H2 & NH3 Combustion Technologies

Variable renewable energy.

Meaning, the Sun doesn't come out at night. We can have sunny, cloudy, or rainy days.

In addition, wind can blow and stop.

Thus, Renewable energy needs backup.

1. Natural-gas-fired power generation can back up renewables.
2. If we want Renewable-Energy-100% (RE100%), renewables must be equipped with backup measures.

CASE 1: U.S.A.

According to "Green Ammonia for Fertilizer, Fuel, and Energy Storage @ Minnesota Public Utilities Commission Planning Meeting,"

CASE 2: Japan

(1) Panasonic also has started RE100% Project: solar panels, 570 kW; Li-ion batteries, 1.1 MWh; PEFC, 500 kW.

Hydrogen is not green for now, however, it would become green in future, according to Panasonic. (i) 570-kW solar panels can generate 4.56 MWh/d when it is sunny, and 0.00 MWh/d when it is rainy. (ii) 500-kW PEFC can generate MAX 12.00 MWh/d. (iii) 1.1-MWh batteries can cover 1.93 h for solar.

(2) By the way, some are criticizing why METI is trying to suppress renewables within 50-60%; however, as described later,

1. Si solar panel: ¥240,000/kW-¥350,000/kW without backup cost; occupancy ratio = 12% (thus, the real initial cost is ¥2,000,000/kW-¥2,916,667/kW); 20 years of durability (preferably, 40 years).
2. Wind turbine: ¥3,000,000,000/10 MW (¥300,000/kW) plus the running cost (¥6,000/kW) without backup cost; occupancy ratio can be 40-60% (thus, the real initial cost is about ¥600,000/kW); 20 years of durability (preferably, 40 years).
3. Gas power plant: ¥1,000,000,000,000/1 GW (¥1,000/kW) plus the fuel cost (¥10/kWh, thus, it can be ¥70,080,000,000/yr -- this is the reason why I say that renewables are not bad); occupancy ratio = 80%, if it does not have to back up renewables (thus, the real initial cost is about ¥1,250/kW); 60 years of durability.
4. If the power mix becomes fossil fuel : H2/NH3 fuel : renewables = 40 : 10 : 50 (*1), we would need 100% fossil fuel plus H2/NH3 fuel (50% is for renewables backup). The fuel cost can be decreased, e.g., by (30/80)=37.5%, corresponding to ¥2,747,500,000,000/yr in Japan -- this is the reason why I say that renewables are not bad.
5. However, if 50% of 260,000,000 kW, i.e., 130,000,000 kW is replaced to renewables, it can cost ¥31,200,000,000,000-¥45,500,000,000,000 for solar or ¥39,000,000,000,000 for wind. It can take 11.3-16.6 yr for solar and 14.2 yr for wind in order to be compensated by the fuel-cost decrease. It should be noted that the budget of Japan is ¥107,000,000,000,000/yr, and the GDP of Japan is ¥540,000,000,000,000/yr.
6. Then, renewable business should consider the backup, and the business, e.g., Softbank, should procure green power themselves (like Tesla, Microsoft, Apple etc.), not asking the help from the country (actually, people). In reality, the country (actually, people) helps them to some extent, though.

• *1: Japan is going to generate 50-60% of electric power by renewables, and 40% by fire power and nuclear power in 2050.

(3) Some are criticizing about the green hydrogen cost that is 900% compared to nuclear power.

1. That is currently true.
2. Even so, renewables cannot become full-fledged without producing green hydrogen and supplying electricity by using the produced green hydrogen via fuel cells, hydrogen turbines etc. Otherwise, fossil-fuel-based fire power must back up renewables. Note that CO2 emission must be decreased in total, thus, hydrogen and/or ammonia will be required, instead of coal and gas.

By the way, brown hydrogen is, actually, for national energy security. Australian young coal can cover 240 years for Japan. Then, the opponents must be categorized as terrorists.

