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On Busting Big Oil Myths on the Renewable Fuel Standard: Part I
Yep, land area for corn ethanol is pretty hopeless. Cellulosic biofuel (assuming we find a cost effective way to make it, hint, bio-methanol is cheaper) uses a few times less land.
However, if we instead synthesized fuel from renewable electricity (with, say 60% efficiency), fuel from wind power would use 6 times less land than cellulosic biofuel, and solar would use 40 times less land than biofuel.
So what kind of fuel can we synthesize from renewable electricity? Just two: hydrogen (which is very expensive to transport to refueling stations, and expensive to use in a car), and ammonia (which works fine in modified ICEs but is toxic, but likely managable).
Of course, as of today in the US, any fuel made from electricity will not be economically competative with that made from fossil fuel. Fortunately, ammonia is also a fuel that can be made from fossil fuel with carbon capture and sequestration. It's carbon free at the point of use.
On The Renewable Energy Reality Check
Good job summarizing the issues. One that you missed, is hinted at by this, "...we still require decades of basic RD&D before renewable energy hopefully reaches the point ...".
A fundamental pillar of the renewable ideology is that with enough R & D, we can make breakthroughs happen were ever we want them. Many people truely believe that we'll start by making solar power affordable in the daytime in the desert, and inevitably conquor the nighttime/cloudy location problem as well.
People in the sciences realize we can't predict or control where the breakthoughs will happen (with the possible except of computer technology). We still cannot cure the common cold or make anti-gravity boots or make a safe weight loss pill. In technology inovation, we first generate solutions using the available knowledge, then go find the problems that match.
The classic example is that we did not develope the microwave ovens to address shortcomings with older ovens. (it was an accidental discovery in a radar lab).
On Can Solar Energy Keep the Lights On in the UK?
In a world with no cost or land area constraints, certainly solar could do it all. In the real world, the cost would be far out of line with nuclear and fossil fuels.
The methanol from cyanobacterium that you mention is just another aquaculture biofuel. So far, no aquaculture biofuel has proven cost competititve, and all land based biofuel competes for land with food production (biofuels take about two order of magnitude more land than solar power with the same output).
If you want solar, build transmission lines and buy it from the Middle East and North Africa. Good luck finding energy security.
On Can Solar Energy Keep the Lights On in the UK?
Piezo elements are unlikely to displace the highly effective rotating turbines we currently use in large dam hydro (with their 90+ % efficiency).
Piezo has been suggested for run-of-the-river hydro. But since this type of plant has only a small dam or none at all, it is not dispatchable, it cannot supply winter peaking energy, and isn't even an adequate solution to fill-in for solar on cloudy days. Most rivers have their greatest flow during the Spring (when mountain snow caps melt), which (in the US) happens to be the lowest electrical demand of the year, and the high season for wind power.
Run-of-the-river hydro (and therefore piezo hydro) simply has no place in a low-carbon electrical system.
On Can Solar Energy Keep the Lights On in the UK?
The seasonal power peaking market will be one of the tougher ones in which to displace fossil fuel.
One exception is desert climates like the US's Arizona, wherein the mild winters and hot summer lead to annual load peaking close to the solar energy peak.
Much of the US has a double peak, with both a winter and summer increase. These are actually a pretty good fit for nuclear power, since the spring and fall then become good times for re-fueling shutdowns.
Perhaps northern regions (with winter peaking only) will be the main application of natural gas with carbon capture.
On Energy Innovation: “Artificial Leaf” Could Blow Up Fuel Cell Market
These artificial leaf researchers get lots of headlines, but could they really be cost competive with normal solar panels connected to normal electrolysis units? Interconnecting a large area with plumbing for water and hydrogen will like cost more than interconnect with electrical wire. Then there is the giant lead in efficiency that normal PV solar cells have over these new PEC cells.
On Solar and Wind Energy: Value in Restating the Obvious about Renewables
A not-so-obvious disadvantage of putting solar power production in cloudy (low capacity factor) places is that the difficulty of reaching high penetration increases even faster than the cost. The maximum amount of solar power that a grid can accept without costly energy storage is determined by the peak solar output; with lower capacity factor, that limit is reached at a lower average solar output.
Worse yet, in these cloudy locations, concentrating solar power (CSP) works much worse than fixed PV (due to hazy days). Lack of suitability of CSP means that energy storage (hence high capacity factor and high potential penetration) will be much more expensive: thermal energy storage for tower CSP plants is around $0.5/Watt, but pumped-hydro (the cheapest method for PV) tends to be more like $2/Watt and batteries are even more.
On Energy Finance: German Solar Four Times Higher Than Finnish Nuclear Energy
I'm sorry to tell you that as much as you'd like to avoid being exposed to radiation, there is nothing you can do about it. Radiation strikes each of us every second of every day, from sky above of, from the ground below us, and from the food we eat.
Fortunately, it turns out that the tiny doses of radiation that we recieve from the natural world around us (as well as the smaller doses from man-made sources like medical x-rays and nuclear accidents) are somewhere between harmless and beneficial.
