1 00:00:04,120 --> 00:00:07,160 Speaker 1: Get in touch with technology with tech Stuff from how 2 00:00:07,200 --> 00:00:14,040 Speaker 1: stuff works dot com. Hey there, and welcome to tech Stuff. 3 00:00:14,040 --> 00:00:16,919 Speaker 1: I'm your host, Jonathan Strickland. I'm an executive producer and 4 00:00:16,920 --> 00:00:22,079 Speaker 1: a love of all things tech. And on November I 5 00:00:22,160 --> 00:00:26,479 Speaker 1: ran across an article titled quote can we produce enough 6 00:00:26,640 --> 00:00:31,120 Speaker 1: green hydrogen to save the world? End? Quote? And I thought, 7 00:00:31,920 --> 00:00:34,559 Speaker 1: I haven't done an episode about hydrogen and the proposed 8 00:00:34,640 --> 00:00:37,240 Speaker 1: hydrogen economy for quite some time. It might be a 9 00:00:37,280 --> 00:00:40,800 Speaker 1: good sign to revisit this topic and remind everyone what 10 00:00:40,920 --> 00:00:44,360 Speaker 1: it's all about, because when it comes to conversations about 11 00:00:44,720 --> 00:00:49,800 Speaker 1: transitioning away from a dependence on fossil fuels, hydrogen is 12 00:00:49,840 --> 00:00:53,760 Speaker 1: frequently part of that conversation. Today, we're gonna explore why 13 00:00:53,800 --> 00:00:57,960 Speaker 1: that is, and whether we can in fact produce enough 14 00:00:58,240 --> 00:01:01,520 Speaker 1: of it responsibly in a green way to create a 15 00:01:01,520 --> 00:01:06,959 Speaker 1: true hydrogen economy. Spoiler alert, that's just one component of 16 00:01:07,000 --> 00:01:09,959 Speaker 1: a hydrogen economy. I'll talk a lot about that in 17 00:01:10,000 --> 00:01:15,920 Speaker 1: this episode. First, we gotta just lay some groundwork, right. 18 00:01:16,000 --> 00:01:20,760 Speaker 1: Hydrogen is the most abundant element in the universe. It's 19 00:01:20,840 --> 00:01:25,199 Speaker 1: what stars are made out of. According to the Los 20 00:01:25,280 --> 00:01:28,840 Speaker 1: Alamos National Laboratory, if you were to gather all the 21 00:01:28,920 --> 00:01:31,560 Speaker 1: atoms in the universe all the matters. So you've got 22 00:01:31,600 --> 00:01:34,839 Speaker 1: all the atoms in the universe all in one room, Well, 23 00:01:34,880 --> 00:01:37,600 Speaker 1: it would need to be a really big room, but 24 00:01:38,240 --> 00:01:41,720 Speaker 1: more than nine percent of all those atoms in that 25 00:01:41,840 --> 00:01:44,839 Speaker 1: room would be hydrogen. So at first you might think 26 00:01:45,120 --> 00:01:48,120 Speaker 1: that means we're lousy with the stuff here on Earth, 27 00:01:48,640 --> 00:01:52,279 Speaker 1: and we kind of are. But there's some other things 28 00:01:52,320 --> 00:01:56,120 Speaker 1: about hydrogen that makes that whole plentiful thing a little 29 00:01:56,120 --> 00:01:59,480 Speaker 1: more misleading when it comes to our day to day experience. 30 00:02:00,160 --> 00:02:04,880 Speaker 1: So first, pure hydrogen has a boiling point of minus 31 00:02:04,960 --> 00:02:09,520 Speaker 1: two hundred fifty two point nine degrees celsius. That's minus 32 00:02:09,880 --> 00:02:14,520 Speaker 1: four hundred twenty three point two degrees fahrenheit. That means 33 00:02:14,800 --> 00:02:19,959 Speaker 1: anything warmer than that extremely cold temperature will cause hydrogen 34 00:02:20,040 --> 00:02:24,160 Speaker 1: to boil off into a gas. To make hydrogen a liquid, 35 00:02:24,520 --> 00:02:27,840 Speaker 1: you would have to cool it down to thirty three kelvin. 36 00:02:28,440 --> 00:02:33,280 Speaker 1: Zero kelvin represents absolute zero. That's when you essentially have 37 00:02:33,600 --> 00:02:39,359 Speaker 1: no molecular movement at all. Absolute zero is colder than 38 00:02:39,440 --> 00:02:43,079 Speaker 1: empty space, which is somewhere around two point seven kelvin, 39 00:02:43,520 --> 00:02:47,760 Speaker 1: So thirty three kelvin is toasty in comparison, but it's 40 00:02:47,800 --> 00:02:51,720 Speaker 1: still colder than anything you're gonna find occurring naturally on 41 00:02:51,760 --> 00:02:56,880 Speaker 1: our planet. So on Earth, unpressurized pure hydrogen is going 42 00:02:56,919 --> 00:03:00,280 Speaker 1: to be in gas form, and this is a problem 43 00:03:00,360 --> 00:03:05,520 Speaker 1: because hydrogen is also the lightest element. The heavier elements 44 00:03:05,520 --> 00:03:09,440 Speaker 1: in Earth's atmosphere will push down and hydrogen will move 45 00:03:09,639 --> 00:03:14,360 Speaker 1: up higher and higher until it actually escapes Earth's gravity, 46 00:03:14,720 --> 00:03:20,400 Speaker 1: so pure hydrogen will float off into space. Capturing hydrogen 47 00:03:20,600 --> 00:03:24,560 Speaker 1: from the atmosphere isn't really a practical solution because of this. 48 00:03:25,280 --> 00:03:29,840 Speaker 1: So hydrogen also has a strong tendency to bond with 49 00:03:29,960 --> 00:03:33,640 Speaker 1: other elements, and that's really another very important thing. So 50 00:03:33,680 --> 00:03:36,680 Speaker 1: we can get to hydrogen here on Earth, but it's 51 00:03:36,760 --> 00:03:40,880 Speaker 1: bonded to other stuff Like two Hydrogen's can bond with 52 00:03:41,080 --> 00:03:45,200 Speaker 1: an oxygen atom and form water H two O. So 53 00:03:45,240 --> 00:03:47,720 Speaker 1: more on that in a bit as that's key to 54 00:03:47,800 --> 00:03:52,120 Speaker 1: the challenge of making a working hydrogen economy is figuring 55 00:03:52,120 --> 00:03:55,320 Speaker 1: out how to get hydrogen out of these compounds and 56 00:03:56,000 --> 00:03:59,480 Speaker 1: elements and things, not elements, but you know, mixtures. So 57 00:04:00,320 --> 00:04:05,400 Speaker 1: there are three common isotopes of hydrogen. The ordinary, boring 58 00:04:06,080 --> 00:04:09,480 Speaker 1: pure hydrogen that we tend to talk about is called protium, 59 00:04:09,520 --> 00:04:13,400 Speaker 1: and that consists of one proton that is orbited by 60 00:04:13,480 --> 00:04:19,000 Speaker 1: one electron. So the nucleus of pure hydrogen protium isotopes 61 00:04:19,800 --> 00:04:23,479 Speaker 1: is just a proton. Then you have deuterium that one 62 00:04:23,520 --> 00:04:26,479 Speaker 1: adds a neutron to the nucleus, so now you've got 63 00:04:26,480 --> 00:04:31,040 Speaker 1: one proton, one neutron in the nucleus orbited by one electron. 