This is Roger Pham's Typepad Profile.
Join Typepad and start following Roger Pham's activity
Join Now!
Already a member? Sign In
Roger Pham
Recent Activity
@E-P, Chevron and Aramco are both energy companies, so obviously they are interested in Hydrogen, which will replace fossil fuel usage by the end-users to avoid atmospheric CO2 emission to meet Global Warming target. At the present, fossil fuel can be steam-reformed to make H2, with the almost-pure and high-pressure CO2 by-product ready for injection into existing oil and gas wells to avoid CO2 emission into the atmosphere. Of course, when electrolytic H2 from RE will be cost-competitive, then fossil fuel will be phased out. Either way, H2 is the most viable way to decarbonize future energy consumption by the end-users NOW, even with continual consumption of fossil fuel, while waiting to ramp up solar and wind collectors, which will take many decades.
Good point, TLJ. I was about to say those points. I'm still waiting for the likes of the hybrid trim of the Camry or Avalon having a lift-back for more luggage capacity and more versatile cargo handling. The specs of this RAV4 Prime are all good, but I just don't like the boxy appearance, and the low aerodynamic efficiency that will really show up when you are trying to keep up with interstate traffic traveling at 80 mph. On the other hand, the current Prius looks very sleek and very aerodynamic, but it is a tad on the small size, and especially with anemic power of merely 121 hp. Toyota should be planning on applying the existing 180-hp hybrid power train of the hybrid Corolla 2,0 liter to the Prius chassis to relieve the anemic performance of the Prius and to regain lost market share. A Camry hybrid or Avalon hybrid with the lift-back design and high aerodynamic efficiency like the Prius would be PERFECT.
@EP, Furthermore, EROI of solar PV is found to be around 16 and getting higher, while EROI for wind is around 20. Very doable.
@EP, You assume Natural Gas mixed with H2 at various proportions, but in the UK, the plan is to replace NG totally with 100% H2, so that the gas combustion appliances only need to have the gas jet changed once, to increase the fuel flow rate with respect to air intake. So, only H2-FC is necessary, and not having to deal with NG-FC at all. Your assumption about NG pipeline already run at maximum capacity does not hold true at all times of the year, depending on the season. Summer and Winter demand for NG is much higher than Spring and Fall, however, with the case of H2, it ain't necessarily so. This is because a society depending on a 50:50 mix of solar vs wind will have a lot of solar energy in the summer, so doesn't need H2 in the same amount as a society depending heavily on NG for electricity, and wind is plentiful in the winter, so if 50% of energy comes from wind, then winter will not need H2 as much as needing NG, especially with distributed power and heat generation. Flow speed of NG in long-distance pipelines must be kept low in order to keep drag loss to manageable level. H2 will be produced mostly locally, and stored in nearby geologic storage, so will only travel a small fraction of NG pipelines, thus can flow several times faster for a given pressure drop in comparison to a long-distance pipeline, when needing to meet occasional periods of high demand. Hopefully this time less BS than before, and thanks for your valuable feedback.
@EP: The UK is in the process of replacing natural gas with H2 in their piping system. They have many publications which should answer your many questions. The use of H2 to replace NG is no longer an academic issue, but is being implemented as the quickest way to eliminate CO2 and methane emission, the two main GHG that cause the most heat retention. The NG is being turned into H2 right from the source, while the resulting high-pressure and pure CO2 stream is immediately injected down into oil and gas wells, at next to zero additional cost in efficiency nor money, thus largely eliminating CO2 and natural gas emission from the NG distribution system. Talking about killing 2 birds with one stone. Briefly, the low energy content of the H2 is made up for by the very high speed of sound in H2 at 1270 m/s vs NG at 446 m/s, meaning that the H2 can be flowed at ~3 times the maximum speed that NG can be flowed in a pipeline before reaching non-compressibility issue. Furthermore, H2 has lower viscosity than NG, permitting high-speed flow without incurring much more friction loss. The lower volumetric storage density of H2 vs NG is made-up for by: 1.. The combination of solar and wind which complement one another, such that summer is abundant in solar but winter is more abundant in wind, thus greatly reduce the seasonal e-storage quantity, in comparison to dependency to fossil fuel as of now. 2.. The use of combined power and heat in distributed generation setting in the winter, that permits charging of EV's at night while using the waste heat for bed-room heating, as well as evening electricity use while waste heat used for hot-water heating. This is more energy-efficient than the waste of 50% of the natural gas' thermal energy by the power plant during power generation and power transmission. 3.. Multizone home heating and home A/C use can reduce energy consumption to 1/2-1/3 of current home energy consumption for cooling and heating. 4.. The use of ice as thermal energy storage for home cooling can significantly reduce the use of H2 or natural gas for home cooling during sun-down period.
