Rocket Doc Notes for Week of May 23, 2021
My take on future life on this planet – Part II
Last week I discussed what is causing the current West coast Drought (La Nina Ocean Cooling) and the impact that self-driving cars and trucks are going to have on carbon emissions. This week the topics are the world’s declining fertility rate, the possibilities of using ammonia (NH3) to eliminate most fossil fuels, and the latest news on the space front.
Falling Human Fertility – The number of babies each woman needs to have for the country's population to hold steady is 2.1 births per woman on average (2.1 makes up for infertile women and babies who don’t live to adulthood). By 2019, the average number of births per woman in the United States had fallen to 1.71, and last week the CDC announced that the number dropped to 1.64 in 2020. This is good news! Falling fertility rates mean nearly every country could have shrinking populations by the end of the century, ending the main threat of starvation in the Limits to Growth scenario we have been discussing.
In fact, 23 nations including Spain and Japan are expected to see their populations halve by 2100, and many countries will also age dramatically, with as many people turning 80 as there are being born. These demographic changes will cause many headaches to local governments who now have fewer workers to support more retirees, but the increasing standard of living associated with these countries means that balancing taxes with retirement funding should be workable. Let the politicians earn their salaries for a change. The Global Fertility Rate and projection is shown in figure 1 below.
Figure 1 – Global Fertility Rate (livebirths per woman)
Based on this projection, researchers expect the number of people on the planet to peak at 9.7 billion around 2064, before falling to 8.8 billion by the end of the century. This assumes Africa can solve its current high fertility rate (~ 5 live births per woman), but if this holds true humankind has essentially solved the Limits to Growth disaster scenario.
Ammonia as an energy storage solution – A few weeks back I introduced you to the possibility of generating ammonia at renewable energy generation sites to store the energy available periodically because of favorable generating conditions, but that is more than local power requirements. Normally this power is purposely not generated by tilting the solar panels and/or “feathering” the windmill blades. If we could expensively store this bonus energy on-site, we could operate our renewable powerplants at maximum efficiency and eliminate a considerable amount of backup power generation (much of which is fossil-fueled). This is news because it appears there has been a breakthrough with respect to a simplified version of the hundred-year-old Haber-Bosch Ammonia generation process. The classic Haber-Bosch process is shown schematically in figure 2 below. In the classic process methane, water, and air are combined in a series of catalyst reactors and scrubbers to produce pure nitrogen and hydrogen gases which are then compressed to about 300 bar and heated to 450 degrees Celsius in the presence of a metallic catalyst which converts about 15% of the gas to ammonia. The remaining 85% of the nitrogen and hydrogen are recycled for another pass through the catalyst bed.
Figure 2 – Classic Haber-Bosch Ammonia Production Process
The most recent efficiency numbers for a large modern Haber-Bosch plant are 26 GJ/mT of Ammonia (772.3 kW-hr/mT NH3), or 0.433 kW-hr/Liter of liquid NH3.
The new player in Ammonia is the Green NH3 Company which was started by Roger Gordon, a Canadian inventor and businessman. Green NH3 merged with EEstor Company in Canada in August 2020 and now trades under the name Fuel Positive Corporation (ticker symbol NHHHF). Roger Gordon’s original refrigerator-sized Ammonia generator underwent a redesign at the Ontario’s University of Technology’s Gaseous Fuels Laboratory and the company is now offering shipping container-sized units suitable for ammonia generation and storage at windmill or solar panel sites. The company is claiming their new process is 30% more efficient than the original Haber-Bosch process, but there is no qualifying data. They are presently conducting a rollout of a full-sized demonstration and test unit. A picture of their proposed container-sized demonstration unit is shown in figure 3 below.
