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Roger Pham
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@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.
@skierpage, Tesla is very important because only Tesla BEV's are selling, while the rest aren't. If Tesla is to make PHEV's, those would sell above and beyond what PHEV's are available now. Tesla does not have to invest any money to develop an engine. Just form a joint venture with an independent engine company, like Yamaha Engine company, who has engines available already, thus minimize the development cost. Making PHEV's will save Tesla $Billions in investment in battery production, and will allow profitability that Tesla is sorely lacking right now.
Ridiculous! H2 can be far easily transported via pipelines, similar to the pipeline transportation of Natural gas. Cargo transportation is most efficiently done by train on land, or by ships at sea. Period.
@Arnold, People who care about lower emission would try to drive on electricity as much as possible, and don't worry about the stated emission numbers. This brings up the second point: A PHEV would do better if it has as small an ICE as possible, while having a bigger battery to permit longer daily commute on all electricity. I feel that the 2.0 liter engine is too big, especially when mated with an 8-speed transmission. An 1-liter 3-cylinder engine would weigh half as much, and even a lot less when mated with a tiny CVT. BMW X3xDrive 30e does not take optimal advantage of dual-power-plant redundancy capability of a PHEV, due to having 2-wheel drive with the e-motor mated to the 8-speed transmission, instead of having 4-wheel drive with the engine driving the front axle and e-motor on the rear axle. So, if the transmission is to fail, the vehicle would be stalled, though with just engine failure, it can be driven using the e-motor alone, and vice-versa. BMW uses too big an engine which necessitates a too-big-and-heavy 8-speed transmission which adds a lot to weight and cost, thus significantly reducing the appeal of PHEV's, which should be leaned toward more electric than ICE. The engine should be downsized to a 1-liter 3-cylinder turbocharged, which is much lighter, AND the use of a small and very-light CVT transmission which is MUCH, MUCH lighter than a monstrous 8-speed transmission required to handle TWICE the engine torque, that of a 2-liter turbocharged engine instead of the torque of an 1-liter turbocharged engine. Imagine a predominantly-electric PHEV having: 1) 120-hp 3-cylinder turbocharged 1-liter engine with a small CVT in the front axle, 2) 130-hp e-motor on the rear axle 3) 15-kWh battery pack below the front seat or rear seat for ~45-mi AER. 4) 5-6-gallon fuel tank behind the battery pack. Total HP = 250 hp. Total Range: 300 miles. 0-60 mph acceleration = ~5 seconds, due to much-reduced weight than that of the BMW X3 PHEV, comparable in acceleration to that of the Tesla Model 3. Yet, it has 50% higher AER than the X3 PHEV. Now, then, a PHEV-version of Model 3 would be very cost-effective in comparison to the high cost of the long-range Tesla Model 3 right now. Without the engine and CVT, we would need additionally 55 kWh of battery in a long-range Model 3 for adequate range, PLUS 120-hp e-motor for fast acceleration. The engine and CVT cost around $5,000 while displacing around $15,000 in extra battery, e-motor, and inverter cost = net $aving of ~$10,000. So, a Model 3 in PHEV trim as above would cost $10,000 less than the BEV version. $45,000 - $10,000 = $35,000 with comfortable profit margin. Thus, the promise of $35,000 Model 3 would have been kept. So, a Model 3 PHEV would cost $35,000 in comparison to an equivalent BEV version costing $45,000, yet will offer full redundancies in both power plants as well as and energy sources. The dual-power-plant redundancy is very important as the vehicle ages and starting having problems with power train. A 10 yo BEV with a worn-out battery pack will head to the junk yard, while a PHEV will still be driven even with a worn-out battery pack.
@mahonj, >>>>>>>"The problem with renewable energy (Solar and wind) is that it is intermittent, while fossil based generation is "on demand", or dispatchable..." If we will have an overwhelming Solar and wind capacity that is over 4 times peak grid demand, with adequate long-distance power transmission capacity, then even with weak Solar and wind output, the grid can still be satisfied. We will thus have dispatchable DEMAND to replace dispatchable power generation. The USA has 1,000 GW of total grid generational capacity and consumes 4,000 TWh of electricity annually = <50% capacity factor, given that 1 yr = 8700 hrs. With solar at 22% and wind at 33% and equal mix, we would need about 1,600 GW. However, since grid electricity is only 1/4 of all energy consumed, we would need around 4,000 GW of Solar and wind combined to satisfy all energy demand, taking into account electrification of transportation and heat pump and combined heat and power to increase efficiency. At the current rate of 20 GW of new RE capacity yearly, it would take 200 years and around $6 Trillion USD in cost, because much less grid utility storage needed when we have so much excess Solar and Wind capacity available for the grid. However, if we would convert fossil fuels to Hydrogen while sequestering the CO2 right away and right down the oil and gas wells, and pump the H2 to the end users, we could stop CO2 emission into the air in much shorter time frame, while still building Solar and Wind at a faster rate, because the grid-excess S&W will be used to make H2, thus avoiding wasteful curtailment and bring back more money for S&W investors.
