Sunday, October 05, 2014

The Ebola Epidemiology They Won't Talk About

Remember the AIDS epidemic?  I mean back when AIDS was Big News in part because it was New and in part because it was actually rapidly spreading during the late 1980s.  Well there was this rumor going around the midwest that "the AIDS epidemic is over".  It was more than a rumor, though; It made it into newspapers -- in particular college newspapers where the rumor's optimism could potentially do the most damage by encouraging sexually active young adults to let down their guard so to speak.

Guess where that rumor started?

The world's most prestigious science magazine:  Nature.

Guess where that rumor ended?


No, really; I ended it.

I won't go through all the details of this bit of history here.  I will, however, focus on the correct arithmetic formulas describing the AIDS epidemic and then proceed to describe a way current "authorities" may be underestimating the dangers of the current, unprecedented, Ebola outbreak.

One of the errors the general public made in thinking about the AIDS epidemic was corrected by May RM, Anderson RM in Transmission dynamics of HIV infection*, Nature. 1987 Mar 12;326(6109):137–142.  That error is to over-simplify the transmission dynamics of the virus.  The oversimplification is to assume that the number of people an infected person will infect is proportional simply to the average number of sexual partnerships per person infected with HIV.  

The actual formula is:

R0 = βcD


R0 = Reproductive rate of the virus ( If > 1 we are in an epidemic.)
D = Duration of infectiousness
β = The odds of transmitting the virus per partnership

So far so good, right? I mean the longer you are infectious the more people you are likely to infect and the more likely you are to infect a given partner, the more people you are likely to infect.

But what about that 'c' up there? Well, here it is in all its complex glory:

c = m + σ²/m


c = The effective average number of partnerships per person over the distribution
m = The average number of partnerships per person over the distribution
σ = The standard deviation in the number of partnerships* per person over the distribution

The big enchilada of epidemiology is determining R0 for a given population. The big enchilada of public health is getting R0 as low as possible -- most urgently below 1 and most desirably 0. One of the things that can make people over-optimistic about R0 is thinking 'c' is 'm' when, in fact, 'c' is bigger than 'm'. Indeed, if σ is large, the smaller 'm' is the bigger 'c' hence R0 is.  

Oh, but its worse than that!  

Did you notice that 'σ' is squared: σ² (aka "variance" in the number of partnerships per person)

You know what that means?

It means "diversity is strength" squared. Strength of the epidemic squared that is!

It is known that during the AIDS epidemic there have been AIDS murders; someone with AIDS simply "loses it" and starts having sex -- deliberately unprotected sex -- with others to infect them. Indeed, AIDS neuropathy may contribute to such serial-killer-by-sex behavior in some cases.

There are people who harbor profound feelings of resentment if not outright hatred of US society. Do you think that number has decreased since 1987 when the above epidemic formulas were derived for AIDS? Has the "diversity" of US society decreased since 1987?

I'll put it this way:

If, on average, one of those serial-killer vectors has Ebola and is able to "scan" enough of the population (say, by boarding a subway and leaving a lot of bodily fluids around) to infect another of those vectors, civilization is in big trouble.

*That was the article that I, in turn, further corrected to end the rumors that "the AIDS epidemic was over".  My correction was merely to the definition of one of the variables -- a correction that was later published by Nature in a quasi-retraction -- that being "the probability of transmission of the HIV per partner contact" vs "the probability of transmission of the HIV per partnership".  A "partnership" is a sexual relationship regardless of the number of sexual acts within that relationship.  As Robert M. May told me in our conversation, the tendency to transmit was more dependent on the particular two people in a relationship than it was on the number of times they had sex.  I know -- its counter-intuitive but that's really what he said.  My suggested change to the formula was to keep "the probability of transmission per partner contact" as the definition of β but to exponentially approach 1 with the number of sex acts. He told me that's not an accurate model of the probability and although I don't understand why, I can accept that he did have the proper background to make that judgement. In any event, his is a better definition of a "hit and run" type of encounter between members of the public in anonymous urban settings, which is the primary problem in the Ebola epidemic.

Monday, May 12, 2014

Exponential Remediation of Civilization's Footprint


"The extinction of the human race will come from its inability to emotionally comprehend the exponential function." - Edward Teller

"The greatest shortcoming of the human race is our inability to understand the exponential function." - Al Bartlett

Below is a first-order (approximate) description of a fast (potentially very fast) doubling time system for remediation of civilization's environmental damage. The fast doubling time drives exponential growth that could, at enormous profit and in under 15 years, drastically reduce civilization's ecological impact while, incidentally, sequestering large amounts of CO2. It is not intended to overcome Dr. Bartlett's accusation that sustainable growth is impossible and cornucopian thinking is "The New Flat Earth Society". It is intended merely to argue that imminent environmental catastrophes may, with appropriate refinements and corrections of the described system, be averted within the time estimated for environmental catastrophes by some of the more pessimistic projections (usually several decades rather than a mere 15 years).

An important principle to keep in mind is that as baseload electricity costs decrease, recycling beats other sources of raw materials. This means that if one is targeting zero environmental footprint, the most compelling path is through lower baseload electric cost simply because recycling is more economical than waste.

Baseload electric generation in the following scenario is the Atmospheric Vortex Engine for six reasons:
  1. The AVE's theory is quite basic and, if located in an environment with low winds, such as the tropical doldrums, quite representative of reality -- hence projections based on it are likely to be sound for the tropical doldrums.
  2. AVE technology is scalable to hundreds of terawatts without significant environmental impact.
  3. The AVE, unique among prospective baseload electric generation systems, is inherently suited to scrubbing the atmosphere of pollutants.
  4. The AVE complements any baseload electric generation systems that produce waste heat (including prospective ones such as cold fusion, thorium breeder, hot fusion, advanced fission, solar collection, etc.) in that only the AVE can reach a virtually limitless heat sink of the very low temperatures required for high Carnot efficiency cogeneration. 
  5. If located in the tropical doldrums and produced by rapid reproduction to macroengineering scales, the projected cost of a kWh of baseload electricity from the AVE, alone, drawing heat only from renewable oceanic heat, is on the order of a few mils (tenths of a cent of a USD) -- 5 mils is a conservatively high figure.
  6. The AVE's primary construction cost is structural materials which, given electric power are economically derived from in situ resources.
Another important principle to keep in mind is that civilization's primary environmental impact is agriculture. The primary objective must be to reduce agriculture's environmental footprint -- where agriculture includes all sources of food to sustain civilized populations including not only land-based agriculture but also exploitation of natural fisheries. Moreover, if you focus on agriculture, you must focus on "primary production" -- the photosynthesis of food calories (proteins, carbohydrates or oils).