Have you ever noticed that in all of the scary stories we hear about the alleged dangers of radiation and nuclear power, we never see a list of fatalities? For fossil fuel accidents, there is always a body count. It turns out that for nuclear accidents, there are generally no fatalities (the notable exception is a group of firefighters who died at Chernobyl).
Judging by real-world fatality measurements, nuclear is the safest form of high penetration energy we have (and don't pretend that any modern society will ever use wind power without backup from dangerous fossil fuels; the world doesn't work that way).
On Energy Finance: German Solar Four Times Higher Than Finnish Nuclear Energy
The notion that the cost of nuclear will go up (faster than inflation) is non-sense. It is an extrapolation from a time when we were adding rigorous new safety regulations and standards and when construction of power plants of all types slowed way down (due to flattening electrical demand), thus, destroying the economy of scale for the newly redesigned nuclear plants.
Times have changed. Nuclear power has a proven track record of being the safest form of high penetration energy production. We don't need to tighten nuclear regulations; we need to make them more cost effective. We have an urgent need to replace all of our fossil fueled electric plants with sustainable replacements; as a result nuclear can once again grow and see cost reduction through economy of scale like renewables.
The new reality is that the cost of wind power has hit bottom (with 282 GWatts deployed world-wide, it is much more mature than Gen III nuclear), and solar will hit bottom very soon. Thereafter both will increase in cost rapidly with market penetration due to the need for expensive energy storage and long distance power transmission.
Dire warnings about high cost of storing nuclear waste also ignore reality. We would be better off spending the money safeguarding the waste from coal plants and solar PV module production (which by the way, will be hazardous forever and are enormously greater in quantity than nuclear waste).
On Are Electric Cars Green? The External Cost of Lithium Batteries
Ok, so maybe there is a non-zero likelihood that a series of breakthroughs will shrink the large cost premium for sustainable DME over much cheaper ammonia.
Note that sustainable DME has the additional barrier to overcome of being a direct competitor to products from fossil fuel companies. Ammonia, in contrast can be a product of fossil fuel companies (at least during a transition period), hence may be less of a lobbying target.
I should clarify that I do not advocate ammonia for use in all gasoline applications. I would exclude lawn mowers and hand-tools, small boats, and snow mobiles (since these applications involve greater risk of human-fuel contact); as well as airplanes and motorcycles (due to weight/volume performance limitations).
Also, we can engineer ammonia handling systems that produce much less consumer contact with the fuel than is common practice with gasoline. Refueling pumps would form a tight seal (as with cng dispensers) and would have a vapor recovery hoods around the nozzle (like California gasoline pumps). Auto mechanics would wear goggles and protective clothing (as well has have special training).
Here is some info on ammonia safety:
Ammonia Safety, Battel - 2006 conf presentation
Quest - Risk Analysis of Gasoline, LPG, and Ammonia - 2009
Here is Olson's summary: "Based on the results of a highly credible comparative quantitative risk analysis (CQRA) and decades of widespread acceptably safe usage of NH3, it is a fact that NH3 would be safer than propane and as safe as gasoline when used as a transportation fuel."
Ammonia Fertilizer Safety - RCI 2005
On Are Electric Cars Green? The External Cost of Lithium Batteries
I can't garantee that ammonia leakage won't be a problem, but I would claim that we can't quantify the issue until we have good data from larger field trials.
However, I would expect that the ammonia leakage into water bodies from widespread transportation use would be very small compared to that produced by agriculture: ammonia is a gas at normal temperatures and pressures and evaporates rapidly if spilled, converting to a lighter-than-air gas which does not accumulate near the ground like gasoline fumes. In contrast, in agriculture, ammonia is injected directly into the ground, where it can disolve in moisture and be trapped there where it can be mobilized by rain. It's worth pointing out that ammonia is sometimes transported by ship over seas and by barge on rivers.
No doubt that DME is a more user-friendly fuel, which is especially important for in-door applications such as cooking. When made from sustainable energy sources (e.g. solar, wind, OTEC, or nuclear), it will be much less efficient and more more expensive per unit energy than ammonia, if the required carbon is obtained sustainably. Currently, CO2 capture from the air is not cost effective, and requires an amount of land almost on the same order of magnitude of as biofuel. Using CO2 captured from fossil fuel combustion (i.e. diverted from the sequestration path) is not sustainable or carbon neutral.
Starting from natural gas, DME is not made directly, but with methanol as an intermediate. Methanol and ammonia have about the same conversion efficiency (from natural gas), then the methanol to DME step adds additional efficiency loss and capital cost.
So even though DME is a great fuel, I don't see the benefits outweighing the cost compared to ammonia in automotive applications (same for trucks, trains, and cargo ships; as well as industrial process heat).
On Can Energy Storage Make Wind and Solar Energy as Reliable as Coal?
I'm continually drawn to the idea that any carbon-free electric grid has to have energy storage, or at least a lot of large-reservoir hydro. But it does seem that storage will have a hard time being cost competitive with natural gas for load following.
I'm inclined to believe that thermal energy storage at nuclear plants could be competitive with pumped-hydro and much more scalable, perhaps $1/Watt for 5 hour, based on what the CSP studies say. Molten salt storage could be used at high temp plants, or mineral oil at light water plants.