1. As described in Electrochemical Impedance Analysis for Fuel Cell (& economy a bit -- actually, a lot). | LinkedIn, China, which is a coal producing country, is producing hydrogen as a syngas from coal at the comparable cost as natural gas. Hydrogen from young coal is currently more expensive than that; however, we can expect the cost would be decreased to the comparable cost as coal-based syngas.

Renewables are not cheap:

In descending order of renewables ratio,

1. The average power price for households and small businesses in Germany stood at 30.43 cents per kilowatt hour (ct/kWh) in 2019, according to the economy and energy ministry (BMWi).
2. Japan, September 2020: The price of electricity is 0.265 U.S. Dollar per kWh for households and 0.201 U.S. Dollar for businesses which includes all components of the electricity bill such as the cost of power, distribution and taxes.
3. The average electricity rate is 13.19 cents per kilowatt hour (kWh). The average price a residential customer in the United States pays for electricity is 13.31 cents per kWh.

Even so, renewables and H2/NH3 are not so bad, when thinking about fossil fuels consumption so far:

1. LNG: Japan imported 80.55 M ton of LNG in 2018, corresponding to 1,010×80,000-ton tankers per year (2.8 per day). 64% was used for power generation, 36% for city gas. 55.6% of city gas is used for industry, 24.9% for home use, 11.4% for commerce, and 8.1% for others. It should be noted that LNG is liquified and stored at 108 K (-165 oC), thus, boil-off is unavoidable -- it means the long-term stockpiling is difficult, then, LNG reserve in Japan is just for 20-day domestic consumption.
2. COAL: Japan imported 113.694 M ton of coal in 2018, corresponding to 1,264×90,000-ton ships per year (3.5 per day). 44% was used for power generation, 33% for steal industry, 6% for cement industry etc. Coal reserve in Japan is about for 30-day domestic consumption.
3. OIL: Japan imported 61.97 GL of crude oil in 2018. The density of crude oil is 0.9kg/L, thus, 620×10,000-ton tankers per year (1.7 per day) transported the oil. 41.8 was used in the transportation sector, 20.5% for chemical industry, 11.9% for power generation, and the rest for heat generation. Crude oil reserve in Japan is for 208-day domestic consumption.
4. LPG: Japan imported 10.64 M ton of LPG in 2018, corresponding to 213×50,000-ton tankers per year (0.6 per day). 52% was used for home use, 18.9% for industry, 14% for chemical industry, 9.6% for city gas, 4.5% for taxies etc., and 1.0% for power generation. LPG reserve in Japan is for 105-day domestic consumption.

Then, we would need to decrease both coal and gas consumptions.

Regardless of a negative campaign against coal (a positive campaign for gas),

1. How Autocrats From Russia and Kazakhstan Use London to Strike Foes Worldwide.
2. UK seeks to drill more oil and gas from North Sea.
3. Climategate: the ground zero was London.

we have to work on "energy self-sufficiency" one after another, in addition to "intelligence self-efficiency" and "national defense self-efficiency (it is a very strange definition)."

Previously, Electrochemical Impedance Analysis for Fuel Cell (& economy a bit -- actually, a lot).

Previously, Electric-Power Generation, Power Consumption, and Thermal Control (mainly economy, thermodynamics a bit.).

I. Main Body

Japan is heading to, so-called, Hydrogen Society (H2 Society), which actually includes the use of ammonia (NH3).

Hydrogen and ammonia are preferably produced via renewables:

1. The world biggest H2 production based on renewables @ FH2R, Fukushima.
2. Japan is going to produce green ammonia in Akita prefecture.

Such green hydrogen and ammonia still cost a lot when produced in Japan, thus, green fuel would be mainly imported until the low-cost, made-in-Japan green fuel becomes available.

The latest news

Green Ammonia

1. Japan is going to produce green ammonia in Laos.
2. Japan is going to produce green ammonia in Malaysia.
3. A Japanese company is going to construct green ammonia production plant in Middle East and Australia.
4. Yara and JERA sign green ammonia MoU.