Finally, it is important to co-locate human habitats with the primary production systems but this is of no avail if those habitats are not more attractive than current human habitats. People must spontaneously relocate to these systems where their wastes are recycled.

Overview of the Fast Doubling-Time System

The fast doubling time system is a tropical-doldrums, artificial floating atoll, sheltering a low sea state lagoon upon which floats algae photobioreactors of exceedingly high primary production for the food chain. The atoll is produced from in situ resources available in the air and ocean by the application of very low cost baseload electricity generated by an Atmospheric Vortex Engine, the primary structure of which is also produced from the same in situ resources, the electricity for which is from a pre-existing such AVE.

A reference design is based on the 500MW capacity maritime AVE projected by AVE patent-holder, Louis Michaud. The projected per capita electric power use will be 4 times higher than the US at present in order to support total recycling with most energy for industry and transportation derived from electricity. This yields a near-zero environmental-footprint carrying capacity of 100,000 people per atoll.  These 100,000 people enjoy not only beach front lifestyle but also sufficient population and density to substitute for current urban amenities.

The doubling time is potentially on the order of months, with an estimate of 3 months justified below.

A system with a 3 month doubling time could remediate the environmental impact of civilization's 7 billion people in under 15 years.

If you have an emotional reaction against this "outrageous" claim, try to recall the words of Edward Teller and Al Bartlett about human emotions and exponentials (doubling times).

Emotions are no substitute for arithmetic.

The Fast Doubling AVECarbocrete Core

The core of the system is the electric power from the AVE coupled to the Carbocrete production process. Doubling time of the whole system is limited by the doubling time of the AVECarbocrete core because once an AVECarbocrete exists, the rest of the surrounding atoll can be constructed without increasing the doubling time of the system.

Carbocrete(TM) is 75% lighter and more durable than steel reinforced concrete. It is a very good candidate for AVE arenas in general but is particularly well suited for the maritime AVE for a number of reasons, not the least of which is that the electricity from the AVE can be used to manufacture Carbocrete entirely from maritime materials available in the air, seawater and sand from the sea floor (Carbocrete requires 50% less sand than normal concrete and requires no rock aggregates).

The Calera process is a promising* way to create concrete (CaCO3) from electricity, air and sea water. The carbon for the Carbocrete is available from CO2 and can be extracted by a sub-process of the Calera process -- a process in which very high pH media (NaOH) absorbs CO2 either from sea water or from air that is passing over its surface (as would be the case with the AVE). Magnesium is also available from sea water with electric extraction and could form, along with carbon fiber parts, much of the remaining materials of an AVE, such as turbine blades.

The Calera process requires 3.3GJ of electricity to produce one tonne of concrete**. If a system design focused on self-replication (with human labor inputs of course) from in situ materials and AVE electricity, the doubling time of these maritime AVECarbocrete systems could be exceedingly short -- hence the resulting AVE electricity cost brought much lower.

The initial system could be constructed from a floating Calera 500MW input plant designed to be constructed primarily out of Carbocrete from Calera cement reinforced with carbon fiber. To bootstrap the very first AVECarbocrete system, the 500MW input to that Calera plant could be 3 natural gas turbines from GE (GE9281F @ 217MW each and @ $40M each) floating on barges, fueled by LNG ships. These would be rented and the rental costs, paid for out of capital, rapidly amortized by subsequent rapid self-replication of the AVECarbocrete systems.

If we had a rough idea of how many cubic meters of Carbocrete a 500MW maritime arena would require, it would then be straight forward to calculate the amount of time the 500MW maritime AVE would have to run in order to manufacture its own Carbocrete construction materials.

A very rough calculation with some guesses of my own to illustrate how such a calculation would work using Unicalc:

A 200m diameter, 80m high AVE arena might be approximated as a cylinder with two circular "lids" -- all averaging 1ft thickness:

([{pi * (200 * meter)} * {80 * meter}] + [{2 * ([100 * meter]^2)} * pi]) * (1 * foot) ? meter^3
= 34472.067 m^3

So that's the volume of Carbocrete required. Now the time required to produce that Carbocrete given 500MW input to a floating Calera plant given Carbocrete is 2.7tonne/m^3 and it takes 3.3GJ/tonne of Calera concrete (and that approximates the energy to produce the Carbocrete):

(34472.067 m^3/500MW);(2.7tonne/m^3);3.3GJ/tonne?days
([{34472.067 * (meter^3)} / {500 * (mega*watt)}] * [{2.7 * ton_metric} / {meter^3}]) * ([3.3 * {giga*joule}] / ton_metric) ? ...
= 7.1098638 days

This incredibly fast doubling time illustrates that raw materials are the least of our worries. Keep in mind, these constitute the majority of the materials that, otherwise, would need to be transported by ship thousands of miles to the tropical doldrums.

Let's double that amount of Carbocrete to reproduce the floating Calera plant that is paired with each AVE, and double it again to account for inefficiencies and double it again to be on the safe side: we multiply by 2^3 = 8 -- so that's 57 days or about 2 months doubling time for the AVECarbocrete core's construction materials.

A doubling time of 2 months still seems ridiculously fast, but if modern automation and construction techniques, such as concrete printing, are applied, a reasonable argument can be made that the primary structure of this system need not be the limiting factor in reducing the doubling time. Other critical components such as machined parts, electronics, etc. are far smaller and can be transported much more easily from high production volume facilities. Ultimately these, too, would be incorporated into the system but such is not essential.

Lets tack on another 50% for various bottlenecks in the critical path of construction and we have:

Doubling time of 3 months.

Agriculture -- The New Green Revolution

As has been previously discussed, the next green revolution will provide at least a factor of 10 lower area requirement for agriculture, based on floating photobioreactors. These photobioreactors require wave-break shelter from even moderate sea states -- shelter naturally provided in the lagoon of an artificial atoll. In the tropical doldrums the primary production of agricultural feedstocks would be far higher than the annualized 35g/m^2/day measured for more northerly (Mediterranean) climates, but let's stick with 35g/m^2/day to be conservative.