Continued from above: So, the easiest way to decarbonize fossil fuel and even waste biomass would be to steam reform them at nearby oil and gas fields, whereby the waste high-pressure and highly-concentrated CO2 stream is already ready to be sequestered down into depleted oil and gas wells nearby. The H2 produced at nearby the oil and gas fields would be pumped in pipelines to reach end-users, analogous to what would be done for natural gas. Just substituting zero-carbon H2 gas for the natural gas,for use by the end-users, that's all. The UK is considering going that route, to replace natural gas with H2, with CO2 sequestration if the H2 is made from hydrocarbon sources.
The two most energy-consuming and expensive steps in CO2 sequestration are: 1) separate the CO2 from very diluted l level in the air, and, 2) Compress the CO2 from atmospheric pressure to thousands of psi for sequestration. The use of higher-CO2 concentration in power-plant exhaust would make it less expensive than CO2 from the air, but still requires the costly compression step from atmospheric pressure to thousands of psi. However, the use of almost-pure CO2 from the process of steam reformation of natural gas, coupled with the very high pressures at thousands of psi already existed in the steam-reformation vessels means that: the use of H2 by end-users, when the H2 is produced from reformation of fossil fuel, would result in by far the easiest and least costly CO2 sequestration.
Good point, E-P regarding the use of synchronous motors fed by the frequency of the alternators to avoid the efficiency loss and the weight associated with AC to DC and then to AC conversion. So, we may have one turboshaft connected to one alternator to power one side of the aircraft, while the other turboshaft will do the same for the other side of the aircraft, with rapid switching to all motors power by one alternator should there be failure of one turboshaft. This setup may be competitive weight-wise and cost-wise with existing high-bypass turbofans, while exceeding in term of efficiency, especially much improved single-engine operation. Regarding your concern about having airflow over the tail surfaces, why not have some e-motors and props mounted on the tail surfaces also? In this way, we will have very positive attitude control of the aircraft regardless of airspeeds and wind gust. The use of ultra-capacitor to help spool up the turboshaft engines and the props rapidly coupled with very positive attitude control at all airspeeds can allow for rapid response to down-burst cells, wind gusts, and will increase safety. Furthermore, there will no longer be the problem of thrust asymmetry in the event of failure of one turboshaft engine, thus will further enhance safety and reduce pilot training time. Perhaps the Boeing 737-Max 8 should be the first airliner to be experimented with this new electro-turboshaft propulsion method, since it will solve the handling issue with the too big fan nacelles hanging way in front of the leading edges, as well as providing the efficiency needed to be competitive in the market. Go, Boeing, Go! Regarding the use of microwave energy beamed up from the ground, there might be issues with the effect of very high-energy microwave on the passengers and on avionics and on airframe heating. Perhaps you can enlighten us on these issues.
This is actually a very good way to improve efficiency of even large turbofan transport planes. This is how: Large turbofan transport planes need ridiculously-large nacelles to obtain ultra-high bypass ratio, but the large nacelles add drags and weight, plus the big heavy fans are also heavy and requiring another low-pressure turbine with shaft, and even another gear drive unit like the most recent Pratt&Whitney geared fan. The Airbus A400M turboprop transport that can cruise at 485 mph is proof that turboprop can fly fast. However, large propellers produce more vibration, noise, and more prone to failure due to their humongous size, and the mechanical gear boxes are also their weak link, that require more maintenance and higher failure risk. Much smaller and more numerous propellers driven by e-motors along wing leading edges can overcome the disadvantages of big gear-driven turboprops. So, we can a 10 or more smaller e-motor driven propellers all along the wing leading edges to obtain ultra-high bypass ratio without requiring humongous fan nacelles. We will only need two turboshaft units coupled with high-speed generators mounted in the nose of the aircraft. So, even with failure of one turboshaft unit, all the e-motors would be still functioning and can still generate 66% of the original thrust, thus single-engine climb performance would be far better than the failure of one turbofan unit in a twin-fan wing-mounted plane. Seems to be a promising concept.
ECI asked if it would be competitive for the electrolyzer equipment to operate at part-time basis? Answer: Electrolyzers are getting cheaper in production cost now, and also, you would want to use the ultra-pure electrolytic Hydrogen as transportation fuel whereby higher prices are allowable, instead of as replacement for natural gas in power generation. ECI further asked "Would it be cost competitive with pumped hydro....?" Answer: Dunno about pumped-hydro, but it is difficult to compete with natural gas as back-up power generation fuel, so transportation fuel will fetch higher prices. Pumped-hydro can still be used as short-term e-storage, while H2 from natural gas with CO2 sequestration at the source can be used for longer-term RE back-up. ECI further stated: "Given the low round-trip efficiency, it seems unlikely." Answer: The round-trip efficiency of H2 from grid-excess RE can match that of battery IF the Hydrogen will be used for heating, or combined power and heat applications. Efficiency of electrolysis if calculated on the HHV (Higher Heating Value) of H2 can be as high as 85%, and when used for space heating can result in nearly 100% efficiency, so the round-trip efficiency can be above 80%, which can match the round-trip efficiency of batteries and pumped-hydro.