@EP: >>>>>"Your mass solar farm is in darkness when your demand peak hits, Roger. What are you going to do about that?" Answer: Produce Hydrogen during solar peak, at 82% efficiency LHV and as much as 95% efficient HHV, by using Sunfire or H2Pro electrolysis techs. Store the H2 within the local residential piping system for natural gas, which can tolerate even 100% H2. Seasonal quantity of H2 can be stored in existing underground natural gas storage system. In the evening, fire up the residential fuel cells for electricity while the waste heat is used for making hot water for bathing, dish washing and laundry. At 95%-efficient electrolysis, calculated based on HHV, the round trip efficiency can be above 90%, which can easily rival the most efficient battery storage system. In winter nights, the home-based FC can charge your EV while the waste heat can keep your room warm. Summer A/C cooling energy can be stored as ice, to be used to cool the house later, since ice is the cheapest form of thermal energy storage. So, a water/ice tank is needed nearby the outdoor A/C condenser unit to produce ice using daytime solar energy. Even with nuclear energy, energy storage is still necessary, because peak demand is usually more than twice the average demand, and a nuclear power station should be run at near peak output to recoup the high investment cost. So, we will still need massive grid-utility energy storage capacity at seasonal scale, too big to be satisfied by battery alone, because spring and fall use far less energy than summer and winter, while the nuclear output is constant. Besides, we will still need to make Hydrogen from nuclear energy for making fertilizer, chemical feedstock, steel furnace, and to power surface transportation either directly or combined with CO2 to make liquid fuels. There is now at least 2 separate techs for storing H2 at 4-5 times the volumetric density of previous, or twice the density of liquid H2, but at only 10-120 bar room temperature, instead of at 700 bar. So, we should look at the H2 economy as an enabler of both RE and Nuclear Energy and not as an opposition. H2 and battery should complement each other and should not be viewed as being in competition to one another.
@EP and Thomas, PV panels could be installed over existing parking lots, departments stores, supermarkets, apartments, and warehouses. For example, let's take the case of Los Angeles, CA, have 4 million people over 503 sq mi area = 1,287 sq km, having peak electricity demand of 6,500 MW, with average demand around 45% = peak x 4,000 hrs annually. Solar capacity factor in that region average around 2,000 hrs annually over rated capacity, thus is roughly 1/2 of average demand, thus will need around 13,000 MW of nameplate solar capacity. Each square km = 1,000,000 sq m and at 20% efficiency = 200 MW in nameplate capacity. Thus, dividing the 13,000 MW capacity needed over 200 MW per sq km = 65 sq km. Thus, out of a total surface area of 1,287 sq km of LA city, it clearly NOT difficulty to find 65 sq km area of parking lots, apartments, warehouses, factories, supermarkets and department stores to mount solar PV panels. The thing is, you can't put your nuclear power station anywhere within LA city limit, thus the beauty of solar energy.
Let me sum up the specs of these technologies: 1.. H2Pro: 30% more H2 produced per kWh consumed, as compared to current tech. Half of CAPEX per kW, and not requiring precious metal, and the H2 is released at different time than the O2 gas, thus increase safety and reduce construction cost and maintenance cost. 2. GRZ Technologies: When hydrogen molecules are put in contact with the storage material, the molecules are dissociated in hydrogen atoms. These atoms are then absorbed in the interstitial sites of the metallic compound. This process occurs at near-ambient pressure (below 10 bar), is extremely safe and 100% reversible. The hydrogen density achieved in this state is extremely high, twice as high as liquid hydrogen and four times higher than pressurized gas. This allows practical packaging of H2 storage in refueling stations, cars and bikes without taking up more space than current gasoline storage system. The much lower pressure required here means lower cost, less maintenance, and higher reliability for the H2-filling system.