Figure 3 – Fuel Positive Ammonia Generation Demonstration Plant in Shipping Container
If their demonstration unit works as advertised and if their efficiencies are as advertised, they could become a major factor in the struggle to eliminate fossil fuels. The logic for this is as follows. It is not economic to use batteries to store renewable energy to make up for the periods of off-nominal power generation. Those periods can last for days, and the batteries required would be ridiculously expensive. There have been efforts like pumped-water and pressurized-air storage but those have also been uneconomical except for certain favorable sites. The best candidates are generation of energy storage gases, particularly hydrogen and ammonia. Unfortunately, hydrogen is expensive, energy-wise to generate and store, which limits its use even though it is an excellent fuel for combustion engines. Ammonia has not been a reasonable candidate until Fuel Positive entered the scene because all our ammonia was made from methane, a fossil fuel, using the Haber-Bosch process. With the Fuel Positive process Ammonia is made from air and water using “free” electricity available from renewable energy powerplants. This is a very persuasive argument.
The basic idea is that every windmill or solar panel farm would have its Fuel Positive shipping container to generate liquid ammonia whenever the power output exceeded that required by the distribution network. Then when night fell, or the wind died the ammonia would power Solid Oxide fuel cells or maybe gas turbines to generate the nominal power output to keep the distribution network from having to rely on fossil-fueled backup powerplants. This would enhance the standalone capability and distribution of electrical power increasing reliability.
Ammonia could also function as an energy source for transportation and provide an alternative to battery-powered cars and trucks. This is possible because liquid ammonia can be stored as a liquid at 10 bars (atmospheres) much like propane and if consumed in a Solid Oxide fuel cell would give approximately the same miles per gallon as a gasoline car with the same refuel times and characteristics. I haven’t run the numbers, but I suspect a 100 kW Solid Oxide fuel cell should require far fewer critical materials than a 100-kW-hr battery pack and probably be cheaper. The idea would be to replace short-range cars and trucks with Electric Vehicles (EVs) and replace the long-haul cars and trucks with ammonia-fueled vehicles that carry enough fuel for extended range, and which can be refueled in seconds with a pressurized hose connection. In both cases there are no carbons emitted. This is a developing story, and I will continue to track it. Again, technology is showing ways to beat global warming.
Latest Space News - It’s certainly been an eventful few weeks for America’s space program with the recent return of astronauts from the International Space Station and confirmation of NASA Administrator Bill Nelson. However, readers of this blog know that there’s controversy swirling around NASA these days after the agency awarded the Artemis Human Landing Systems (HLS) contract to a single contractor, SpaceX, instead of NASA’s typical standard of awarding to multiple contractors. This has offended many of the lobbyists in D.C. and much of the media are arguing that by breaking with precedent and simply awarding the contract to SpaceX, NASA is proving that it is not serious about returning to the moon in 2024. This argument overlooks the problem that Congress didn’t provide sufficient funding to allow NASA to make meaningful multiple awards. With the funding provided NASA could either make one HLS award or make multiple awards and postpone the lunar landing by five or six years and possibly let the Chinese claim key locations on the moon.
The award to a single provider is in opposition to the agency’s long-stated strategy for the Artemis program: “to work with multiple companies so NASA avoid the costly delays and suspensions that have plagued the ambitious programs of the agency’s past. In bucking the process that has shown so much promise, NASA has elevated the risk of its most important program, which is tasked with returning astronauts back to the moon”. True, but “no Bucks, no Buck Rodgers” trumps the risk paradigm. If the swamp dwellers in Washington D. C. want multiple awards on the HLS Program to reduce risk let them find the extra funds (at least $6 B).
Plus, it has proven to be very risky to bet against SpaceX innovative capabilities. They have proven the naysayers wrong on multiple occasions and given the current state of their Starship Program I don’t view their approach to be as risky as the Blue Origin approach and certainly much less risky than the Dynetics approach. Risk level is often in the eye of the beholder, and I have worked on multiple lunar lander contracts for NASA over the years. I would view the SpaceX approach as novel but based on hardware that will exist well before 2024. They have offered to modify existing hardware to allow NASA not only the opportunity to land the first woman on the moon, but to actually put bases on the moon in the 2024 timeframe and do it for the limited funds available to NASA. That is a huge win for NASA and for our country.
Thanks for Reading,