Although the total agricultural system would be aquaponic, yielding high-value produce in symbiosis with high value sea food, let's look only at the sea food protein resulting from a food chain based on a natural species of algae: arthrospira platensis aka "spirulina".

Spirulina consists of better than 50% protein. The trophic loss in fish aquaculture is approximately 2 to 1 -- or about 2 units of feed for 1 unit of fish. Lets further say that an additional factor of 4 is required to provide a wide array of kinds of sea food -- not just algae grazers like tilapia and sockeye salmon -- including predator fish as well as invertebrates such as mollusks, crab, lobsters, shrimp, etc. Each square meter of photobioreactor's primary production of algae is therefore reduced by a factor of 16 (50%*(1/2)*(1/4)) before it is consumed by humans. Each square meter therefore produces a little over 2 grams per day of human consumable food.

How big must the lagoon be to support the atoll's population?

Well, first we need to know how big the atoll's population would be and for that, we need to look at the per capital electricity consumption of the 500MW AVE capacity. Since we are positing electricity-intensive infrastructure for all energy needs, including replacing most raw materials with recycled materials, let's increase the per capita electric consumption by a factor of 4 over the current US per capita electric consumption.

Each 500MW AVE could support a population of 100,000 people.

If that 100,000 people needed to consume 1lb of protein equivalent per day (remember we aren't including fruits and vegetables that would be hydroponically produced in conjunction with the sea food production of the aquaponics system), then the photobioreactor area, hence the lagoon area, would need to be about:

([{(2 * gramm) / (meter^2)} / day]^-1 * [{(1 * poundm) / person} / day]) * (100000 * person) ? (kilo*meter)^2
= 22.6796 (km)^2
or about 23 square kilometers.

Assuming the atoll is perfectly circular, that represents a radius of:

sqrt((23 * [{kilo*meter}^2]) / pi) ? kilo*meter
= 2.7057582 km

So the atoll has a diameter of about 6km.

Closing the Deal With Tropical Beachfront Real Estate

A 6km diameter represents a potential of:

pi * (6 * [kilo*meter]) ? meter
= 18849.556 m

or about 20,000 meters of beach front real estate.

Recalling that each atoll's population is about 100,000 people, that yields population density of about 5 per meter. This indicates a high-rise condominium beach front, as with Miami Beach. People have shown a clear preference for these kinds of urban beachfront environments.

Let's therefore stick with that figure and calculate how many stories of family-of-four condominiums averaging 4000ft^2 each with 40ft of beachfront would be needed to accommodate this 5 people per beachfront meter population density.  First, lets calculate how many people must be stacked on a 40ft beachfront to achieve 5people per meter:

([5 * people] / meter) * (40 * foot) ? people
= 60.96 people

Now let's calculate how many stories this requires at one home per story:

60.96 people/(4people/story)?story
(60.96 * people) / ([4 * people] / story) ? story
= 15.24 story

Or about 16 stories in our beachfront condo.

Comparable condominium complexes in Miami Beach go for on the order of $3 million for each condo.

Obviously, this is price, not cost of these beachfront condominiums -- and it is only the price for early units. However, if it were possible to sell these condos for $3 million each, the real estate value, alone, of the atoll would dwarf its food production value, let alone the electric generation.

([100000 * people] * [{3E6 * usd} / home]) * ([4 * people] / home)^-1 ? usd
= 7.5E10 usd

or about $75 billion.

The food at approximately $300/person/month with a 12% zero amortization schedule has a present value of approximately:

([{(100000 * people) * (300 * usd)} / people] / month) * (100 * month) ? usd
= 3E9 usd

or $3 billion.

The electricity at approximately 5mil/kWh with a 12% zero amortization schedule has a present value of approximately:

([{0.005 * usd} / {kilo*Wh}] * [500 * {mega*watt}]) * (100 * month) ? usd
= 1.825E8 usd

In other words, the value of the early atolls is dominated by their real estate value, with food value coming in second and electricity value negligible.

Now lets figure how long it would take for an AVECarbocrete core to produce the Carbocrete for these beachfront condos.

Let's say we want the 16 story condos to rest on a flotation platform that extends the beach 200 feet to the water and another 200 feet beyond that for the breakwater. We'll let the lagoon-side terminate at only 100 feet. With the condos being 100ft in radial length, we have a total of 200ft+200ft+100ft+100ft of flotation platform in radial dimension. Since the condo's weight determines the amount of water displaced to float it, we'll estimate that first:

([{(40 * foot) + (100 * foot)} * {12 * foot}] + [{100 * foot} * {100 * foot}]) * (1 * foot) ? meter^3
= 330.74077 m^3

or about 400 cubic meters of Carbocrete per condominium with stories each 12 feet high and 1ft thick walls and ceilings/floors that are shared with adjacent condos.

The volume of Carbocrete per length of beachfront per condo is then:

(1000 * [meter^3]) / (100 * foot) ? (meter^3) / foot
= 10 m^3/ft

And for 16 stories it is  obviously 160 m^3/(ft beachfront).

Given a Carbocrete density of 2.7tonne/m^3 we have:

160m^3/(ft beachfront);2.7tonne/m^3?tonne/(m beachfront)
([160 * {meter^3}] / [foot * beachfront]) * ([2.7 * ton_metric] / [meter^3]) ? ton_metric / (meter * beachfront)
= 1417.3228 tonne/(m beachfront)

That means the flotation platform has to displace approximately 1500m^3 of ocean water for each meter of beachfront.

Keeping in mind the 200ft+200ft+100ft+100ft of flotation platform in radial dimension, to displace that 1500m^3 per meter of ocean water we need:

([{(200 * foot) + (200 * foot)} + {100 * foot}] + [100 * foot])^-1 * ([1500 * {meter^3}] / meter) ? meter
= 8.2020997 m

or about 10 meters of air space below water for the entire radial length of the platform.

That means the flotation hull has to have a Carbocrete perimeter in the atoll's radial dimension of about:

([{([200 * foot] + [200 * foot]) + (100 * foot)} + {100 * foot}] + [10 * meter]) * 2 ? meter
= 385.76 m

or about 400m (0.4 a kilometer).