Blue Ammonia/Hydrogen

1. Japan is going to import blue ammonia from Saudi Arabia. The primary reason is the cost -- currently, the lowest. The secondary reason is, ammonia is much easier to transport/stock than LNG. Saudi Arabia can enjoy another merit -- CO2 is used to increase the oil production.
2. A blue hydrogen plant in Australia, which corresponds to 240-year power production for Japan, has been launched. The primary reason is, the young coal cannot be transported as it is. The secondary reason is the quantity. The third reason is the location. Australia can enjoy another merit -- it gets one more resource to sell.

Hydrogen-Fired Power Plant

1. Steel makers of Japan, such as Nippon Steel which has the 6th biggest power generation capacity in Japan, have been generating electricity via hydrogen-mixed fire power stations, including 1-GW class.
2. There are some smaller hydrogen-mixed fire power stations such as a 1-MW class in Kobe. According to NEDO, "The water injection method previously used for purposes of mitigating NOx emissions induces the reduction of electrical efficiency, because of evaporation of water spray in the hot combustion gas. In comparison, use of the dry low NOx combustion method improves the electrical efficiency and NOx emission values. However, in case of hydrogen, high combustion speeds characteristics causes the problem of flashback. To realize both stable hydrogen combustion and low NOx emissions is an important issue. To address this issue, Kawasaki applied the micro-mix combustion technology, which features ultra-small hydrogen-fueled flames, to the industrial gas turbine combustor, and successfully developed the world's first 100% hydrogen-fueled dry low NOx gas turbine, during the verification tests started in May 2020 on Kobe's Port Island. The cogeneration system combining this hydrogen-fueled gas turbine and a heat recovery steam generator is capable of supplying approximately 1,100 kW of electricity and approximately 2,800 kW of thermal energy in the forms of steam or hot water to public facilities in the area."

2-MW Micro-mix combustor. (Kawasaki Heavy Industries Ltd.) -- It says that the diameter of the hydrogen nozzles is around 0.5 mm, thus, it can work as the flame arrestor. For hydrogen the diameter less than or equal to 0.64 mm is required.

At high temperatures, hydrogen can easily react with the metal-surface oxide film (high-temperature tolerant metals are usually nickel-based alloys): the repetitive oxidation (due to oxygen) and reduction (due to hydrogen) can make metal parts thinner and thinner. The high-temperature tolerant turbine's inner surface is usually protected by air flow.

Ammonia-Fired Power Plant

1. NH3-combustion power generation is also under research. It should be noted that NH3 is synthesized from hydrogen and nitrogen distilled from the liquified air via Haber-Bosch process. Ammonia is much easier to be transported/stockpiled than hydrogen (Ammonia is liquefied at 1 MPa and 25 oC), thus, it would be implemented relatively early.
2. The top is the coal-and-ammonia-fired gas turbine. The bottom is the 550-MW 100%-ammonia-fired gas turbine, which the exhaust heat is used for partial ammonia decomposition to hydrogen and nitrogen.

• According to Kobayashi et al., the low NOx ammonia gas turbine combustor has been developed. It is using two-stage combustion. The NOx emission was above 1,000 ppm. More recent data exhibits the NOx emission of 337 ppm. In order to decrease the NOx emission, the air dilution in the primary combustion zone was avoided, and the fuel-air mixing was enhanced by the use of inclined fuel injection. Note that the additional NOx emission decrease technologies, which have been developed for fossil-fuel fire power plant, is also available.

• Ammonia is produced via Haber–Bosch process that used Fe catalyst, then, now uses Ru catalyst. At the Fe and Ru surfaces, nitrogen relatively easily adsorbs.
• In 2012, Ru particles supported by 12CaO-7Al2O3-based electride was reported to exhibit a better performance than Al2O3, CeO2, MgO etc. because of the H^- and electron donor, reduced 12Cao-7Al2O3. Thus, K2O etc. was not used. / Ammonia synthesis using a stable electride as an electron donor and reversible hydrogen store.

• In 2019, BaCeO3 in which oxygen is partially replaced to nitrogen and hydride ion was reported to be able to produce ammonia even without metal particles catalyst. With Co, Fe particles, it exhibits better performance. / Low-Temperature Synthesis of Perovskite Oxynitride-Hydrides as Ammonia Synthesis Catalysts

• In 2020, Ni supported by LaN exhibited better performance. / Contribution of Nitrogen Vacancies to Ammonia Synthesis over Metal Nitride Catalysts

In 2020, NH3 was produced at 50 oC by using Ru/CaFH catalyst.