Paroway stated: "This plan is meant to keep the oil industry as our masters. " Of course, the oil industry is already our master...what can we do about it? That 's why the US gov has no plan to combat GW, while raising the speed limits to 70-80 mph, and putting no additional taxes nor restriction on the sales of low-mpg SUV's and trucks, and has no plan for public transportation...etc... Short of a revolution in the USA and other oil-producing countries, our most realistic option would be to negotiate for the energy industry to move toward the Hydrogen Economy by at least producing hydrogen from fossil fuels at near oil and gas fields, and then immediately sequester the CO2 waste stream down in depleted oil and gas wells. Then, the Hydrogen can flow in pipeline systems to the end users, who will then use the Hydrogen for transportation, for combined power and heating in FC or combustion engines in distributed power generation due to the emission-free nature of H2, ...and for production of steel, concrete, fertilizer, and other industrial chemicals. It is FAR EASIER to decarbonize at the source than at the end users. E-P has reservation regarding storing H2 in underground natural gas reservoirs. However, due to the vast size of these formations with very high volume to surface ratio, we can simply coat the walls of these underground caverns with a thick coating to prevent leakage of H2 into the sulfur-based rock formation. That's all. So, to sum up, we can easily and cost-effectively achieve CO2-free energy by moving to the Hydrogen Economy, NO MATTER how the Hydrogen will be produced.
Indeed, the major selling points for long-range BEV's like Tesla are high performance and novelty, and not really about environmentalism. Most people don't much care about the environment. A hybrid (HEV) has been known to be cost-saving over a comparable non-hybrid, yet hybrids has not really been growing in sales, perhaps due to the higher initial cost and the fear of high cost of battery replacement and of repairs of the hybrid power train. The higher cost of a HEV will be more than offset by lower fuel cost, however, it is the fear of battery replacement and of repairs of the hybrid power train that has kept most people from purchasing HEV's, even though in the majority of cases, HV battery packs have been known to last for the life of the car, and that overall repairs for HEV power train have been a lot lower than repair costs of a transmission unit. Better public education will greatly help in this regard, if the governments want to protect the environment and energy security seriously, and NOT any budget-draining subsidies for cars with huge battery packs that can do more harms for the environment than helping it, especially when the Lithium is not even recycled due to the cost of recycling Lithium from Li-ion batteries..
@lad, The first gas turbines ever made ran on hydrogen. Future gas turbine using Liquid H2 can have precooling of intake air to gain efficiency by 25%. In combination with the lightness of LH2, future jet planes using LH2 can use 2.5 x less fuel per pound of payload.
@sd 6 kg of H2 would give an energy equivalent of 132 kWh of Li-ion battery. The 6-kg H2 tank should cost around $3,000 and 26 kWh of FC should cost around $200 x 26 = $5,200. So, the FC and H2 tank combined would cost around $8,200. On the other hand, 132 kWh Li-ion battery at $300 per kWh would have a price tag of $39,600. Ouch!!! So, the smart thing to have is the FC and H2 tank for range extension, instead of an additional 132 kWh of Li-ion battery. Just do a little math, my friend.
@EP and HD Whatever socio-racial problems there are in the USA, the horse has left the barn, the genie has gotten out of the bottle...We will have to endure for a while... THE number 1 peaceful solution for the long-term future of the USA is to limit welfare support to ONLY ONE child per mother. A welfare mother cannot keep reproducing illegitimate children one after another when taking advantage of hard-earned taxpayers' money. Any women on welfare should be on verifiable birth control like the IUD that can be identified via sonography scan, or a Norplant that can be verified physically. At the same time, the fertility rates for tax-paying parents should be boosted, in the form of lower income tax % for each additional child in the family. This would benefit tax-paying parents and give the incentive to have more kids, while lower incentive for fertility for non-tax-paying families. This will lead to social prosperity and improving social sustainability. The current welfare situation and the demographic trend are not sustainable. Over time, the lower fertility rate of welfare mothers in comparison to that of non-welfare mother will reduce the proportion of troublesome population. As far as dealing with increase in VMT, we will have to push for rapid decarbonization of transportation...The horse has left the barn for 7-8 decades now, ever since GM-Oil conglomerate bought electrolley lines and cars and crushed them, while urban planning policies allowed huge urban sprawls, including zoning policies that forbid mingling of business district with residential area, plus socio-racial disharmony leading to abandoning of inner cities of the middle class . Let's guess who's the boss...who's in control of the goverment, eh? Where I came from, many people lived right above their shops, offices, or small businesses, thus significantly reduces commuting requirement. We used to live on a 3-story house that the 1st floor was used for business office, thus no commuting for my parents. Why can't that be done for the USA's?