64 00:04:31,360 --> 00:04:35,240 Speaker 1: Then you have tritium that's a radioactive isotope and it 65 00:04:35,279 --> 00:04:39,839 Speaker 1: has a nucleus with one proton and two neutrons orbited 66 00:04:39,839 --> 00:04:44,040 Speaker 1: by a single electron. This stuff does occasionally form in 67 00:04:44,120 --> 00:04:48,039 Speaker 1: Earth's atmosphere when cosmic rays interact with the air, but 68 00:04:48,160 --> 00:04:50,880 Speaker 1: it has a pretty darn short half life. It's just 69 00:04:51,520 --> 00:04:54,560 Speaker 1: half life of twelve point three years. So when you 70 00:04:54,600 --> 00:04:57,120 Speaker 1: pair that with the fact that it's super light, so 71 00:04:57,120 --> 00:05:02,919 Speaker 1: little eventually flowed off into space. It's also very uncommon 72 00:05:03,000 --> 00:05:07,240 Speaker 1: for cosmic ray interactions. They aren't super commonplace. There's very 73 00:05:07,240 --> 00:05:11,280 Speaker 1: little chance for any significant amount of tritium to accumulate 74 00:05:11,320 --> 00:05:16,400 Speaker 1: in the atmosphere before it decays. Back in sixteen seventy one, 75 00:05:17,000 --> 00:05:21,200 Speaker 1: a philosopher and intellectual named Robert Boyle was doing some 76 00:05:21,360 --> 00:05:25,000 Speaker 1: exploratory research. He was using iron and dipping it into 77 00:05:25,080 --> 00:05:28,000 Speaker 1: different types of acid, and he saw that the reaction 78 00:05:28,200 --> 00:05:32,200 Speaker 1: in one of these combinations produced some bubbles some gas. 79 00:05:32,920 --> 00:05:36,520 Speaker 1: Many folks will call boil the the father of chemistry, 80 00:05:36,560 --> 00:05:39,400 Speaker 1: but at this point his observation mostly just consistent of 81 00:05:39,680 --> 00:05:43,240 Speaker 1: it's a gas man, you know anything more about it. 82 00:05:43,320 --> 00:05:48,960 Speaker 1: Almost a century later, Henry Cavendish, another philosopher and scientists, 83 00:05:49,240 --> 00:05:54,160 Speaker 1: identified hydrogen gas as a distinct element. The French chemist 84 00:05:54,320 --> 00:05:58,960 Speaker 1: Antoine la Vasier gave hydrogen its name. Now, the earliest 85 00:05:59,000 --> 00:06:02,279 Speaker 1: record I could find of a gas balloon that used 86 00:06:02,360 --> 00:06:07,280 Speaker 1: hydrogen as the lifting agent dates to seventeen eighty three 87 00:06:07,320 --> 00:06:11,280 Speaker 1: in Paris, but hydrogen was used for balloons and airships 88 00:06:11,360 --> 00:06:15,960 Speaker 1: for decades until really the Hidden Hindenburg disaster in nineteen 89 00:06:16,000 --> 00:06:20,159 Speaker 1: thirty seven that scared people quite a bit and stopped 90 00:06:20,200 --> 00:06:22,960 Speaker 1: a lot of people from using hydrogen as a lifting agent. 91 00:06:23,080 --> 00:06:27,080 Speaker 1: Hydrogen gas, by the way, is extremely flammable in the 92 00:06:27,120 --> 00:06:31,560 Speaker 1: presence of oxygen. So the Hindenburg caught fire as it 93 00:06:31,600 --> 00:06:34,000 Speaker 1: was docking with a mooring mast, and it was a 94 00:06:34,040 --> 00:06:37,839 Speaker 1: massive fire. It killed thirty six people, including one person 95 00:06:37,880 --> 00:06:40,040 Speaker 1: on the ground. There were a lot of people who 96 00:06:40,040 --> 00:06:43,799 Speaker 1: were on the Hendenberg who survived with some with severe injuries. 97 00:06:43,800 --> 00:06:47,240 Speaker 1: But still that's a pretty awful disaster. And it was 98 00:06:47,279 --> 00:06:52,600 Speaker 1: caught on film and there was a radio uh presenter 99 00:06:52,680 --> 00:06:56,000 Speaker 1: who was talking through the whole thing. If you've ever 100 00:06:56,040 --> 00:06:58,400 Speaker 1: heard the phrase, oh the humanity that comes from the 101 00:06:58,480 --> 00:07:04,039 Speaker 1: Hindenburg disaster, and it truly was a spectacular catastrophe that 102 00:07:04,200 --> 00:07:09,120 Speaker 1: tragically killed many people. Now, there are several hypotheses as 103 00:07:09,120 --> 00:07:12,920 Speaker 1: to what actually started this fire, but it was definitely 104 00:07:13,040 --> 00:07:15,760 Speaker 1: the hydrogen that provided the fuel for it to spread 105 00:07:15,800 --> 00:07:19,440 Speaker 1: so quickly and to cause such a disaster. So disasters 106 00:07:19,440 --> 00:07:23,560 Speaker 1: like the Hindenburg definitely raised huge warning flags with anything 107 00:07:23,560 --> 00:07:27,600 Speaker 1: associated with hydrogen and fuel in many people's minds, and 108 00:07:27,640 --> 00:07:31,360 Speaker 1: it persists to this day. There are people who say, well, 109 00:07:31,400 --> 00:07:34,120 Speaker 1: we don't want to invest in any sort of hydrogen 110 00:07:34,480 --> 00:07:39,280 Speaker 1: approach to energy storage because of the possibility of another 111 00:07:39,400 --> 00:07:44,120 Speaker 1: Hindenburg like disaster. Now, in the eighteen hundreds, a mixture 112 00:07:44,200 --> 00:07:47,280 Speaker 1: with hydrogen was used as gas for street lamps, so 113 00:07:47,280 --> 00:07:50,920 Speaker 1: it was actually being used as a form of fuel, 114 00:07:51,240 --> 00:07:54,280 Speaker 1: And in eighteen thirty nine Sir William Robert Grove would 115 00:07:54,280 --> 00:07:57,120 Speaker 1: conduct some experiments that led to the development of hydrogen 116 00:07:57,200 --> 00:08:01,400 Speaker 1: based fuel cells. So we'll talk more about fuel cells 117 00:08:01,440 --> 00:08:05,080 Speaker 1: in a little bit, But first, burning hydrogen gives off 118 00:08:05,200 --> 00:08:08,920 Speaker 1: water vapor and some other trace by products depending on 119 00:08:09,120 --> 00:08:11,520 Speaker 1: how you're burning. If you're burning it with pure oxygen, 120 00:08:11,800 --> 00:08:16,680 Speaker 1: you get water vapor. If you burn it in atmospheric conditions, 121 00:08:16,920 --> 00:08:21,400 Speaker 1: you'll get some small byproducts like various hydrogen oxides. It 122 00:08:21,440 --> 00:08:24,320 Speaker 1: all depends upon the composition of the air at that point, 123 00:08:24,720 --> 00:08:29,280 Speaker 1: but it does not produce carbon dioxide like burning fossil 124 00:08:29,360 --> 00:08:32,880 Speaker 1: fuels does. So it seems like hydrogen would be a 125 00:08:32,920 --> 00:08:36,120 Speaker 1: super awesome fuel source for us to go with if 126 00:08:36,720 --> 00:08:39,600 Speaker 1: we could be reasonably certain that the method we're using 127 00:08:39,880 --> 00:08:43,440 Speaker 1: would contain this reaction and not result in a in 128 00:08:43,480 --> 00:08:47,240 Speaker 1: a Hindenburg like disaster. But that's something we can totally do. 129 00:08:47,360 --> 00:08:50,240 Speaker 1: We can do that. I mean, cars are driving around 130 00:08:50,320 --> 00:08:54,600 Speaker 1: using gasoline as fuel, and gasoline is flammable, So why 131 00:08:54,640 --> 00:08:57,319 Speaker 1: don't we just switch to hydrogen. I mean, it's it's 132 00:08:57,320 --> 00:09:01,480 Speaker 1: the most plentiful stuff in the universe and it burns lean. Now, granted, 133 00:09:01,520 --> 00:09:04,640 Speaker 1: water vapor is a greenhouse gas, we have to accept this, 134 00:09:05,320 --> 00:09:08,280 Speaker 1: but water vapor also can incorporate into the water cycle 135 00:09:08,400 --> 00:09:11,280 Speaker 1: on Earth and out of all the greenhouse gases. We 136 00:09:11,360 --> 00:09:16,040 Speaker 1: actually understand water vapors roll in greenhouse gases the least, 137 00:09:16,520 --> 00:09:19,880 Speaker 1: But what's the hold up with hydrogen? While the big 138 00:09:19,880 --> 00:09:23,040 Speaker 1: one is that most of hydrogen on Earth is bound 139 00:09:23,040 --> 00:09:26,960 Speaker 1: together with other stuff like water that hydrogen and oxygen 140 00:09:27,679 --> 00:09:32,200 Speaker 1: or hydrocarbons like the hydrocarbon is an organic compound made 141 00:09:32,280 --> 00:09:34,840 Speaker 1: up of hydrogen and carbon. So if you have a 142 00:09:34,840 --> 00:09:38,520 Speaker 1: carbon atom and four hydrogen atoms, you would have methane. 