Assuming this flotation vessel averages about 1ft thick the mass per beachfront length of the flotation hull is about:

([{1 * foot} * {400 * meter}] * [2.7 * ton_metric]) / (meter^3) ? ton_metric / meter
= 329.184 tonne/m

Adding that to the condominium's mass we have:

1417.3228 tonne/m+329.184 tonne/m?tonne/m
([1417.3228 * ton_metric] / meter) + ([329.184 * ton_metric] / meter) ? ton_metric / meter
= 1746.5068 tonne/m

or about 2000tonne/m of Carbocrete per meter of beachfront real estate.

How rapidly, then, can our 500MW AVECarbocrete core produce this?

([{3.3 * (giga*joule)} / ton_metric]^-1 * [500 * {mega*watt}]) * ([2000 * ton_metric] / meter)^-1 ? meter / day
= 6.5454545 m/day

or about 6m of beachfront real estate per day per AVECarbocrete core.

How long would it take to complete the atoll?
20000(m beachfront)/(6m beachfront/day)?years
(20000 * [meter * beachfront]) / ([{6 * meter} * beachfront] / day) ? year
= 9.1324201 years

or about a 10 years to complete an atoll once its AVECarbocrete core is producing its Carbocrete.

(At this point please note that it is likely feasible*** to build more than one 500MW AVECarbocrete core by diverting early Carbocrete, that would ordinarily go into the atoll, toward constructing at least one more AVECarbocrete core.  This would bring the atoll completion time to 5 years instead of 10.)

Obviously there is a limited market for $3million condos, and 10 years is a long construction time, but, with automation brought on by industrial learning curve, the cost of beachfront condo real estate approaches the limit imposed by the cost of producing the materials which, by that time, is the levelized marginal cost of another AVECarbocrete core. 

A condominium has a material requirement (including flotation) of:

([2000 * ton_metric] / meter) * ([40 * foot] / [40 * condo]) ? ton_metric / condo
= 609.6 tonne/condo

At 5mil/kWh this costs:

3.3GJ/tonne; 609.6tonne/condo;0.005usd/kWh?usd/condo
([{3.3 * (giga*joule)} / ton_metric] * [{609.6 * ton_metric} / condo]) * ([0.005 * usd] / [kilo*Wh]) ? usd / condo
= 2794 usd/condo

or about $3000 per family of four.

So How Do You Get To World Salvation In 15 Years???

Here's how:

Each AVECarbocrete core grows into an atoll supporting 100,000 people.  The time it takes to exponentially reproduce the number of AVECarbocrete cores for 7 billion people is:

100000people*2^doublings = 7e9people
doublings  = log2(7e9people/100000people)
doublings = log(7e9people/100000people)/log(2)
= 16.095067 doublings

And, as we recall, the doubling time for the AVECarbocrete core was 3months, which means:

16.095067 doublings;3month/doubling?years
(16.095067 * doublings) * ([3 * month] / doublings) ? year
= 4.0237668 years

Or under 5 years until the last AVECarbocrete core produced starts on constructing its atoll which, as we saw previously, takes 10 years to complete.

5 years plus 10 years is, through the miracle of addition:

15 years.

*The Calera process has to dispose of chlorine evolved during electrolysis of sea salt.  This is a serious environmental issue that will be addressed in a future article.  Considerations are  1) that the estimated US capacity, alone, for CO2 geologic sequestration is greater than that which would be required to sequester all of the chlorine resulting from the global scale of this project -- a project which not only sequesters virtually the same amount of CO2, but terminates further CO2 emissions, while restoring natural carbon sinks such as rainforests, 2) CPVC/carbon fiber/CaCO3/MgOH2 composites have shown properties superior to fiberglass, and the majority of the mass of such composites is chlorine -- a fact that could radically change the in situ structural materials approach so as to de-emphasize the Calera process and emphasize scrubbing CO2 directly from the air by recycled NaOH rather than liberating Cl2 from CaCl2.  This would radically reduce the amount of chlorine produced while using what little is produced as structural mass, 3) Chlorine in the troposphere -- usually derived from photochemical separation of oceanic NaCl -- is a major sink for methane and methane is 25 times more potent as a greenhouse gas than is CO2.

**See footnote at Greenhouses Are Not the Next Green Revolution.  The cost of deep sea dredging for sand is assumed to be similar to the energy cost of synthesizing CaCO3.

***The feasibility of additional AVECarbocrete cores per atoll is limited by the thermal flow from the surrounding ocean water pulled in by downward convection of cooled water expelled from the AVE.  It is reasonable to posit at least two 500MW AVECarbocrete cores would have the requisite heat flow because the vast majority of the incident solar energy is absorbed by the floating photobioreactors, which are only about 5% efficient in turning solar energy to food energy.  That means 95% of the insolation would be available as heat flow colocated with the AVECarbocrete cores.  That amount of solar thermal power is:

(23 * [{kilo*meter}^2]) * ([300 * watt] / [meter^2]) ? mega*watt
= 6900 MW

Or nearly 7GW, whereas the output of the AVE is 0.5GW -- and that the Carnot efficiency of the 500MW AVE is estimated to be 12% which means even without resorting to inward flow of ocean water outside of the atoll, the electric power available is:

(12 * percent) * (7 * [giga*watt]) ? mega*watt
= 840 MW

So we are very close to the 1000MW for two 500MW AVECarbocrete cores per atoll.

Monday, May 05, 2014

Greenhouses Are Not the Next Green Revolution

Before I explain why greenhouses are not the next green revolution, let me tell you about the next green revolution.

Why am I doing it in this order? 

Because whenever I tell people about the next green revolution, there is always some militant ignoramus who pipes up with something about "vertical gardening" or some other greenhouse based technology and they absolutely refuse to sit down with me and run through the basic arithmetic. That is why I'm writing this.

The Next Green Revolution: The Algae6 Photobioreactor

The next green revolution will reduce agriculture’s footprint by a factor of 10 while increasing protein yields to the point that the entire planet’s population can have a diet as high in calories and protein as the US diet (even going through trophic loss in aquaculture food chains), decreasing fresh water usage by a factor of 10, decreasing greenhouse gas emissions and rewilding the Amazon basin’s soybean fields and other rainforests now being denuded for palm oil. That revolution is here: The Alga6 photobioreactor from Algasol, LLC brings the cost per insolated area below that for open ponds while yielding areal productivity at an annualized rate exceeding 35g/m^2/day using natural algae strains in high insolation desert areas, with a dry-biomass concentration greater than 12g/liter (critical for operational expense).

