Sunlight, Sunlight Everywhere

“Water, water everywhere and not a drop to drink.” This famous quote from “The Rime of the Ancient Mariner” expresses the rich irony that the seemingly infinite expanse of water contained in the world’s oceans is undrinkable – that is, not in a form fit for human consumption.

Of course, salt water can be transformed into fresh water through a process called desalination. However, in many instances it simply is not practical to do so. After all, large-scale desalination is a hugely energy-intensive process that depends upon extremely complex infrastructure and delivery systems.

It might surprise the boosters of large-scale solar energy that the difficulties associated with transforming sunlight into electricity are nearly as problematic. Sunlight, like seawater, is nearly infinite. Yet the infrastructure and processes necessary to transform it, store it, and transmit it over long distances in a useable form – that is, as electricity – are complex and costly.

Now if your needs are sufficiently low, there really isn’t any trouble at all. Salt water can be desalinated for very little money if you have a solar still and patience. Or in the case of sunlight, you can simply let the sun do what it does – pound away on the soil and your vegetables will respond by converting that sunlight and water into nutritious food – a neat little trick.

However, if your needs are large and growing and you lack time and energy inputs – just what metastatic cities need most, by the way – salt water and sunlight become much less attractive as feedstocks for drinking water and electricity generation, respectively.

The point is that though seawater and sunlight are both plentiful, the difficulty arises in making them useable for human purposes affordably, with few inputs, in a timely manner, at the scale needed.

Unfortunately, these sorts of limitations are associated with all renewable energy sources. In short, no combination of renewable resources can replace fossil fuels as a source of energy for metastatic cities. Like the Ancient Mariner, We presently find ourselves stranded with “sunlight, sunlight everywhere”, and precious little fit for conversion to electricity affordably.

Of course sunlight has special properties which lends itself to great applications such as heating water, cooking, and so forth. But that’s not the focus of this post. For the last month or so I’ve written about the general drawbacks of technology in realizing sustainability. This week I’m going to explain why renewable energy isn’t the panacea many insular planners believe it to be.

A prominent idea in land use development circles is that energy efficiency and renewable energy comprise the “twin pillars” of a sustainable energy policy. Boosters claim that both strategies must be developed concurrently in order to stabilize and reduce carbon dioxide emissions. They say that efficient energy use is essential to slowing the energy demand growth so that rising clean energy supplies can make deep cuts in fossil fuel use. Without efficiency, renewable energy development can’t catch up, and without quick adoption of renewable energy, efficiency measures will only have a minimal impact on reducing total carbon emissions.

On its face this plan seems reasonable enough, however on closer inspection the laws of the jungle expose its fatal flaws. I’ve already spoken at length about the drawbacks of efficiency.

This week I’m going to lay out a framework by which the shortcomings of renewable energy-related technology can be determined and show how insular planning is committing an egregious error by overestimating the value of the twin pillars approach to sustainability.

When I hear someone talk about “sustainability”, I reflexively work to determine exactly what they propose to sustain. All too often it seems that people discuss sustainability in terms of sustaining the status quo.

Now, it is true that technical advances in renewable sources and greater efficiency can greatly reduce the need for energy. For instance, Amory Lovins, the Chief Scientist of the Rocky Mountain Institute has argued a “factor four” is possible (halving resource demands and environmental loads while doubling GDP).

However, in order to achieve safe levels of carbon emissions (and taking economic growth into consideration), we would need a factor reduction much higher than four, because the economy will be expected to grow many times over during this century. In short, we can’t just solve for the problems of today without considering the steep trajectory of the trends at hand.

What makes the twin pillars concept so seductive is that it comports with our unshakable faith in technological ingenuity as I discussed previously. Another dimension that makes it popular is that it suggests that few big changes in behavior will be required in order to become sustainable: instead of filling up the car with gas, now we can plug the car in overnight; instead of using this lightbulb, now we use that lightbulb.

Indisputably, renewable energy will clearly be central to our energy needs in the future. However, it just won’t be at the scale most people imagine. As James Howard Kunstler says, we won’t be running Disney world and the interstate highway system on renewables.

Any renewable energy initiative must answer the following conditions satisfactorily in order to serve as a workable substitute for diminishing fossil fuels:

Is it widely affordable?
In a capital-scarce future, solutions must be inexpensive. Otherwise, only the very wealthy will have access to them.

Can it be scaled up quickly without new infrastructure?
The construction of new infrastructure is costly both in terms of financial capital and energy. Ideal solutions will require few infrastructure costs (and hence, low embedded energy) and can be distributed quickly and easily.

Is it proven in the field?
Super cool, state of the art technological breakthroughs are not good to anyone if they cannot be demonstrated in real world applications.

Does it have high energy density and EROEI?
Ideal solutions possess a very high energy return on energy investment (EROEI).

Is it reducing consumption?
Ideal solutions do not create additional marginal demand (rising energy consumption in real terms).

Does it have no/low carbon emissions?
Ideal solutions do not contribute to climate change.

Is it safe?
Ideal solutions do not introduce unnecessary risks and satisfy the tenets of the precautionary principle.

Does it have no/low material throughput and waste byproducts?
Ideal solutions don’t use large amounts of resources in their recovery or refinement, or create large amounts of waste (directly or indirectly).

Is it easy to build, maintain, replace?
Ideal solutions are durable, replaceable, readily-available, and transparently-engineered; otherwise, they may be difficult to keep running in a resource and capital-scarce future.

The reason that no renewable energy schemes will work in the way the insular planning community has imagined is because none of them answers all these questions satisfactorily. The main lessons here are that the only substitute for cheap energy is costly energy and it’s always going to be difficult to come up with “sustainable” ways to support an unsustainable lifestyle.

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