143 00:09:39,000 --> 00:09:42,080 Speaker 1: To use pure hydrogen as fuel, you first have to 144 00:09:42,120 --> 00:09:46,040 Speaker 1: find a way to shake those hydrogen atoms loose from 145 00:09:46,040 --> 00:09:50,200 Speaker 1: those molecular bonds. So that means to produce hydrogen gas, 146 00:09:50,679 --> 00:09:55,080 Speaker 1: we first have to pour some energy into compounds that 147 00:09:55,120 --> 00:09:57,679 Speaker 1: have hydrogen in them to break those molecular bonds. You 148 00:09:57,720 --> 00:09:59,280 Speaker 1: gotta come up with a good way to do that 149 00:09:59,640 --> 00:10:01,880 Speaker 1: so that in the end of the day, the energy 150 00:10:02,080 --> 00:10:06,040 Speaker 1: stored in the hydrogen gas that you have harvested is 151 00:10:06,160 --> 00:10:09,480 Speaker 1: more than the amount of energy you used to get 152 00:10:09,520 --> 00:10:12,360 Speaker 1: the gas in the first place. Otherwise you have a 153 00:10:12,480 --> 00:10:16,000 Speaker 1: net loss and energy. If you pour more energy into 154 00:10:16,160 --> 00:10:19,520 Speaker 1: making the hydrogen gas, then you would get out of 155 00:10:19,559 --> 00:10:24,840 Speaker 1: consuming the hydrogen gas. You're losing energy. We call this 156 00:10:25,400 --> 00:10:28,360 Speaker 1: a bad thing. This is true for all fuels, by 157 00:10:28,360 --> 00:10:30,520 Speaker 1: the way. So if it cost us more energy to 158 00:10:30,520 --> 00:10:34,360 Speaker 1: get petroleum and to refine that petroleum into fuel, then 159 00:10:34,559 --> 00:10:37,840 Speaker 1: the petroleum fuel itself could store we would not be 160 00:10:37,960 --> 00:10:40,480 Speaker 1: using fossil fuels to begin with, because we would be 161 00:10:40,520 --> 00:10:43,679 Speaker 1: losing energy. We would instead say, why don't we use 162 00:10:43,760 --> 00:10:47,199 Speaker 1: whatever it is we are relying upon to get the 163 00:10:47,240 --> 00:10:50,120 Speaker 1: petroleum in the first place as our energy source. But 164 00:10:50,200 --> 00:10:53,240 Speaker 1: that's not the case. Now. We can measure the energy 165 00:10:53,280 --> 00:10:56,400 Speaker 1: content of various fuels by using an apparatus that allows 166 00:10:56,440 --> 00:11:00,240 Speaker 1: the fuel to burn under what's called standard conditions. Sanery 167 00:11:00,280 --> 00:11:04,920 Speaker 1: conditions means zero degrees celsius and one bar of atmospheric pressure. 168 00:11:05,400 --> 00:11:08,360 Speaker 1: One bar is close to one atmosphere at sea level, 169 00:11:08,400 --> 00:11:11,280 Speaker 1: it's actually a little less. A container of water with 170 00:11:11,400 --> 00:11:15,680 Speaker 1: a known starting temperature and a known mass will absorb 171 00:11:15,760 --> 00:11:18,320 Speaker 1: the heat that's released from this reaction, so you burn 172 00:11:18,400 --> 00:11:21,960 Speaker 1: whatever the fuel is. The heat gets captured by a 173 00:11:22,120 --> 00:11:25,760 Speaker 1: known quantity of water that's at a known starting temperature. 174 00:11:26,280 --> 00:11:29,040 Speaker 1: You measure the change in temperature of the water, and 175 00:11:29,080 --> 00:11:31,280 Speaker 1: that can give you the amount of energy that was 176 00:11:31,360 --> 00:11:36,199 Speaker 1: released by this process. Dividing that by the mass of 177 00:11:36,240 --> 00:11:39,320 Speaker 1: the fuel that you burned will give you the energy 178 00:11:39,400 --> 00:11:43,720 Speaker 1: content of the fuel typically expressed in jewels program or 179 00:11:43,840 --> 00:11:48,000 Speaker 1: or more typically mega jewels per kilogram. This is called 180 00:11:48,320 --> 00:11:52,760 Speaker 1: the specific energy of the fuel. Natural gas, which is 181 00:11:52,800 --> 00:11:57,199 Speaker 1: mostly composed of methane, has a specific energy of fifty 182 00:11:57,280 --> 00:12:01,120 Speaker 1: five mega jewels per kilogram. Get selene has a specific 183 00:12:01,200 --> 00:12:05,440 Speaker 1: energy of forty six mega jewels per kilogram, so it's 184 00:12:05,480 --> 00:12:10,520 Speaker 1: not as energy dense in this respect as natural gases. 185 00:12:10,960 --> 00:12:14,880 Speaker 1: Coal has a specific energy of twenty four mega jewels 186 00:12:14,920 --> 00:12:18,400 Speaker 1: per kilogram. Wood is all the way down to sixteen 187 00:12:18,559 --> 00:12:23,479 Speaker 1: mega jewels per kilograms. So what about hydrogen. Well, hydrogen 188 00:12:23,520 --> 00:12:27,800 Speaker 1: packs a wallop at one hundred forty two mega jewels 189 00:12:27,840 --> 00:12:33,840 Speaker 1: per kilogram. But hydrogen is a gas, so a kilogram 190 00:12:33,840 --> 00:12:36,720 Speaker 1: of hydrogen, the lightest element, is going to be an 191 00:12:36,840 --> 00:12:41,319 Speaker 1: enormous volume of gas. The mass is the same, a 192 00:12:41,400 --> 00:12:44,040 Speaker 1: kilogram is a kilogram, but the volume the amount of 193 00:12:44,080 --> 00:12:48,000 Speaker 1: space it takes up, is different. So this is deceptive. 194 00:12:48,559 --> 00:12:52,200 Speaker 1: We can't just talk about hydrogen the least massive element, 195 00:12:52,320 --> 00:12:55,000 Speaker 1: in terms of mass. It makes more sense from a 196 00:12:55,080 --> 00:12:58,600 Speaker 1: practical perspective to talk about in terms of volume, because 197 00:12:58,640 --> 00:13:01,000 Speaker 1: that's how we're going to handle it. How much energy 198 00:13:01,200 --> 00:13:04,160 Speaker 1: is stored in hydrogen for a given unit of volume, 199 00:13:04,760 --> 00:13:07,200 Speaker 1: I'll tell you in just a second, but first let's 200 00:13:07,240 --> 00:13:18,280 Speaker 1: take a quick break to thank our sponsor. Okay, So 201 00:13:18,520 --> 00:13:22,120 Speaker 1: for practical purposes of using energy storage, we should really 202 00:13:22,160 --> 00:13:25,480 Speaker 1: look at how much energy hydrogen has per unit of volume, 203 00:13:25,800 --> 00:13:28,920 Speaker 1: not unit of mass. This is truly what we mean 204 00:13:29,000 --> 00:13:33,360 Speaker 1: by energy density. So gasoline has an energy density of 205 00:13:33,600 --> 00:13:38,280 Speaker 1: thirty four point to mega jewels per leader. Natural gas 206 00:13:38,520 --> 00:13:41,800 Speaker 1: has an energy density of twenty two point to mega 207 00:13:41,880 --> 00:13:45,160 Speaker 1: jewels per leader. So we see the gasoline comes out 208 00:13:45,160 --> 00:13:49,120 Speaker 1: ahead when we look at it by volume, not by mass. 209 00:13:49,480 --> 00:13:52,480 Speaker 1: But what of hydrogen. Well, if you compress it so 210 00:13:52,559 --> 00:13:55,480 Speaker 1: that you can put it in hydrogen tanks, you're looking 211 00:13:55,520 --> 00:13:59,880 Speaker 1: at an energy density of about nine mega jules per leader. 