Infrastructure

Hydrogen needs to be liquified at 20 K (-253 oC).

(i) At temperatures higher than the Joule-Thomson inverse temperature (204K, -69℃), the temperature of hydrogen must be decreased by heat exchange with, e.g., liquid nitrogen.

(ii) During the heat exchange, the nuclear spin of hydrogen must be changed. At normal temperatures, the ratio of ortho-hydrogen (the spin is parallel) and para-hydrogen (the spin is anti-parallel) is 3:1 (it is called normal hydrogen). When liquified, the ratio changes into 1:9. Since the para-hydrogen is thermodynamically more stable than ortho-hydrogen, the heat is emitted via nuclear-spin change, then liquified hydrogen is boiled off, e.g., 60%.

• "Ortho-para transition would take place via molecule-molecule collision or via molecule-wall collision during the cooling, then, resulting in boil-off. I order to cool hydrogen in an efficient manner, ortho-H2 must be converted to para-H2 via Fe(OH)2 or Cr2O3."

(iii) When reaching the temperatures lower than the Joule-Thomson inverse temperature, hydrogen is expanded adiabatically, then, the temperature can now be decreased more in the same manner as other types of gas.

1. At temperatures lower than the inverse temperature, the thermodynamic gain via intermolecular attractive force is lost by adiabatic expansion (then, the potential energy becomes higher). Since the total energy must be kept constant (it is the adiabatic expansion), the molecular kinetic energy is decreased. It means the temperature decreases.
2. Normal temperatures are above the inverse temperature of hydrogen, thus, its potential energy is limited by intermolecular repulsive force rather than intermolecular attractive force. Then, the adiabatic expansion results in the potential energy decrease. As already mentioned, the total energy must be kept constant, then, the molecular kinetic energy is increased (the temperature increased).
3. Temperature, T, is thermodynamically related to molecular kinetic energy, Ek: monoatomic molecule, Ek = (1/2)mv^2 = (3/2)kT (One-dimensionally, Ek = (1/2)kT, totaling (3/2)kT three-dimensionally.); diatomic molecule, Ek = (5/2)kT (In addition to three-dimensional translational energy, (3/2)kT, the molecular rotations along the two axes excluding the molecular axis have 2 * (1/2)kT. A molecular vibration mode has kT; however, the energy gap is relatively large, thus, the quantum mechanical effect must be considered. Then, the contribution to the temperature becomes zero. ).
4. Hydrogen must be liquified and stored at 20 K (-253 oC). Hydrogen is stored in the double-walled tank: (i) vacuum between the wall, and (ii) laminating aluminum foils for infrared reflection and heat insulators for achieving the low heat transfer is required.

It has been reported that SUS316L (18Cr-12Ni-2.5Mo-low carbon) is low-temperature tolerant.

1. SUS316L is also chosen for fuel cells because of its hydrogen-embrittlement tolerance: its high-density fcc structure is reportedly the reason to suppress hydrogen penetration. TiC-, TiN-, Al2O3-, BN-, or diamond-like-carbon-coating is reportedly also effective to suppress hydrogen penetration.
2. Type 3 high-pressure tanks use aluminum-alloy, A6061-T6. For hydrogen stations, the lower cost of Cr-Mo steel might be prioritized. Note that the melting point of aluminum is 600 oC.

When polymer- or elastmer-based O-ring is required, the composite of ethylene-vinyl alcohol copolymer and acid-anhydride-modified PTFE has been recommended: it exhibits the relatively high blister-destruction tolerance because of matrix-domain hydrogen bond that can suppress hydrogen penetration at high pressures into amorphous parts that results in the expansion at low pressures. Poly-(vinyl alcohol) (PVA) suppresses hydrogen penetration because of its intra- and inter-hydrogen bonds, but it cannot be microscopically mixed with other polymers without modifying by ethylene.