You haven’t heard of this because although Algasol sold thousands of its PBRs, it had to shut down production due to the strict labor laws in Spain coincident with the financial crisis, and is just now restarting a showcase under the auspices of the University of Majorca, which has the requisite labor relations.

The ideal environment for this PBR is floating on saline water. Deployment in the equatorial ocean desert doldrums is its ultimate destination — a location with much higher insolation and therefore much higher areal productivity potential, bringing the potential agricultural foot print of civilization to arbitrarily low levels.

When agriculture relocates to the ocean deserts, it makes sense to relocate population there as well — particularly if it is feasible to provide beach-front property via artificial floating atolls -- circular islands with interior lagoons.  The lagoons would have low enough sea state to provide an ideal environment for floating photobioreactors, rendering the atolls food exporters as well as population centers.  The demand for beach-front property is well established at thousands of dollars per ocean-facing foot.  Even so, the production of the atolls with beaches requires advances in energy technology that may be uniquely available in the tropical oceans.  See my prior blog entry on the Atmospheric Vortex Engine which is particularly well suited for the tropical doldrums.  In combination with the Calera process (requring 3.3GJ/tonne concrete*), the AVE can produce very inexpensive concrete from the heat collected by the photobioreactors, converted to electricity that is applied to elements available in sea water (calcium) and air (CO2).  With such technology beachfront property on artificial floating atolls could be manufactured for a small fraction of its real estate value.  With industrial learning curve, the cost of beachfront property may become affordable for virtually the entire population of the developed world.   These calculations will appear in a future article.**

An Interim Message To Aspiring Environmentalists

Rational environmental concern must favor technologies that out-compete existing technologies that have a larger ecological footprint. Any rational measure of ecological footprint must take into account the amount of biodiversity that is disrupted — not just physical size. For example, if a technology existed that would allow one to cultivate soybeans more profitably on the same amount of land in a desert as in a cleared portion of the Amazon rainforest, opposing it out of environmental concern would be irrational.

The tragedy befalling the environmental movement is that the majority of self-proclaimed “environmentalists” don’t care about the environment in this rational way.

The open ocean has places with far lower biodiversity than coastal ecosystems. If, for example, an open ocean aquaculture technology pollutes to the same degree as current aquaculture techniques that utilize coastal areas, but is more profitable, then it should be seen as an environmental good.

One would prefer to move these aquaculture operations to the so-called “ocean deserts”. If there were a technology that attracted them to that location, then that, too, would be an environmental good — all else being equal. That's where the Alga6 PBR comes in;  but do keep in mind that all else is not equal with the Alga6:

The Alga6 dramatically reduces the amount of area required for primary protein and oils production compared to the Amazon soybean fields or palm oil fields of Indonesia.

Truly those successfully opposing such technologies are doing more harm to the environment than the big corporations they decry.

Some Basic Arithmetic For Greenhouse Advocates

Dutch greenhouse technology has the highest productivity per area of any greenhouse technology, at 90lbs of tomatoes per square meter per year.  This is so far beyond the productivity of ordinary agriculture that it is easy to see why people would believe this to be the next green revolution.

In our arithmetic demonstrating the Alga6 beats Dutch greenhouse technology, we will ignore the cost of constructing the Dutch greenhouse as well as the electrical cost of artificial light and other operational expenses.

Fair enough?  You do understand, don't you, that by ignoring these costs we are giving greenhouses a running head start -- placing a handicap on the Alga6 in this comparison  (because the Alga6 has a much lower cost of construction and uses natural light)?

Now, the first thing you have to understand about agriculture is that the primary need for food is energy.  The vast majority of food mass you eat is either discarded or burned up to power the body.  Average humans burn energy at about the same rate as a 100W lightbulb.  That's even if they don't lead a particularly active life.  The brain alone burns about 20W without straining itself.  

That means people need to eat food at a rate of about 100W of power.

Now let's calculate how much power, in food watts, is produced per square meter of an artificially lighted Dutch greenhouse:

([{90 * poundm} / {meter^2}] / year) * ([22 * {kilo*calorie}] / [123 * gramm]) ? watt / (meter^2)
= 0.96939567 W/m^2

or about 1 watt of food power per square meter of greenhouse technology.

What did I just do there?  

Its pretty simple when you use the Unicalc calculator, as I did:

Dutch greenhouse technology produces about 90lbs of tomatoes per square meter in one year.  Tomatoes have an energy content of about 22 food calories (or 22 "kilocalories") per 123g.  Unicalc has the conversion factors and knows how to multiply and divide quantities given their units.  It makes doing calculations like this a snap and through the miracle of arithmetic we can discover wonderful things like what will work, what won't and even what is best.

Now lets look at the Alga6's production of food power per square meter:

([{35 * gramm} / {meter^2}] / day) * ([410 * {kilo*calorie}] / [100 * gramm]) ? watt / (meter^2)
= 6.9537708 W/m^2

or about 7 watts per square meter of food power.

Now let me make this as plain as I can:

The Algae6 does 7 times better than the best greenhouse technology!

The difference is in the energy content of algae as food.  In this case we're using the food energy for chlorella -- a widely consumed health food -- which is 410 food calories per 100g.  Chlorella just happened to have been the first algae species test-grown by Algasol, so these are verified production numbers.

Another thing to note here is that comparing tomatoes to algae isn't really fair to algae because algae possesses high concentrations of protein and omega-3 oils.

Now, one might object that people aren't going to eat algae directly whereas they will eat tomatoes directly, and this is true.  Not everyone is a healthfood nut and furthermore you don't want to make algae a primary component of your diet due to its high DNA (nucleic acid) content, which can cause gout.  Algae is best thought of as a foundation for agriculture:  It will feed the base of the agricultural food chain, just as do corn and soybeans now.  But if one looks at the energy losses in the food chain for, say, sockeye salmon -- a fish that eats algae and gets its "fish oil" directly from algae's oils -- the loss is about a factor of 2.  So that brings us down to a mere 3.5 to 1 advantage of Algae6 PBR over Dutch greenhouse production.  Ah... but now the shoe is on the other foot!  Everyone likes tomatoes, of course, but what about fresh sockeye salmon?  Moreover, with aquaponic technology coupled with aquaculture, the waste from from the fish is nutrient input to vegetable production.  So you can have your tomatoes and eat them with your salmon, too!