212 00:14:00,200 --> 00:14:04,080 Speaker 1: So you need more leaders of hydrogen than of gasoline 213 00:14:04,080 --> 00:14:06,480 Speaker 1: in order to do the same amount of work when 214 00:14:06,520 --> 00:14:10,079 Speaker 1: you're burning it as fuel. In other words, because gasoline 215 00:14:10,120 --> 00:14:12,760 Speaker 1: has the energy density of thirty four point two mega 216 00:14:12,800 --> 00:14:18,760 Speaker 1: jewels per leader, hydrogen at nine, so that's an issue. Still, 217 00:14:19,160 --> 00:14:23,040 Speaker 1: hydrogen would burn clean compared to fossil fuels, so we 218 00:14:23,080 --> 00:14:27,240 Speaker 1: would just need to have enough hydrogen to compensate for this. 219 00:14:27,600 --> 00:14:31,160 Speaker 1: So how hard is it to get pure hydrogen from 220 00:14:31,240 --> 00:14:36,040 Speaker 1: various sources and how do we typically produce hydrogen gas? Well, 221 00:14:36,160 --> 00:14:42,760 Speaker 1: right now of hydrogen production comes from wood or fossil fuels, 222 00:14:42,960 --> 00:14:47,680 Speaker 1: and the most common process is called natural gas reforming 223 00:14:48,080 --> 00:14:52,880 Speaker 1: or steam methane reforming. This involves exposing methane gas, that 224 00:14:53,280 --> 00:14:57,560 Speaker 1: carbon with four hydrogen atoms connected to it, two very 225 00:14:57,640 --> 00:15:00,680 Speaker 1: high temperature steam this cause. This is a couple of 226 00:15:00,720 --> 00:15:04,640 Speaker 1: successive chemical reactions, and the end result is you get 227 00:15:04,880 --> 00:15:10,200 Speaker 1: hydrogen gas and carbon dioxide. This, as you might imagine, 228 00:15:10,600 --> 00:15:14,080 Speaker 1: is a problem because carbon dioxide is a greenhouse gas, 229 00:15:14,320 --> 00:15:19,600 Speaker 1: and so is methane actually, and this process creates one 230 00:15:20,040 --> 00:15:22,880 Speaker 1: and makes use of the other. So while you could 231 00:15:23,000 --> 00:15:27,000 Speaker 1: burn the hydrogen gas and not create any carbon dioxide, 232 00:15:27,040 --> 00:15:30,880 Speaker 1: the actual process of producing the hydrogen gas using this 233 00:15:30,960 --> 00:15:35,280 Speaker 1: method releases CEO two. So this is a good reminder 234 00:15:35,720 --> 00:15:38,640 Speaker 1: that when we talk about alternatives to fossil fuels, we 235 00:15:38,680 --> 00:15:41,040 Speaker 1: actually have to look at a very big picture, not 236 00:15:41,200 --> 00:15:44,360 Speaker 1: just what happens when we burn the alternative, but how 237 00:15:44,400 --> 00:15:48,400 Speaker 1: do we produce the alternative does that in turn create 238 00:15:48,440 --> 00:15:51,040 Speaker 1: more greenhouse gases? We have to look at the whole 239 00:15:51,120 --> 00:15:53,960 Speaker 1: chain to make sure we're minimizing the emission of greenhouse 240 00:15:54,000 --> 00:15:57,960 Speaker 1: gases and the release of potentially hazardous materials. You can 241 00:15:58,000 --> 00:16:01,840 Speaker 1: produce hydrogen safely this way, and even in an environmentally 242 00:16:01,880 --> 00:16:05,200 Speaker 1: friendly way. If you can capture the carbon dioxide, if 243 00:16:05,240 --> 00:16:08,080 Speaker 1: you have a method of carbon capture and you're able 244 00:16:08,120 --> 00:16:10,720 Speaker 1: to capture the CEO two that's being given off by 245 00:16:10,720 --> 00:16:14,600 Speaker 1: this reaction, then that might be a good way to 246 00:16:14,680 --> 00:16:19,800 Speaker 1: produce hydrogen. However, adding those components, like the carbon capture components, 247 00:16:20,240 --> 00:16:23,600 Speaker 1: increases the expense of producing the hydrogen. It's it's more 248 00:16:23,600 --> 00:16:26,680 Speaker 1: expensive to do it that way, and as you add 249 00:16:26,680 --> 00:16:29,280 Speaker 1: in the cost of producing the hydrogen, it means that 250 00:16:29,320 --> 00:16:31,640 Speaker 1: you're going to have to sell the hydrogen for higher 251 00:16:31,720 --> 00:16:36,280 Speaker 1: costs to recapture that and economics plays a very important 252 00:16:36,360 --> 00:16:39,360 Speaker 1: part of this proposed hydrogen economy. If it is not 253 00:16:39,520 --> 00:16:43,480 Speaker 1: cost efficient, it is a very hard sell. Money is 254 00:16:43,520 --> 00:16:45,640 Speaker 1: another part of the puzzle that we have to manage. 255 00:16:46,480 --> 00:16:49,080 Speaker 1: We have to be careful about that. So if it 256 00:16:49,080 --> 00:16:52,920 Speaker 1: comes out that fossil fuels are significantly cheaper to produce 257 00:16:53,080 --> 00:16:56,600 Speaker 1: and use than hydrogen, it's really hard to get momentum 258 00:16:56,800 --> 00:17:00,680 Speaker 1: to switch from fossil fuels to hydrogen. If fossil fuels 259 00:17:00,720 --> 00:17:05,000 Speaker 1: become scarce and therefore become more expensive, or the production 260 00:17:05,040 --> 00:17:09,280 Speaker 1: of hydrogen becomes cheaper, then that could provide the economic 261 00:17:09,320 --> 00:17:13,400 Speaker 1: incentive to make the switch. Or if the environmental impacts 262 00:17:13,440 --> 00:17:16,600 Speaker 1: of using fossil fuels, we're creating expenses that were out 263 00:17:16,640 --> 00:17:18,760 Speaker 1: of control. If it were a point where we said 264 00:17:19,080 --> 00:17:22,040 Speaker 1: we have to switch from fossil fuels because dealing with 265 00:17:22,080 --> 00:17:26,840 Speaker 1: the consequences of fossil fuel use is getting too expensive, 266 00:17:27,440 --> 00:17:29,159 Speaker 1: then we might see a switch as well, but it 267 00:17:29,160 --> 00:17:31,520 Speaker 1: would probably be a little late for that. There are 268 00:17:31,640 --> 00:17:36,200 Speaker 1: methods of producing hydrogen that don't rely on this approach. 269 00:17:36,560 --> 00:17:38,639 Speaker 1: So one of them is that you could take charcoal. 270 00:17:38,800 --> 00:17:41,959 Speaker 1: Charcoal is when you really break it down, mostly carbon 271 00:17:42,040 --> 00:17:44,280 Speaker 1: and water when you get down to it. So you 272 00:17:44,320 --> 00:17:47,639 Speaker 1: can put charcoal in a very high temperature reactor and 273 00:17:47,680 --> 00:17:51,160 Speaker 1: burn charcoal at a temperature between twelve hundred and fifteen 274 00:17:51,240 --> 00:17:55,639 Speaker 1: hundred degrees celsius. Doing so well, it will release gas 275 00:17:56,000 --> 00:17:59,040 Speaker 1: and that gas will separate out and then reform into 276 00:17:59,119 --> 00:18:05,080 Speaker 1: hydrogen carbon monoxide. So yeah, hydrogen, but carbon monoxide is 277 00:18:05,119 --> 00:18:09,119 Speaker 1: toxic to many animals, including us, and it also plays 278 00:18:09,119 --> 00:18:12,639 Speaker 1: a part in the formation of smog. So that's not great. 279 00:18:13,000 --> 00:18:14,520 Speaker 1: I guess the one positive thing I could say is 280 00:18:14,560 --> 00:18:18,120 Speaker 1: carbon monoxide itself is not a greenhouse gas on its own. 281 00:18:18,640 --> 00:18:21,199 Speaker 1: But the way that the article I first mentioned at 282 00:18:21,240 --> 00:18:24,280 Speaker 1: the top of this episode is really focusing on is 283 00:18:24,320 --> 00:18:27,320 Speaker 1: a third method to produce hydrogen. It is one that 284 00:18:27,400 --> 00:18:31,080 Speaker 1: only produces oxygen and hydrogen. Those are the only two byproducts. 285 00:18:31,560 --> 00:18:35,879 Speaker 1: It is the process of electrolysis of water, and electrolysis 286 00:18:35,920 --> 00:18:39,960 Speaker 1: refers to the separation of bonded elements and compounds through 287 00:18:39,960 --> 00:18:43,280 Speaker 1: the use of an electric current. So the idea is, 288 00:18:43,320 --> 00:18:46,640 Speaker 1: if you pass an electric current of sufficient strength through 289 00:18:46,680 --> 00:18:50,479 Speaker 1: certain materials, you can break the molecular bonds holding the 290 00:18:50,520 --> 00:18:54,480 Speaker 1: atoms of that material together. Pure water, as it turns out, 291 00:18:55,280 --> 00:18:58,080 Speaker 1: isn't great for this. You would need a very very 292 00:18:58,119 --> 00:19:02,399 Speaker 1: strong current because pure water is a poor conductor of electricity. 