1. Type 4 high-pressure tanks reportedly use polyamide liner (nylon-6 liner) that also suppresses hydrogen penetration.

Things to be careful of when using hydrogen are ①very leaky, ②the minimum ignition energy is only 0.02 mJ (0.28 mJ for methane), thus, the electrostatic discharge from a human body or rust can ignite it. It has been reported that high-pressure hydrogen leak can result in the sudden ignition due to the friction with the dust in the air.

Industrial H2 shift

1. Mitsubishi Heavy to build biggest zero-carbon steel plant.

• Industrial CO2-emission decrease: Japanese cement producer Taiheiyo Cement Corp will implement technology for CO2 capture from the flue gas of rotary cement kilns in the first, 10tpd demonstration plant in Japan. For this purpose, Taiheiyo Cement has selected the technology for CO2 chemical absorption supplied by UK-based Carbon Clean, which has been awarded by Marubeni Protechs Corp (Marubeni Protechs) in Japan. This technology will be installed at Taiheiyo Cement's plant in Kumagaya City, Saitama, and demonstration tests are expected to begin in September 2021. 

Decoupling for Renewables

Renewables, such as solar and wind, are intermittent, thus, need flexible backup. Currently, fire power is used to backup renewables. In the near future, fuels for fire power need be replaced to H2 and NH3.

H2 production via water electrolysis from renewables (= so-called green H2) can solve this dilemma. The challenging issue is the cost.

It has been expected that green H2 cost would become lower when using not only surplus power but also baseload power:

1. The current target is ¥26.49/Nm^3 -- CH4-equivalent cost is ¥20/Nm^3.

NH3 can generate 12.7 MJ/L, which is 1.52 times higher than that of H2, 8.4 MJ/L.

1. Then, NH3 at ¥40+x/Nm^3 is expected -- ¥30+x/Nm^3 is preferable.

It has been reported that relatively small-capacity battery-banks (perhaps, as the decoupling measure for several to several dozens minutes) would be useful in order to decrease the green H2 production cost:

1. As already reported, Furukawa, the 3rd biggest lead battery manufacture in Japan, has announced that its bipolar lead battery would be launched. The cost would be 50% of the conventional lithium-ion batteries.
2. Conventional lead batteries reuse is under research. The cost would be 10% of the conventional lithium-ion batteries.
3. Feed-in-Tariff is just for lowering the entry barriers for renewables (particularly for small capacity), then, renewables are required to be operated under Feed-in-Premium. This would result in the need for the investment in the decoupling for renewables businesses.

by T. H.

Appendices

Any renewables are fine, only if renewables can provide power at a comparable cost with the conventional power plant, including the backup cost.

1. Si solar panel: ¥240,000/kW-¥350,000/kW without backup cost; occupancy ratio = 12% (thus, the real initial cost is ¥2,000,000/kW-¥2,916,667/kW); 20 years of durability (preferably, 40 years -- some have already reached.). Perovskite has reached 20 years, although the energy conversion efficiency is still low, 12%. Then, it would serve to make up for Si. Note that Sekisui is aiming for the commercialization in 2025 (they say that the energy conversion efficiency has reached 14.3%).
2. Wind turbine: ¥3,000,000,000/10 MW (¥300,000/kW) plus the running cost (¥6,000/kW) without backup cost; occupancy ratio can be 40-60% (thus, the real initial cost is about ¥600,000/kW); 20 years of durability (preferably, 40 years).
3. Gas power plant: ¥1,000,000,000,000/1 GW (¥1,000/kW) plus the fuel cost (¥10/kWh, thus, it can be ¥70,080,000,000/yr -- this is the reason why I say that renewables are not bad); occupancy ratio = 80% if it does not have to back up renewables (thus, the real initial cost is about ¥1,250/kW); 60 years of durability.
4. If the power mix becomes fossil fuel : H2/NH3 fuel : renewables = 40 : 10 : 50, we would need 90% fossil fuel plus H2/NH3 fuel (50% is for renewables backup), totaling 150%. The fuel cost can be decreased, e.g., by (30/80)=37.5%, corresponding to ¥2,747,500,000,000/yr in Japan -- this is the reason why I say that renewables are not bad.
5. However, if 50% of 260,000,000 kW, i.e., 130,000,000 kW is replaced to renewables, it can cost ¥31,200,000,000,000-¥45,500,000,000,000 for solar or ¥39,000,000,000,000 for wind. It can take 11.3-16.6 yr for solar and 14.2 yr for wind in order to be compensated by the fuel-cost decrease. It should be noted that the budget of Japan is ¥107,000,000,000,000/yr, and the GDP of Japan is ¥540,000,000,000,000/yr.
6. Then, renewable business should consider the backup, and the business, e.g., Softbank, should procure green power themselves (like Tesla, Microsoft, Apple etc.), not asking the help from the country (actually, people). In reality, the country (actually, people) helps them to some extent, though.

