale), both from biomass and fossil feedstocks.
- Alternatives for the generation of electric power, including power-storage technologies (wind, solar photovoltaics, solar thermal, tidal, biomass, fuel cells, batteries).
The pitfalls alternatives face are as follows:
1. Scalability and Timing.
For the promise of an alternative energy source to be achieved, it must be supplied in the time frame needed, in the volume needed, and at a reasonable cost.
Fridley goes on to observe how many alternative energy projects currently hailed as great options are only producing on a small scale - not nearly at the scale of production required. Timing is important as well - many of these production facilities, while they're scaling up fast, will still take decades to reach the production capacity that we'd need today if we're to make a transition in time.
Closely related to the issue of scalability and timing is commercialization, or the question of how far away a proposed alternative energy source stands from being fully commercialized.
Many projects we hear about - especially in the excitable tech press - are often still research projects. Commercializing energy technology typically takes many years if not decades, and building up production capacity to useful levels takes many years more.
Ideally, an alternative energy form would integrate directly into the current energy system as a "drop-in" substitute for an existing form without requiring fur- ther infrastructure changes. This is rarely the case, and the lack of substitutability is particularly pronounced in the case of the electrification of transportation, such as with electric vehicles.
Almost none of the alternatives typically discussed provides a dense liquid fuel substitute for oil that can be used in transportation or agriculture. The net-energy-positive alternative that does - algae-based biofuel - is extremely far from commercial viability and requires even more land area per unit energy than corn-based ethanol.
4. Material Input Requirements.
Unlike what is generally assumed, the input to an alter- native energy process is not money per se: It is resources and energy, and the type and volume of the resources and energy needed may in turn limit the scalability and affect the cost and feasibility of an alternative.
Given the scarcity of rare earths and other minerals that go into manufacturing of solar PV, wind turbines, etc. Fridley points out that if we were to scale up production even at the rate currently projected today (not even the rate that we actually would need to make a transition to alternatives), we'd be well beyond the supply of these minerals. Also, fossil fuels are currently providing an invisible energy subsidy to alternative energy production, and that subsidy will steadily go away as oil depletes.
Modern societies expect that electrons will flow when a switch is flipped, that gas will flow when a knob is turned, and that liquids will flow when the pump handle is squeezed. This system of continuous supply is possible because of our exploitation of large stores of fossil fuels, which are the result of millions of years of intermittent sunlight concentrated into a continuously extractable source of energy.
What happens when the sun isn't shining, the wind isn't blowing, or there's a drought that cripples hydroelectric production?
These aren't insurmountable challenges, but they require a large investment in energy storage, which itself is expensive. (One of the reasons I particularly like solar thermal is that it's the easiest to use for low-tech molten salt storage.)
6. Energy Density.
The consequence of low energy density is that larger amounts of material or resources are needed to provide the same amount of energy as a denser material or fuel. Many alternative energies and storage technologies are characterized by low energy densities, and their deployment will result in higher levels of resource consumption.
Nothing comes close to liquid fuels.
Water ranks with energy as a potential source of con- flict among peoples and nations, but a number of alternative energy sources, primarily biomass-based energy, are large water consumers critically dependent on a dependable water supply.
Fridley considers the water needs of various biofuels and finds that they're far far above what we need for current liquid fuels production per gallon of fuel output. Given that aquifer depletion is bad enough now that it's detectable from space, using biofuels would quickly run into water challenges.
8. The Law of Receding Horizons.
An often-cited metric of the viability of alternatives is the expected break-even cost of the alternative with oil, or the price that crude oil would have to be to make the alternative cost competitive. Underlying this calculation, however, is an assumption that the input costs to alternative energy production would remain static as oil prices rise, thereby providing the economic incentive to development.
In other words, as peak oil exacerbates boom-bust economic cycles and overall puts an end to economic growth, it will be difficult to steadily continue building alternatives despite economic fluctuations. At oil price troughs it will be hard to justify building alternatives due to price, and at peaks the input costs of fossil fuels will make alternatives more expensive than they otherwise would have been. Efforts to mitigate this, such as feed-in tariffs are worth implementing, but it is difficult for governments to always keep their promises on these guarantees.
9. Energy Return on Investment.
The complexity of our economy and society is a func- tion of the amount of net energy we have available. "Net energy" is, simply, the amount of energy remaining after we consume energy to produce energy. Consuming energy to produce energy is unavoidable, but only that which is not consumed to produce energy is available to sustain our industrial, transport, residential, commercial, agricultural, and military activities. The ratio of the amount of energy we put into energy production and the amount of energy we produce is called "energy return on investment" (EROI).
By all indications our biofuel options are well below the needed EROI to make them worthwhile, while alternatives for electricity generation have decent EROI.
In summary, when considering any possible transition program to alternatives, we need to consider all of the above pitfalls and examine how to avoid them. To my knowledge, none of the various proposed transitions to alternatives address them all. But maybe they will in time...how much time do we have, though?
Until next time...