*The chemical formulas for the Calera process:

2NaCl+2H2O =>2NaOH + Cl2 + H2
CO2+2NaOH+CaCl2 => CaCO3+2NaCl+H2O

Combined with Calera's claimed reduction of energy usage by 60% with their “Alkalinity Based on Low Energy” (ABLE) process, yields the following energy/mass balance for CaCO3:

0.4*2*411.12kJ/mol;100.0869 g/mol?GJ/tonne
([{0.4 * 2} * {411.12 * (kilo*joule)}] / mole) * ([100.0869 * gramm] / mole)^-1 ? (giga*joule) / ton_metric
= 3.2861044 GJ/tonne

** Not that it is very important in this scenario but, yes, it does turn out that levelized algae oil costs for the Algae6 bring it into competition with crude oil — particularly when coupled with hydrothermal processes that have now been demonstrated.

Monday, August 19, 2013

Breakout Labs-Funded Prototype of Atmospheric Vortex Engine Nears Completion

The most newsworthy events are, for some reason, never reported by big news services.

For example, experiments that could change the world are imminent.

The Atmospheric Vortex Engine prototype funded by Breakout Labs is nearing completion.   The current state of construction is in this picture taken by the inventor's son, Eric Michaud:

Click the aforelinked "Wired" article for a description of the project.

Is this description "could change the world" hyperbolic?

Well, Thiel's vision for Breakout Labs rather demands that if you are worthy of funding, you will likely be accused by militant ignoramouses of being hyperbolic in your claims.

I don't know what Dr. Michaud actually proposed to Breakout Labs but for the answer as to whether I am being hyperbolic in my description of the potential importance of the soon-to-be-commenced experiments, here is what I suggested that Louis Michaud send to Breakout Labs as his proposal for his Atmosphic Vortex Engine:


Dear Dr. Michaud,

The Paypal co-founder, Peter Thiel, requests revolutionary proposals.  He is doing this through Breakout Labs.  The application page is at this link.  Both he and another Paypal founder, Elon Musk are partial to space development.  Since I am familiar with that interest, I've written my suggestion for two sections of a proposal to build your initial model.  This propsal also addresses Dr. Fiedler's concern voiced when, of his review of the CFD models of tornadoes, he said, "I found CFD codes are surprisingly untested for high Reynolds number vortices."


James Bowery, Research Analyst
Diogenes Institute

Atmospheric Vortex Engine
Develop sufficient understanding of vortices with high Reynolds numbers, such as tornadoes and hurricanes to allow investment in construction of full scale Atmospheric Vortex Engines.  This would be accomplished by building a model AVE capable of generating an atmospheric vortex approximately 100 meters high.  Measurements made on this vortex would then refine existing CFD models of vortices -- models which are surprisingly untested for high Reynolds numbers. 
The CFD model, validated for high Reynolds number vortices, would then be applied to the design of larger scale AVE’s to estimate their performance.  The economics full scale AVEs would then be evaluated and, if found profitable, provide start of a business plan.

10 Peta Watts renewable baseload electrical generation with no pollution.  The global deployment of AVEs turns the Earth into a heat engine using space for its heat sink.  The work of these heat engines is turned into electrical power by compact, high power turbines. 
Deploying AVEs in the tropical oceans would provide ocean settlements with copious quantities of fresh water rain and electrical power while controlling hurricanes.  These settlements would reduce population pressures while developing new options for voluntary experiments in the social sciences that may prove useful in existing polities as well as potential new space settlements.


An addendum:

I had neglected to mention that Peter Thiel is the primary underwriter for The Seasteading Institute; the potential of the AVE to facilitate oceanic settlements is uniquely positioned for his support.  Moreover, Peter Thiel is largely motivated by his radical libertarian views which include support of alternative lifestyles, such as his own gay orientation.  Therefore, the verbiage in my suggested "LONG TERM VISION STATEMENT" appealing to "voluntary experiments in the social sciences" supported by oceanic settlements, directly addresses his core values.

The connection between his core values and Seasteading is made by an article written by Peter Thiel for the CATO institute titled "The Education of a Libertarian".

Saturday, April 06, 2013

A Circuit Minimizing Multicore Shared Memory Latency

A massively multicore system on chip (SOC) can be built that executes current code without modification and with good utilization of the cores if the real-estate normally assigned to cache memories and maintaining cache coherence can be used for interleaved banks of shared memory  -- but only if mutual exclusion circuitry that resolves bank contention between cores does not impose too much latency or real estate overhead.

If you're still with me, you're the audience I want for the following disclosure of my invention of such a mutex circuit.

Its primary characteristics are:

1) Its real estate requirements are proportional to C*B where C is the number of cores and B s the number of banks.  In other words, a standard cell crossbar switch containing both shared memory elements and the mutex circuit is all that is needed in addition to the standard cell for the core -- regardless of the value of B and C.  Each core directly sees B crossbar standard cells that are aligned in a row seen directly by no other cores.  Each bank consists of C crossbar standard cells that are aligned in a column.

2) The latency introduced by mutual exclusion is log(C) where the base of the log is a large number -- much larger than 2.

3) Its power requirements are minimal.

Here's a brief disclosure:

Let's say you have 4 voltage sources, set to V1, V2, V3, and V4 with respect to ground feeding the anodes of respective diodes D1, D2, D3 and D4. What is the voltage across each of the diodes?

Consider this circuit.

In this circuit, each voltage source is producing a sine wave of different frequency.  Its transient analysis looks like:

The dark blue line represents the voltage on the wire that connects all the diodes together (at their cathodes).  The other colors represent the voltages of the respective voltage sources -- hence the voltage on the input to the diode (its anode).  Therefore the voltage cross each of the diodes is the distance from the dark blue line to their respective colored lines.

The thing to notice is the darker blue line is always just below, or on top of, the highest voltage at any point in time.  That means at almost any given point in time there is only one "winning" diode -- a positive voltage across it.  If a positive voltage sensor is placed across each diode, and that sensor outputs a binary 1 or 0, declaring if its sensed voltage is positive, we have a way excluding all but one of a number of "supplicants" from access to a shared resource such as a bank of memory.