[1] Although the challenges for scale-up still lie, there are some less energy-consuming ammonia production technologies:

According to "Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon By Robert F. Service Jul. 12, 2018," reverse fuel cells can use renewable power to make ammonia from air and water, a far more environmentally friendly technique than the industrial Haber-Bosch process.

Osaka Gas USA has invested in Starfire: April 9, 2021.

According to "Molybdenum-catalysed ammonia production with samarium diiodide and alcohols or water," the combination of samarium(II) diiodide (SmI2) with alcohols or water enables the fixation of nitrogen to be catalysed by molybdenum complexes under ambient conditions.

These technologies might become the solution not only for green NH3 synthesis but also for CO2 recycle. CO2 recycle can be used for synthesizing methane, propane, butane etc.

[2] Climate Matter

Although (1) the invention of the short-centering has become a controversial topic (in addition, the dishonest behavior has been criticized [1], [2]),

(2) and the CO2 concentration has been increased 800±200 years later than the temperature increase,

(3) the sea-level is basically rising this 36,000,000 years (well, it is not increasing this 3,600 years.). Thus, we are living in the era of the temperature increase and the sea-level increase.

In addition, the temperature-increase in the Greenland was obeserved during 1920-1930, then, decreased, and then, increased again from 1990:

グリーンランドのみならず北極圏の氷河の減少は確認されている。いずれはズルっと海中に落ちるかもしれない。

(cf.) According to Wikipedia, "The Little Ice Age was a period from about 1550 to 1850 when certain regions experienced relatively cooler temperatures compared to the time before and after. Subsequently, until about 1940, glaciers around the world retreated as the climate warmed substantially. Glacial retreat slowed and even reversed temporarily, in many cases, between 1950 and 1980 as global temperatures cooled slightly.[1] Since 1980, climate change has led to glacier retreat becoming increasingly rapid and ubiquitous, so much so that some glaciers have disappeared altogether, and the existence of many of the remaining glaciers is threatened. In locations such as the Andes and Himalayas, the demise of glaciers has the potential to affect water supplies. The retreat of mountain glaciers, notably in western North America, Asia, the Alps and tropical and subtropical regions of South America, Africa and Indonesia, provide evidence for the rise in global temperatures since the late 19th century. The acceleration of the rate of retreat since 1995 of key outlet glaciers of the Greenland and West Antarctic ice sheets may foreshadow a rise in sea level, which would affect coastal regions." Note that the reference period 1960-1990, overlaps the period 1950-1980, when Glacial retreat slowed and even reversed temporarily as global temperatures cooled slightly.

Furthermore, the order inversin between the temperature-increase and the CO2-concentration increase might have been observed around 1988, or it may just a piece of noise:

Regardless of a sociological opinion (I cannot see a piece of science from this opinion), these two have been the only scientific data that makes me think about the global warming.

Regardless of the ignorable fear (Prof. Takeda has pointed out that the fear is not based on science) and the Greenpeace, we need to research the relation between the temperature and the water content by using CO2 concentration as a parameter, instead of the statistic positive correlation between the temperature and the CO2 concentration.