293 00:19:02,640 --> 00:19:05,720 Speaker 1: What you need are electrolytes in the water. And I'm 294 00:19:05,760 --> 00:19:09,359 Speaker 1: not talking about the stuff that plants crave. I'm talking 295 00:19:09,359 --> 00:19:11,520 Speaker 1: about the substance that when you put it in water, 296 00:19:11,880 --> 00:19:16,840 Speaker 1: creates an electrically conducting solution. It introduces ions. In other words, 297 00:19:17,119 --> 00:19:19,439 Speaker 1: but you need to make sure that whatever electrolyte you 298 00:19:19,480 --> 00:19:24,960 Speaker 1: include in the mixture doesn't electrolyze more easily than water does, 299 00:19:25,520 --> 00:19:28,120 Speaker 1: because otherwise, what will happen is you put the electric 300 00:19:28,160 --> 00:19:32,520 Speaker 1: current into the solution and the electrolytes will electrolyze, whereas 301 00:19:32,560 --> 00:19:36,159 Speaker 1: the water will not, and you won't release hydrogen until 302 00:19:36,240 --> 00:19:38,359 Speaker 1: you just have pure water again, and you're back to 303 00:19:38,359 --> 00:19:42,600 Speaker 1: where you started. So one of the ions that is 304 00:19:42,600 --> 00:19:47,440 Speaker 1: frequently used for electrolysis would be sulfate ions, because sulfate 305 00:19:47,480 --> 00:19:51,440 Speaker 1: doesn't electrolyze more easily than water does. So you've got 306 00:19:51,440 --> 00:19:54,679 Speaker 1: your water and you've got your electrolytes in it, and 307 00:19:54,720 --> 00:19:57,399 Speaker 1: then you put two electrodes, and one of them is 308 00:19:57,400 --> 00:20:00,439 Speaker 1: connected to the negative terminal of the battery. One of 309 00:20:00,480 --> 00:20:02,879 Speaker 1: them is connected to the positive terminal of a battery. 310 00:20:02,920 --> 00:20:05,560 Speaker 1: I'm just using a battery for this particular example. It 311 00:20:05,600 --> 00:20:08,119 Speaker 1: doesn't have to be a battery. So you've got your 312 00:20:08,160 --> 00:20:11,359 Speaker 1: negatively charged electrode that's called the cathode, and you've got 313 00:20:11,440 --> 00:20:15,000 Speaker 1: your positively charged electrode that's called the anode, and you 314 00:20:15,040 --> 00:20:18,200 Speaker 1: insert them in the water. Now, what will happen, assuming 315 00:20:18,240 --> 00:20:21,679 Speaker 1: you've done this correctly, is that hydrogen gas will bubble 316 00:20:21,800 --> 00:20:25,399 Speaker 1: up around the cathode, and oxygen will bubble up around 317 00:20:25,440 --> 00:20:30,040 Speaker 1: the anode. One of the traditional challenges associated with electrolysis 318 00:20:30,080 --> 00:20:33,080 Speaker 1: of water on a large scale is that the electro 319 00:20:33,280 --> 00:20:39,280 Speaker 1: catalysts catalysts are things that facilitate the reactions and chemical reactions. 320 00:20:39,280 --> 00:20:43,359 Speaker 1: They make chemical reactions happen more easily or with less 321 00:20:43,480 --> 00:20:47,400 Speaker 1: energy if you prefer. The electrode. Catalysts that we tend 322 00:20:47,400 --> 00:20:50,600 Speaker 1: to use for electrolysis also tend to be pretty rare 323 00:20:50,760 --> 00:20:54,520 Speaker 1: and expensive. Like one of the common ones is platinum, 324 00:20:54,680 --> 00:20:57,480 Speaker 1: but platinum is not easy to get. It is rare, 325 00:20:57,960 --> 00:21:00,800 Speaker 1: and so it's very costly, and that means the cost 326 00:21:00,840 --> 00:21:03,680 Speaker 1: of building out the system to produce hydrogen will get 327 00:21:03,760 --> 00:21:06,800 Speaker 1: driven up. And as I already mentioned, cost is one 328 00:21:06,800 --> 00:21:09,520 Speaker 1: of those factors we can't just ignore when it comes 329 00:21:09,560 --> 00:21:14,840 Speaker 1: to creating an alternative fossil fuels. So in some scientists 330 00:21:14,880 --> 00:21:17,639 Speaker 1: at the University of Houston announced the development of a 331 00:21:17,680 --> 00:21:22,280 Speaker 1: new electro catalyst made from a conductive nickel foam material 332 00:21:22,440 --> 00:21:26,200 Speaker 1: and a ferris metaphosphate. The relevant point here is that 333 00:21:26,680 --> 00:21:30,320 Speaker 1: this stuff costs less to make than if you were 334 00:21:30,359 --> 00:21:32,679 Speaker 1: to go out and get platinum. So this is a 335 00:21:32,720 --> 00:21:36,720 Speaker 1: push to make hydrogen production economically viable. And like I 336 00:21:36,720 --> 00:21:39,720 Speaker 1: said before, you have to take this big picture into account. 337 00:21:40,119 --> 00:21:43,159 Speaker 1: So that doesn't just include the materials you need to 338 00:21:43,160 --> 00:21:46,359 Speaker 1: perform electrolysis on water. You also have to ask where 339 00:21:46,480 --> 00:21:50,119 Speaker 1: is the electricity coming from? What is providing the electricity 340 00:21:50,160 --> 00:21:53,720 Speaker 1: I'm using for electrolysis. If you trace back the source 341 00:21:53,760 --> 00:21:56,720 Speaker 1: of your electricity and ultimately you're drawing electricity from a 342 00:21:56,800 --> 00:22:02,600 Speaker 1: coal firing power plant, then you haven't really solved any problems. 343 00:22:03,320 --> 00:22:06,440 Speaker 1: The pollution is still in the equation. It's just over 344 00:22:06,560 --> 00:22:10,399 Speaker 1: in the electricity production side as opposed to the direct 345 00:22:10,520 --> 00:22:14,560 Speaker 1: hydrogen production side. In fact, depending upon your approach, you 346 00:22:14,600 --> 00:22:17,679 Speaker 1: may be consuming more fuel and using up more stored 347 00:22:17,800 --> 00:22:20,840 Speaker 1: energy than you are producing by creating hydrogen if you 348 00:22:20,880 --> 00:22:23,439 Speaker 1: have a very inefficient system, and you'd be using a 349 00:22:23,480 --> 00:22:26,400 Speaker 1: process that releases greenhouse gases to boot, so that would 350 00:22:26,440 --> 00:22:31,360 Speaker 1: be a really bad idea. The article talked about green hydrogen, 351 00:22:31,400 --> 00:22:34,639 Speaker 1: and by that they meant using some sort of renewable 352 00:22:34,760 --> 00:22:38,480 Speaker 1: energy source to create the electricity, such as wind power 353 00:22:38,600 --> 00:22:41,119 Speaker 1: or solar power. That can be a step in the 354 00:22:41,200 --> 00:22:44,639 Speaker 1: right direction. If you're using wind power, solar power hydro 355 00:22:44,720 --> 00:22:48,080 Speaker 1: power or whatever, and you're generating more electricity then you 356 00:22:48,160 --> 00:22:52,240 Speaker 1: need to supply given area at a given time. Then 357 00:22:52,240 --> 00:22:54,480 Speaker 1: if you were to pair those facilities with an electric 358 00:22:54,760 --> 00:22:59,440 Speaker 1: electrolyzer facility, electrolysis facility, if you if you will, that 359 00:22:59,480 --> 00:23:02,800 