So now, we place one of these voltage source, diode pairs in each crossbar switch and connect their cathodes in a line that reaches across cores to provide mutual exclusion for each memory bank.

That's where we get near constant-time, regardless of the number of cores.

We might want to use filtered noise voltage sources instead of sine waves, in order to be more random, but the principle is the same.

However, what happens in the "unlikely" event that two sensors report they see a positive voltage?  (I scare-quote "unlikely" because the more cores you have the more voltage sources you have hence the more likely there will be such a collision.)


Go ahead and settle for O(log(C)).  How?

A way to do this off the top of my head:  Lets say about 10% of the requests for a given bank will end up with voltages that are sensed as "winners".  That means 10% of the cores accessing that memory bank will have their sensor falsely report it has exclusive access to that interleaved bank.  90% of the core's crossbar sensors will block's its sensor from further contention but the remaining 10% continue to generate changing voltages.  At some point the 10% remaining contenders' voltages will diverge sufficiently to distinguish them.  Terminating this tournament depends on being able to detect when there is exactly one op amp for the interleaved bank reporting itself winner -- in the unlikely event it goes to 0 then the mutex is restarted with all requesting crossbar sensors active.  This results in a total mutex time that is, on average, log base 10 of the number of core's.

In this way, in System On Chip layouts -- where shared memory is on the same chip as the cores -- an exceedingly small latency for shared main-memory access can be achieved which obviates much of the real estate for cache hence cache and coherence logic per core.  This leaves more real estate for main shared memory.

One might object that the main memory would be of inadequate size for most practical applications however, keep in mind that the feature sizes now being achieved are below 20nm.  Moreover, if the cores are limited to 32 bit rather than 64 bit, the the number of banks and cores can be increased to the point that quite substantial applications can fit within the shared main memory constraints.

I leave it as an academic exercise how many cores and how much memory can be fit on a single chip -- and how long would be average main memory latency (including suspending execution while waiting for bank access), assuming all cores are executing threads.

Wednesday, March 06, 2013

The Delightful Cosmic Coincidence

The delightful "cosmic coincidence" between the Chelyabinsk meteor that produced widespread damage in Russia on February 15, 2013, just 16 hours before the closest pass to Earth of one of the more sizable asteroids known in history, has created a lot of "buzz" involving a lot of wild speculation despite authorities assuring us that the two events were independent.

It is rational to engage in otherwise "wild" speculation about possible explanations of a "coincidence" when two conditions are met:

1) The coincidence is between two events of possibly profound consequence.

2) The "odds" of the theories being batted around are at least as likely to be true as the "odds" of such a "coincidence".

There is a branch of mathematics taught at Ivy league business schools such as Harvard University called "decision theory" that does simple arithmetic to make investments of resources in exploring theories in just such a rational manner. The idea is that you have to take into account not only the probability of something, but its value in determining how much to invest in finding out more about it. A classic example is deciding how much to invest in mining assays of potential ore deposits before it makes no sense to pay attention to a potential mining site.

Regarding #1 (the value) we can certainly say that an asteroid impact on Earth results in a very large amount of damage ranging anywhere from a low yield nuclear bomb to the extinction of most major life forms, as has happened throughout the geologic history of Earth.

But what about #2: The odds of such a "coincidence"? How can we estimate those odds so that we can discount #1 rationally and not waste resources prospecting theories that are simply, themselves, too improbable?

Well, we have two statistically similar events, each with its own "probability" of occurring on average about once a century, give or take.

First of all, the correct treatment is as a Poisson process:


P is the probability
k = the number of times the rare event occurs
λ= the rate per unit time
t= the time interval over which the k rare events occur

  1. The Chelyabinsk meteor and the 2012 DA events are statistically similar events.
  2. These events occur roughly every 100 years.
  3. Our unit of time is 1 hour.
  4. A human lifetime is 80 years.

1 / ([100 * year] / [1 * hour])
= 0.0000011415525
= 0.00001826484
([e^-0.00001826484] * [0.00001826484^2]) / 2
= 1.6679914E-10

So, the odds of any particular 16 hour interval experiencing 2 of these rare events is about:

1/1.6679914E-10 1 / 1.6679914E-10 = 5.9952347E9
1 in 6 billion
So in an 80 year "generation" the odds of experiencing such a coincidence is:

1 - ([1 - 1.6679914E-10]^[{80 * year} / {16 * hour}])
= 0.0000073057752
1 / 0.0000073057752
= 136878.01

about 1 in a hundred thousand.

What a delightfully improbable coincidence to have been alive to witness an event of such quasi-eschatological impact! (Forgive my pun.)

Before I get into talking about the most plausible theory I have come up with to explain the otherwise delightful coincidence of February 15, 2013 between the close Earth flyby of an asteroid and the largest meteor entry to Earth's atmosphere in over a century -- both at mutually independent vectors -- I want to talk a little about another delightful coincidence:

While working at Science Applications International Corporoation's Roselle St. offices in Sorrento Valley of La Jolla, CA during the Reagan administration's "Star Wars" project, I would frequently receive mail addressed to a prior occupant of my office there: Peter Vajk. You might recall Peter Vajk as the author of "Doomsday Has Been Cancelled" in which he modified the Club of Rome's dynamical global model to incorporate non-terrestrial resources. In 1974, I wrote the first multiplayer 3D virtual reality (first person shooter) game called "spasim" in which I concocted a set of differential equations doing a mock up of the Club of Rome's model and the major theme of the game was the acquisition of nonterrestrial resources to keep the planet's population from going into revolt over terrestrial limits to growth. Vajk did his first work in this area in 1975. Oh but the delightful coincidence doesn't end there, because every day on my way to the industrial assembly area next door where I was managing the production of control software for an automated ordnance inspection system, I would walk past the Strategic Defense Initiative bays where, among other things, there were some rather impressive structures, presumably intended for orbital operation such as a very light-weight but powerful Van de Graaff generator intended to power who-knows-what.

I bring up this delightful coincidence because my early involvement with Gerard O'Neill's Space Studies Institute as Senior Associate 401 (right behind Ronald Reagan's membership number of 400) made me aware of an apparent disconnect between the DoE's solar power satellite studies and those of the non-terrestrial materials strategy popularized by O'Neill and Vajk: Not one of the studies of solar power satellites conducted by the major players such as the DoE even attempted a critical assessment of non-terrestrial materials studies. The citations were content-free dismissals. While we can chalk this up to a variety of bureaucratic characteristics, including conservatism or more simply bureaucratic stupidity, the events of February 15, 2013 lead me to suspect something more.