Just use Hydrogen directly, either in combustion engine or in fuel cell.
So, steel gears are cheaper than copper wiring and permanent magnets.
The Prius badly needs the 2.0 liter 180 hp power train to avoid sagging sales in the USA.
Low cost low grade solar heat can also be used to produce steam if solar electricity is to be used to make hydrogen. The waste heat from the solid oxide electrolyzer can also be recycled to make steam.
Yoatmon, of course, EE will be used directly whenever possible, and only stored when there is excess. Hydrogen is needed in many industrial applications, and if made from RE, will reduce CO2 emission.
@E-P, Hydrogen has been used safely in various major industries for over 100 years. Are we suddenly forget how to use Hydrogen safely? Or is there some foul play involved?
@EP, On Higher Heating Value (HHV) of hydrogen, the efficiency of room-temp electrolysis can be above 85%. This is important, because when the Hydrogen is used for room heating and for combined power and heat, the round-trip efficiency can be as much as 80%. Now then, if low-grade waste heat or solar heat is applied to evaporate the water before electrolysis, aka steam electrolysis, even the Lower Heating Value (LHV) of Hydrogen's efficiency can be as high as 85% WRT electrical energy input, for low-temp electrolysis, or even higher, with efficiency above unity, with high-temp electrolysis.
>>>>>"Coal. The filthiest and most polluting fuel we've got." That's why hydrogen is necessary, in order to leave all the filth behind, and just use the clean H2 from home heating, industrial use, power generation, and transportation. All the ash, mercury, arsenic, radioactive material from coal can be reclaimed for industrial use, while the CO2 can be sequestered deep underground as supercritical fluid. Even if we go nuclear, you will still need to produce H2 from nuclear energy for many roles that electricity cannot fulfill.
It is spurious to project Hydrogen cost of transmission, distribution and dispensation to cost $4.10 per GGe, when it could cost a lot less if transmitted, distributed and dispensed Hydrogen in similar fashion to natural gas. CNG near me costs around $2.00 per GGe, while wholesale price of NG is around $6 per MMBTU = $0.67 per GGE, so only $1.30 for transmission, distribution and dispensation per GGe. Ammonia production is not 100%-energy-efficient, may be around 50%-70% meaning that it would cost more in Hydrogen consumption and/or energy input, and it still costs a lot to produce Ammonia from Hydrogen, factoring facility cost and labor cost, when it would be simpler to consume the Hydrogen directly.
>>>>>"Why would anyone use hydrides at 10.5% H2 by weight when you've got ammonia at 17.8%?" Answer: Because Ammonia is not Hydrogen, when Hydrogen can be flowed in pipelines from sources to all end users with similar ease as Natural gas. Ammonia is too toxic for widespread usage by end-users. >>>>>>>"Furthermore hydrogen pipelines are considerably more expensive than natural gas pipelines because of the tendency of H2 to embrittle steel and other metals. " Answer: 1) Only large high-pressure Hydrogen pipelines needs to be made out of stainless steel instead of carbon-steel. Local low-pressure piping network for natural gas can accept 100% Hydrogen without problem. 2) The cost of steel is only a fraction of about 1/4 of the total cost of natural gas pipeline construction, so even more expensive stainless steel required for Hydrogen would not be prohibitive. 3) Furthermore, when new Hydrogen pipelines are to be built on the right-of-way of existing natural gas pipelines, the cost of permit and right-of-way acquisition will be avoided, thus can represent significant cost saving. 4) Many natural gas pipelines are old and are almost due for replacement anyway, so we can subtract this cost from the additional cost of build out a new H2 pipeline transportation network.
Thanks, Peter, for pointing out the MTZ paper, but I don't have to read it, since I'm quite familiar with the working of electro-hydraulic valve actuation system. Koenigsegg Freevalve camless system is an example of such arrangement. But, if you feel that the new system by Empa is a major advancement from existing systems, please kindly let us know some detail. Thank you in advance.