Speaker 1: would make a of sense because electricity is a use it, 360 00:23:03,200 --> 00:23:07,040 Speaker 1: store it, or lose it commodity. At some point, you 361 00:23:07,119 --> 00:23:10,600 Speaker 1: might be producing more electricity than you need at that time, 362 00:23:10,880 --> 00:23:13,119 Speaker 1: and rather than lose it, you can put it to work. 363 00:23:13,240 --> 00:23:15,919 Speaker 1: You can take that excess electricity and put it to 364 00:23:15,920 --> 00:23:19,280 Speaker 1: work to produce hydrogen. So that article I mentioned at 365 00:23:19,320 --> 00:23:22,840 Speaker 1: the beginning of this episode goes into this concept in particular, 366 00:23:23,160 --> 00:23:27,000 Speaker 1: and it talks about a project in Len's Austria. That 367 00:23:27,040 --> 00:23:30,399 Speaker 1: project is called H two future H two, referring to 368 00:23:30,480 --> 00:23:34,440 Speaker 1: hydrogen gas. The goal is not just to create hydrogen 369 00:23:34,520 --> 00:23:38,800 Speaker 1: gas using electricity from renewable energy sources, but to use 370 00:23:38,800 --> 00:23:41,600 Speaker 1: the hydrogen as a fuel source for steel production. It 371 00:23:41,640 --> 00:23:45,479 Speaker 1: would be co located with a steel production plant, so 372 00:23:45,520 --> 00:23:50,159 Speaker 1: this would create green steel and steel production usually requires 373 00:23:50,200 --> 00:23:53,320 Speaker 1: burning a lot of coal and uh. It turns out 374 00:23:53,359 --> 00:23:57,240 Speaker 1: that steel and cement production together are responsible for about 375 00:23:57,320 --> 00:24:01,600 Speaker 1: twenty percent of all carbon diet side emissions in the world, 376 00:24:01,680 --> 00:24:04,760 Speaker 1: So if you could bring that down by creating a 377 00:24:04,840 --> 00:24:10,199 Speaker 1: hydrogen based steel production plant, you could drastically reduce the 378 00:24:10,200 --> 00:24:14,359 Speaker 1: amount of carbon dioxide that's being emitted into the atmosphere. 379 00:24:14,960 --> 00:24:17,800 Speaker 1: I'll talk more about these plans in just a second, 380 00:24:17,840 --> 00:24:20,920 Speaker 1: but first let's take another quick break to thank our sponsor. 381 00:24:28,520 --> 00:24:31,879 Speaker 1: The H two future project is a small scale test. 382 00:24:32,040 --> 00:24:35,280 Speaker 1: So this electrolyzer is paired with that steel plant, and 383 00:24:35,320 --> 00:24:38,199 Speaker 1: it's going to run at a capacity of six megawatts, 384 00:24:38,280 --> 00:24:41,920 Speaker 1: which is not particularly powerful in the grand scheme of things. 385 00:24:42,400 --> 00:24:44,640 Speaker 1: According to the article I was reading, which is over 386 00:24:44,680 --> 00:24:47,880 Speaker 1: on fizz dot org p h y s dot org, 387 00:24:48,320 --> 00:24:52,160 Speaker 1: this will result in the production of twelve cubic meters 388 00:24:52,200 --> 00:24:55,639 Speaker 1: of hydrogen per hour, and if the test proves promising, 389 00:24:56,080 --> 00:24:59,440 Speaker 1: the plant could invest in building a much larger electrolyzer 390 00:24:59,480 --> 00:25:03,000 Speaker 1: that could offer rate at a capacity of one hundred megawatts, 391 00:25:03,000 --> 00:25:07,720 Speaker 1: significantly more powerful than six megawatts. The article also mentions 392 00:25:07,760 --> 00:25:11,720 Speaker 1: a similar project in Cologne, Germany called Refine, but it's 393 00:25:11,960 --> 00:25:15,320 Speaker 1: r E f h y n E. It is a 394 00:25:15,359 --> 00:25:19,920 Speaker 1: ten megawatt electroalizer that's co located with an existing hydrogen 395 00:25:20,000 --> 00:25:23,639 Speaker 1: refinery that's been using the steam reforming method to produce 396 00:25:23,760 --> 00:25:27,440 Speaker 1: hydrogen up to that point. Like the H two Future project, 397 00:25:27,600 --> 00:25:29,879 Speaker 1: this is a test, it's a pilot program. It's not 398 00:25:29,920 --> 00:25:33,320 Speaker 1: going to produce nearly as much hydrogen as the steam 399 00:25:33,400 --> 00:25:37,040 Speaker 1: reforming process at this level of power. It comes down 400 00:25:37,080 --> 00:25:40,119 Speaker 1: to about a hundred eighty thousand tons from the steam 401 00:25:40,200 --> 00:25:46,439 Speaker 1: reform process versus hundred tons from electrolysis. But again, this technology, 402 00:25:46,720 --> 00:25:50,199 Speaker 1: if it works, could be scaled up and then you 403 00:25:50,240 --> 00:25:53,800 Speaker 1: would see more and more hydrogen being produced through electrolysis 404 00:25:53,840 --> 00:25:57,280 Speaker 1: and less through the steam reforming process. Now I focused 405 00:25:57,520 --> 00:26:00,800 Speaker 1: mainly on hydrogen production, but that's still just one piece 406 00:26:01,000 --> 00:26:05,320 Speaker 1: of making a viable hydrogen economy. It's a super important one, obviously, 407 00:26:05,359 --> 00:26:07,639 Speaker 1: because if you don't have hydrogen, then the rest of 408 00:26:07,680 --> 00:26:09,760 Speaker 1: it doesn't make any sense at all. But even if 409 00:26:09,800 --> 00:26:12,840 Speaker 1: we were able to make plenty of hydrogen, let's say 410 00:26:12,840 --> 00:26:14,959 Speaker 1: that we've solved that problem. We've come up with an 411 00:26:15,000 --> 00:26:19,399 Speaker 1: electrolysis approach that uses green energy, it's incredibly efficient, and 412 00:26:19,440 --> 00:26:22,919 Speaker 1: now we're just churning out hydrogen like crazy. We still 413 00:26:22,960 --> 00:26:26,200 Speaker 1: have some other challenges. For one thing, we've got designed 414 00:26:26,240 --> 00:26:29,720 Speaker 1: stuff to store the hydrogen and we have hydrogen tanks, 415 00:26:29,720 --> 00:26:31,080 Speaker 1: but we would need to build a lot of them 416 00:26:31,119 --> 00:26:35,840 Speaker 1: and to UH to test the various designs out, we 417 00:26:35,880 --> 00:26:38,920 Speaker 1: would have to design stuff to run on the hydrogen. 418 00:26:39,680 --> 00:26:42,960 Speaker 1: So what are our options here, Well, first, you could 419 00:26:43,119 --> 00:26:48,480 Speaker 1: burn hydrogen fuel like gasoline. There are hydrogen internal combustion engines, 420 00:26:48,560 --> 00:26:51,280 Speaker 1: for example, and you would refuel them in a way 421 00:26:51,359 --> 00:26:55,000 Speaker 1: very similar that the way you refuel a gasoline powered engine. 