I had a bit of a hostile encounter with an old man who showed up at a space development conference in 1983 in San Francisco where I was representing Space Studies Institute and had designed their booth. Part of the booth was the book "The High Frontier" by Gerard O'Neill sitting next to the book "High Frontier" by Gen. Daniel Graham. Above the two books I had a sign that said "The Real Thing" and "Cheap Imitation" respectively. The old man walked up, his finger shaking in rage at the book by Gen. Daniel Graham and said, "This book could save this county!" I merely looked at him and told him that O'Neill's book had come out before Graham's and that Graham's didn't focus on the economics. The old man, still shaking, asked "Do you know who I am?" as he opened Graham's book and pointed to the name of the person who wrote the preface: "Robert Heinlein" at which point I merely looked him in the eye and said nothing with an expression saying "...and?..." He added, "There is no copyright on book title." I told him that Space Studies Institute had service marked ¨High Frontier" and that Graham had used it without permission. Heinlein then said simply, "I don't believe you." and walked off in a huff.

Heinlein, as you may recall from "The Moon is a Harsh Mistress", described a space-based kinetic energy weapon which, although of limited capacity, was of sufficient capacity to bluff a super power into submission.

Just one more thing before I get to the events of February 15, 2013:
A private company has now formed called "Planetary Resources" which is enjoying not only a lot of positive press, but substantial and prestigious financing and they are utilizing declassified spy satellite technology to prospect for Earth-approaching asteroids. As you are well aware, spy satellites technology has been far more advanced for a far longer time than has been openly acknowledged -- except perhaps by rumor -- and it is certainly the case that these technologies were being dramatically advanced and deployed during the Reagan administration.

So, now WHAT IF:

The limited military utility of tactical nuclear weapons was seen as mitigated by using kinetic energy weapons of similar yield?

The use of space-based kinetic energy weapons of high yield could be plausibly denied as "acts of god" only so long as the existence of such a weapons program was kept so secret that not even rumors of its existence leaked?

The potential value of such a plausibly-deniable, non-nuclear weapon system -- with potential high impact propaganda "Acts of God" on populations such as Islamics or American Christian Zionists -- was so great as to motivate massive military black project investment as early as the Reagan Administration if not the 70s?

The spy satellite technologies were, during this era, turned toward a comprehensive assay of low delta-v asteroids, including large meteoroids for use in such weapons?

The Department of Energy, being intimately involved in the execution of nuclear weapons policy, might have a conflict of interest in accurately reporting the potential of nonterrestrial materials in the construction of solar power satellites, as space-based kinetic energy weapons using nonterrestrial materials were being developed?

The near-earth flyby of the asteroid, now called 2012 DA14, was actually known well in advance of the amateurs -- indeed long enough in advance that a much smaller meteor could be vectored into a shallow-angle atmospheric entry over Russia to coincide with the asteroid flyby?

Perhaps without even any control over 2012 DA2012, the motive of concocting such a coincidence would be to telegraph a message to intelligence agencies that "You will notice we sent the asteroid's little brother in a controlled shallow-angle entry. Think what we could have done? Notice, also, how we've made your politicians who posit a US weapon system look like baffoons -- we still possess plausible deniability hiding behind an "act of God" propaganda." This has the Heinleinesque feature that it may be a bluff based on a very limited capacity to actually deliver such kinetic energy weapons from nonterrestrial resources -- a limit that would be very very difficult for adversaries to place reasonable error bars on.

The importance of the ABM and START treaties to this issue are that no one even conceived of limiting kinetic energy weapons as replacements for nuclear warheads.

To commemorate the signing of the START I treaty -- which may well have given impetus to find non-nuclear energetic weapons of mass destruction -- on July 31, 1991, the House Subcommittee on Space held hearings on space commercialization. During those hearings I gave testimony.on legislation my coalition had promoted to privatize space launch systems. Then I became Vice President for Public Affairs at E'Prime Aerospace, which had been given license by the Bush Administration to take control of the Peace Keeper Missle production lines for the purpose of turning them to commercial launch services by adapting the MIRV upper stage with a geostationary orbital system.

The dramatic reduction of MIRVs in the strategic arsenal, on the very day that I testified, freed up a lot of resources.

Finally, I'd point out that John Pike, as recently as 2004, was quoted in Popular Science as saying that a space-based kinetic energy kill weapon called "God's Rod" was unfeasible because of the high launch costs from earth. John Pike, as I recall from the Reagan Administration era, was the same guy who was referred to as "the expert" by popular press accounts of the unfeasibility of solar power satellites due to launch costs.

If, as I posit, there already existed a space-based kinetic energy weapon utilizing nonterrestrial resources at the time John Pike wrote his dismissal, why would anyone be interested in developing a weapon like "God's Rod"? Well, perhaps they aren't really interested in it.... perhaps it is just a diversion/cover On the other hand, there is a very good reason for wanting a weapon like "God's Rod" over a kinetic energy weapon that requires years of set up time for targeting:

Tactical, as opposed to strategic, utility.

So, to wrap up this second part of the story we are now in a position to estimate the probability of this theory and whether it is as least as probable as being alive during a 1 in a hundred thousand 80 year lifespan.

It boils down to this: The least plausible aspect of this theory (the weakest link in the inferential chain) is that a government possessing ample means, motive and opportunity, could actually pull off a black project spanning 2 decades with funding of on the order of a few tens of billions of dollars (at most). Does this stand a chance of at least 1 in a hundred thousand?

PS: There is also the delightful coincidence of my walking into Memex Corp. for the first time and having the 3-way exchange between Gary Olsen, Keith Henson and myself of "What are YOU doing here???" as we had all known each other for 15 years as being leaders of the nonterrestrial materials use advocacy.

Saturday, December 22, 2012

Sortocracy's Compassion

Sortocracy:  Sorting proponents of social theories into governments that test them.

Why is this compassionate?

1) It protects people from the political imposition on them of bad social theories.

2) It teaches people with bad social theories the consequences of those theories.

3) It demonstrates the efficacy of good social theories so that progress in the social sciences is practical.

4) It reduces a major cause of war:  the continuation of politics by other means.