The high-temperature PEM FC is a major advancement, permitting better waste heat recuperation and reducing the size of the radiator and makes for a more compact installation. For combined heat and power application, the high-temp waste heat can be used for process steam that is useful in industrial application, and the high-temp waste heat can also provide for efficient vapor-absorptive refrigeration with COP as high as 0.8-1.2. However, If global warming is the issue, Hydrogen should be used directly instead of using Methanol. This is because Hydrogen is carbon-free and does not emit CO2, unlike the use of Methanol or any other carbon-containing fuels. Even if Hydrogen is produced from fossil fuel or waste biomass, the CO2 resultant from the steam reformation process can be directly and immediately sequestered into depleted oil and gas wells, thus no CO2 emission. The use of waste biomass to produce Hydrogen with CO2 sequestration will result in CO2 negative process equivalent to direct removal of CO2 from the atmosphere. Due to the advancement of manganese hydride matrix that can store H2 at 1,800 psi with much higher density than previously, H2 will find practical application in the transportation sector. For stationary applications and for H2-filling stations for vehicles, H2 can be substituted for natural gas and can be transported to the end-users with relative ease similar to the availability of natural gas. So, future emphasis on energy use should focus on the Hydrogen Economy as the principal approach to halt CO2 emission to combat Global Warming.
>>>>>>"PHEVs with bio synthetic fuels would do nicely, however getting people to adopt those is another thing entirely." Answer: Good point! If the US gov is not being influenced by big oil, then, in the goal of energy security, additional federal sales tax and tax credit can be levied on new vehicles based on MPG and MPGe rating. For example, $100 for every MPG below 50 mpg. So, a vehicle with 25 MPG rating would be assessed an additional $2,500 in tax at the point of sale, while a vehicle with 75 MPG would receive a $2,500 tax credit. This would immediately make a hybrid cost competitive with a non-hybrid, PHEV's and BEV's would be cheaper to buy, and would make big SUV's and pick-up trucks less popular. Quite simple...
An HEV running on biomethane, bioethanol, biodiesel, or renewable H2 is also a sustainable solution.
The Eviation Alice is an All-Electric 9-seat passenger plane having 8,000 lbs of battery out of 14,000-lb takeoff weight, having a range of 1,000 km. Let's consider a hypothetical Fuel Cell alternative to the 8,000-lb of battery, thanks to a recent discovery of a Manganese Hydride complex that can store Hydrogen at 10.5% weight percentage. Given 920 kWh battery capacity which translate to 920 kWh / 22 kWh per kg of H2 = 41 kg of H2. 41 kg divided by 10.5% = 398 kg = 876 lbs. Needs also 450 kW of fuel cells at 1 kg per kW = 450 kg = 990 lbs. Total e-storage system weight = 876 + 990 = 1866 lbs. This is very light in comparison to the 8,000 lbs of battery required to travel 1000 km, so wings, tail, and e-motors and inverters can be downsized, result in a lot of weight reduction in airframe weight and motor + inverter weigh. Maximum Takeoff Wt will be around half of current, at around 8,000 lbs, and thus will consume a lot less energy per mile, permitting a total range as far as 1,700 km, which is more in line with petroleum powered planes of this size, and can be refueled almost as fast, and not so slow as with battery recharging. The waste heat from the fuel cells can be harvested for cabin heating and anti-icing purpose on all forward-facing surfaces, and not wasted at all.
Why bother? Just use hydrogen, which can burn very lean without misfire.
@yoatmon, Hydrogen has been transported via piping for over a century without problem. Before natural gas was discovered, cities used "town gas" which contains high proportion of Hydrogen. Town gas was made from coal gasification and was transported to each house via soft-steel piping system. When natural gas was discovered, then natural gas was used in the same piping system, instead of "town gas". Losses of Hydrogen in pipeline system has been negligible. "cracking" of natural gas releases CO2 at high pressures and at high concentration that is ready for injection into depleting oil and gas wells, at almost NO further cost. By contrast, CO2 sequestration from power plants is very expensive due to the high cost of separating the CO2 from the flue gas and compression of this CO2 at atmospheric pressure. So, the best way to eliminate CO2 emission now is to make H2 from fossil fuel, and immediately sequester this CO2, while transport the H2 to the end users.