Possible Global Warming Factor 1: the Greenhouse effect

1. The emissivity of thermal insulator is quite high, e.g., 0.8-0.9 (80-90% of the black body). Polyvinyl chloride has a high emissivity as well: it is transparent to visible light from the Sun, thus, the soil in the greenhouse is warmed during the daytime even in winter. During the night, the soil emits the infrared (e.g., 0.75-25 um). However, the emissivity of polyvinyl chloride is high, thus absorbs and emits back the infrared to the soil. In conclusion, the soil in the greenhouse can be kept warm to some extent. This is the Greenhouse Effect (1).
2. Water (H2O), methane (CH4), and carbon dioxide (CO2), are transparent to visible light from the Sun, thus, the Earth is warmed during the daytime even in winter. During the night, the Earth emits infrared. However, H2O, CH4, and CO2 adsorbs and emits back the infrared to the Earth because of the antisymmetry of H2O (its molecular (bond) vibrations are antisymmetric) and of antisymmetric molecular (bond) vibrations of symmetric CH4 and CO2. This is the Greenhouse Effect (2).

• By the way, the Greenhouse Effect (2) is mainly due to H2O, e.g., 90%. The water content in the atmosphere is e.g., 3% in summer. It becomes 0.2% in winter. This is the reason why winter morning can become very cold. CO2 concentration is increasing: now, 415 ppm.
• Note that the more infrared is radiated back to the surface of the Earth when the temperature is increased because of the H2O(g) increase and the CO2(g) increase. Both can be forced out of the sea water -- this is categorized as the positive feedback (↑). Even so, the more infrared is radiated toward the space when the temperature is increased -- this is categorized as the negative feedback (↓).

Possible Global Warming Factor 2: the Loss of the Ice Albedo

1. The ocean albedo is about 0.06, while the sea ice albedo is 0.6±0.1. Thus, the Arctic Sea is losing its infrared reflection -- this is categorized as the positive feedback (↑).

Possible Global Warming Factor 3: the Intermolecular Collision

1. A molecule moves fast: while propagating, e.g., at 363 m/s for CO2, it collides with other molecules in the atmosphere 9 billions times per second (its mean free path is 4 * 10^-8 m in the atmosphere). Thus, the collisions result in the increase in the temperature of the atmosphere. By the way, temperature, T, can be described as T = (2/3)(mv^2/2)(1/k) where mv^2/2 is the kinetic energy of a molecule. According to the law of equipartition of energy, CO2 and H2O can move slowly and fast, respectively (rotations and vibrations, which can adsorbs and emits infrared, are omitted here, since those two have already been considered), since the molecular weights of CO2 and H2O are 44 g/mol and 18 g/mol, respectively. The 2.4 times faster move can result in the more (= 2.4 times) chance to exchange the energy. The specific heat of H2O is 4.19 J/g K at 20 oC when it is liquid (l), and 1.95 J/g K at 20 oC when it is gas (g): this means that the temperature rise can decrease the total heat capacity on earth due to the H2O(l) decrease and the H2O(g) increase, resulting in the temperature-rise acceleration, meaning this is categorised as the positive feedback (↑). The latent heat for H2O evaporation is, e.g., 2,454.2 J/g at 20 oC (2,258 J/g at 100 oC, but I would not imagine this catastrophe): this can delay the temperature rise. The specific heat of H2O is 4.22 J/g K at 0 oC when it is liquid (l), and 2.1 J/g K at 0 oC when it is solid (s), i.e., the ice: this means that the temperature rise can increase the total heat capacity on earth due to the H2O(l) increase and the H2O(s) decrease, resulting in the temperature-rise deceleration, meaning this is categorized as the negative feedback (↓). The latent heat for the ice melt is 333.5 J/g at 0 oC: this can delay the temperature rise. By the way, the specific heats of N2 and O2 are 1.0 J/g K and 0.9 J/g K at 20 oC, respectively. The concentration of N2 and O2 in air is high, roughly 99-3 = 96% in summer and 99-0.2 = 99.8% in winter.

Possible Global Warming Factor 4: the Vaporization of methane out of methane hydrate.

1. e.g., New Theory Behind Dozens of Craters Found in Siberia.