422 00:26:55,720 --> 00:26:59,119 Speaker 1: So there are vehicles that use this UH in the 423 00:26:59,160 --> 00:27:02,800 Speaker 1: exact same way it cars use gas or petrol. Or 424 00:27:03,160 --> 00:27:06,520 Speaker 1: you could use fuel cells, which in a way is 425 00:27:06,640 --> 00:27:10,960 Speaker 1: essentially that electrolysis process, but in reverse. So with a 426 00:27:11,000 --> 00:27:14,080 Speaker 1: fuel cell, hydrogen based fuel cell. I should add there 427 00:27:14,119 --> 00:27:16,880 Speaker 1: are different types of fuel cells, but we're specifically talking 428 00:27:16,880 --> 00:27:20,960 Speaker 1: about the hydrogen based ones. You on a very basic level, 429 00:27:21,080 --> 00:27:23,879 Speaker 1: you have hydrogen and a fuel cell on one side 430 00:27:23,880 --> 00:27:27,240 Speaker 1: of the cell. You have oxygen on the other side 431 00:27:27,280 --> 00:27:29,959 Speaker 1: of the cell, and between these two gases you have 432 00:27:29,960 --> 00:27:33,359 Speaker 1: a special membrane with a catalyst on it, and the 433 00:27:33,440 --> 00:27:36,919 Speaker 1: hydrogen passes through the membrane, but the membrane requires the 434 00:27:36,960 --> 00:27:39,879 Speaker 1: hydrogen to ditch an electron. First. It says, all right, 435 00:27:39,920 --> 00:27:42,040 Speaker 1: you can come through, but your friend can't. So the 436 00:27:42,080 --> 00:27:46,280 Speaker 1: electrons like ah. But the electron really doesn't want to 437 00:27:46,320 --> 00:27:48,000 Speaker 1: be with a bunch of other electrons. There are a 438 00:27:48,040 --> 00:27:51,440 Speaker 1: bunch of negative dancings, and we all know that similar 439 00:27:51,560 --> 00:27:55,040 Speaker 1: charges repel each other. So you have more and more 440 00:27:55,080 --> 00:27:57,400 Speaker 1: electrons building up. They do not want to be with 441 00:27:57,440 --> 00:28:00,560 Speaker 1: each other. You provide a pathway for those electrons to 442 00:28:00,640 --> 00:28:03,520 Speaker 1: follow a circuit. In other words, you make them do 443 00:28:03,680 --> 00:28:07,840 Speaker 1: work along this circuit, and eventually the electrons are allowed 444 00:28:07,880 --> 00:28:11,760 Speaker 1: to rejoin the hydrogen nuclei, which again are just protons. 445 00:28:11,800 --> 00:28:14,920 Speaker 1: Remember that are on the other side, and that also 446 00:28:15,000 --> 00:28:18,720 Speaker 1: combines with the oxygen and you end up creating water 447 00:28:18,960 --> 00:28:21,920 Speaker 1: as a result. So you get electricity, water and heat. 448 00:28:22,200 --> 00:28:26,040 Speaker 1: That's the only thing the fuel cell gives off. Hydrogen. 449 00:28:26,080 --> 00:28:30,000 Speaker 1: Internal combustion engines aren't really that much different from standard 450 00:28:30,119 --> 00:28:34,680 Speaker 1: combustion engines. They require some modifications, like you wouldn't want 451 00:28:34,680 --> 00:28:37,560 Speaker 1: to have spark plugs that have platinum tips, for example, 452 00:28:37,600 --> 00:28:40,560 Speaker 1: because that would react with the hydrogen. You want special 453 00:28:40,600 --> 00:28:44,360 Speaker 1: fuel injectors, special valves. You also would need a specialized 454 00:28:44,440 --> 00:28:48,760 Speaker 1: hydrogen storage system otherwise known as a hydrogen tank. The 455 00:28:48,760 --> 00:28:51,640 Speaker 1: combustion chamber would also need to be optimized to really 456 00:28:51,680 --> 00:28:54,600 Speaker 1: harness the most energy out of combusting the hydrogen because 457 00:28:54,640 --> 00:28:59,680 Speaker 1: remember hydrogen, uh, the energy density is lower than that 458 00:28:59,800 --> 00:29:02,880 Speaker 1: of gasoline, so you need to really optimize the engine 459 00:29:02,920 --> 00:29:05,480 Speaker 1: to take advantage of all that power as much as 460 00:29:05,480 --> 00:29:08,120 Speaker 1: it can to make it as efficient as possible. Hydrogen 461 00:29:08,160 --> 00:29:10,680 Speaker 1: burns way more readily than other fuels, so it also 462 00:29:10,720 --> 00:29:15,080 Speaker 1: burns faster. The big advantage of this approach over fuel 463 00:29:15,080 --> 00:29:17,320 Speaker 1: cells is that a lot of the work has already 464 00:29:17,360 --> 00:29:20,600 Speaker 1: been done, which means making vehicles that run on hydrogen 465 00:29:20,760 --> 00:29:24,800 Speaker 1: as a combustible fuel is relatively inexpensive. A lot of 466 00:29:24,840 --> 00:29:27,920 Speaker 1: the work has already been done in that field. But 467 00:29:28,520 --> 00:29:31,720 Speaker 1: burning hydrogen in a combustion chamber is not the same 468 00:29:31,760 --> 00:29:34,360 Speaker 1: thing as burning it with pure oxygen. It means combining 469 00:29:34,360 --> 00:29:37,680 Speaker 1: it with atmospheric air, and that also means that there's 470 00:29:37,720 --> 00:29:41,280 Speaker 1: nitrogen in the air and you will eventually start producing 471 00:29:41,360 --> 00:29:44,920 Speaker 1: nitrogen oxides as a byproduct. Now, it's a much smaller 472 00:29:44,960 --> 00:29:48,560 Speaker 1: amount of nitrogen oxides than you would typically typically get 473 00:29:48,600 --> 00:29:51,720 Speaker 1: with a gasoline or diesel powered engine, but it still 474 00:29:51,720 --> 00:29:56,000 Speaker 1: means that the hydrogen combustion engine cars are not pollution free. 475 00:29:56,080 --> 00:29:59,560 Speaker 1: And because we need to look at the volumetric energy 476 00:29:59,640 --> 00:30:02,760 Speaker 1: density of hydrogen. Those engines produce less power than a 477 00:30:02,800 --> 00:30:06,920 Speaker 1: comparable gasoline engine. Fuel cell vehicles get a bit more 478 00:30:06,960 --> 00:30:09,720 Speaker 1: omph out of a similar amount of hydrogen than the 479 00:30:09,840 --> 00:30:12,440 Speaker 1: hydrogen combustion engines do. Actually they get a lot more. 480 00:30:13,040 --> 00:30:15,920 Speaker 1: Fuel cells can be pretty efficient, like around the seventy 481 00:30:15,920 --> 00:30:20,000 Speaker 1: percentile range. They produce electricity, so you would pair these 482 00:30:20,040 --> 00:30:22,880 Speaker 1: fuel cells with an electric motor, and in many ways, 483 00:30:22,920 --> 00:30:26,600 Speaker 1: fuel cell vehicles and electric vehicles are very similar. It's 484 00:30:26,640 --> 00:30:29,720 Speaker 1: just that electric vehicles run on batteries that have to 485 00:30:29,760 --> 00:30:35,000 Speaker 1: be recharged. Fuel cells rely on fuel. It's in the name, 486 00:30:35,120 --> 00:30:37,240 Speaker 1: so you have to refuel the fuel cell rather than 487 00:30:37,280 --> 00:30:41,160 Speaker 1: recharge it. Obviously, vehicles would just be one potential use 488 00:30:41,240 --> 00:30:43,360 Speaker 1: for hydrogen. It could be used as a fuel in 489 00:30:43,480 --> 00:30:47,280 Speaker 1: tons of different applications. But there's still other problems that 490 00:30:47,320 --> 00:30:50,200 Speaker 1: we would have to solve. A big one is infrastructure. 491 00:30:50,240 --> 00:30:53,720 Speaker 1: It took decades to build out the infrastructure we've got 492 00:30:53,720 --> 00:30:56,440 Speaker 1: for fossil fuels, and that infrastructure has grown over the 493 00:30:56,480 --> 00:31:00,400 Speaker 1: course of more than a century. It's an estable, published 494 00:31:00,520 --> 00:31:04,280 Speaker 1: and entrenched system. In many ways, it's an investment. In 495 00:31:04,320 --> 00:31:06,320 Speaker 1: other words, so we would have to build out something 496 00:31:06,360 --> 00:31:08,880 Speaker 1: similar for hydrogen if we were to depend upon that 497 00:31:08,920 --> 00:31:12,160 Speaker 1: more heavily as an energy storage method, so that would 498 00:31:12,200 --> 00:31:16,520 Speaker 1: be a really big price tag. Also, revisiting the production 499 00:31:16,560 --> 00:31:18,840 Speaker 1: issue for just a moment, there's the question of where 500 00:31:18,880 --> 00:31:21,320 Speaker 1: do you get the water. If you're relying on the 501 00:31:21,360 --> 00:31:25,800 Speaker 1: electrolysis method, preferably you would be using freshwater. It provides 502 00:31:25,920 --> 00:31:29,480 Speaker 1: fewer problems than salt water. But in some areas, fresh 503 00:31:29,520 --> 00:31:32,320 Speaker 1: water is a very precious commodity that's in short supply, 504 00:31:32,640 --> 00:31:35,480 Speaker 1: so it would make very little sense to switch to 505 00:31:35,760 --> 00:31:39,320 Speaker 1: water and have it become even more scarce by dedicating 506 00:31:39,360 --> 00:31:42,360 Speaker 1: a good portion of it towards energy. There are projects 507 00:31:42,600 --> 00:31:45,480 Speaker 1: that are experimenting with using sea water as a source 508 00:31:45,520 --> 00:31:48,280 Speaker 1: for hydrogen, but seawater has lots of other stuff in 509 00:31:48,320 --> 00:31:51,600 Speaker 1: it that can cause problems from this process, and it 510 00:31:51,720 --> 00:31:55,040 Speaker 1: may be small problems, like relatively small problems like corrosion 511 00:31:55,120 --> 00:31:57,440 Speaker 1: of the electrodes, which is, you know, it means you'd 512 00:31:57,440 --> 00:31:59,680 Speaker 1: have to replace the electrodes a much much more frequently 513 00:31:59,720 --> 00:32:02,280 Speaker 1: in the electoralizer. But there are other problems as well, 514 00:32:02,360 --> 00:32:05,800 Speaker 1: like the possibility that you would start producing chlorine gas, 515 00:32:05,920 --> 00:32:09,640 Speaker 1: which is deadly stuff. We've been talking about switching to 516 00:32:09,720 --> 00:32:13,760 Speaker 1: hydrogen as a primary energy storage solution for a really 517 00:32:13,800 --> 00:32:17,360 Speaker 1: long time. The term hydrogen economy, which describes a holistic 518 00:32:17,440 --> 00:32:20,600 Speaker 1: system of delivering energy through hydrogen, first popped on the 519 00:32:20,600 --> 00:32:23,640 Speaker 1: scene way back in nineteen seventy and I talked at 520 00:32:23,880 --> 00:32:28,960 Speaker 1: General Motors. A guy named Bernard Patrick John O'Meara Bachris, 521 00:32:29,280 --> 00:32:32,760 Speaker 1: or just John Bachris, came up with this phrase. Dr 522 00:32:32,800 --> 00:32:36,400 Speaker 1: Bachris was a chemistry professor and a proponent of hydrogen 523 00:32:36,440 --> 00:32:40,200 Speaker 1: for quite some time. This concept would see support come 524 00:32:40,240 --> 00:32:42,600 Speaker 1: and go over the years. Sometimes it would get a 525 00:32:42,640 --> 00:32:46,040 Speaker 1: little more focus, sometimes fade into the background. In addition 526 00:32:46,040 --> 00:32:49,000 Speaker 1: to the benefit that hydrogen would produce fewer pollutants than 527 00:32:49,040 --> 00:32:53,640 Speaker 1: fossil fuels, hydrogen economy would turn a country with water 528 00:32:53,760 --> 00:32:58,440 Speaker 1: access into a self sufficient nation from an energy standpoint, 529 00:32:58,520 --> 00:33:01,000 Speaker 1: which in turn would bolster now sational security because it 530 00:33:01,000 --> 00:33:03,880 Speaker 1: would mean the country wouldn't have to rely upon fossil 531 00:33:03,920 --> 00:33:07,800 Speaker 1: fuel resources that are produced in other countries. So in 532 00:33:07,840 --> 00:33:11,000 Speaker 1: the early two thousands, during the administration of George W. Bush, 533 00:33:11,200 --> 00:33:14,360 Speaker 1: the hydrogen economy got a lot of support, largely for 534 00:33:14,400 --> 00:33:17,520 Speaker 1: that reason it would remove our dependence upon foreign oil. 535 00:33:18,040 --> 00:33:21,600 Speaker 1: There are people who oppose the development of the hydrogen economy, 536 00:33:21,840 --> 00:33:24,200 Speaker 1: not saying it was a bad idea necessarily, but saying 537 00:33:24,400 --> 00:33:26,640 Speaker 1: it's going to end up being too costly and not 538 00:33:26,720 --> 00:33:29,840 Speaker 1: efficient enough to meet our needs, so it would at 539 00:33:29,880 --> 00:33:33,280 Speaker 1: best be distracting and at worst be completely wasteful and 540 00:33:33,280 --> 00:33:36,320 Speaker 1: and waste time and resources that could be spent on 541 00:33:36,480 --> 00:33:39,920 Speaker 1: different alternatives. And they may well have a point. It's 542 00:33:39,960 --> 00:33:42,640 Speaker 1: really hard to say right now, but hydrogen is likely 543 00:33:42,680 --> 00:33:45,920 Speaker 1: to be at least a component of alternate fuel and 544 00:33:46,040 --> 00:33:49,600 Speaker 1: energy solutions moving forward. It could end up being a 545 00:33:49,720 --> 00:33:53,200 Speaker 1: huge component if we get fusion to work, because fusion 546 00:33:53,240 --> 00:33:57,719 Speaker 1: would rely upon isotopes of hydrogen, and then you're talking 547 00:33:58,440 --> 00:34:03,560 Speaker 1: enormous energy density ease that more than dwarf the combustible 548 00:34:03,560 --> 00:34:07,080 Speaker 1: fuels we're talking about now. How big a part hydrogen 549 00:34:07,160 --> 00:34:09,560 Speaker 1: is going to play as a fuel remains to be seen. 550 00:34:09,719 --> 00:34:12,839 Speaker 1: It may require breakthroughs in both production and in how 551 00:34:12,880 --> 00:34:15,040 Speaker 1: we put it to use, and until we have a 552 00:34:15,080 --> 00:34:18,640 Speaker 1: storage and transportation infrastructure built out to support this, will 553 00:34:18,680 --> 00:34:21,080 Speaker 1: not be able to really rely upon it as extensively 554 00:34:21,120 --> 00:34:24,279 Speaker 1: as we do fossil fuels. So can we produce enough 555 00:34:24,360 --> 00:34:27,000 Speaker 1: hydrogen to meet our needs. I think the right answer 556 00:34:27,160 --> 00:34:30,520 Speaker 1: now is not yet, or maybe the answer is that's 557 00:34:30,600 --> 00:34:32,600 Speaker 1: just one part of the challenge, and we have to 558 00:34:32,640 --> 00:34:35,480 Speaker 1: solve a whole lot of problems to make hydrogen practical. 559 00:34:35,800 --> 00:34:38,759 Speaker 1: So let's not worry about too much. Let's try and 560 00:34:38,800 --> 00:34:41,640 Speaker 1: solve these problems first. Now, I do think it's worth pursuing. 561 00:34:41,680 --> 00:34:44,319 Speaker 1: I think fuel cells are super cool. I know some 562 00:34:44,360 --> 00:34:47,640 Speaker 1: people who love electric cars and that model, and they're 563 00:34:47,680 --> 00:34:50,600 Speaker 1: totally dismissive of fuel cells, But personally, I think both 564 00:34:50,680 --> 00:34:54,000 Speaker 1: models can work. And besides, even if we don't get 565 00:34:54,080 --> 00:34:57,200 Speaker 1: fuel cell vehicles rolled out on a wide scale, we 566 00:34:57,239 --> 00:35:00,640 Speaker 1: may put hydrogen to use in many other places. That 567 00:35:00,680 --> 00:35:03,400 Speaker 1: wraps up this episode. If you guys have suggestions for 568 00:35:03,480 --> 00:35:06,239 Speaker 1: future episodes of tech Stuff, you can visit the tech 569 00:35:06,320 --> 00:35:10,000 Speaker 1: Stuff podcast dot com website. There you will find ways 570 00:35:10,040 --> 00:35:12,399 Speaker 1: to contact me on Facebook or Twitter, or you can 571 00:35:12,440 --> 00:35:15,000 Speaker 1: email me. The address is tech Stuff at how stuff 572 00:35:15,000 --> 00:35:17,680 Speaker 1: works dot com. You can go visit our store that's 573 00:35:17,719 --> 00:35:20,440 Speaker 1: over at t public dot com slash tech Stuff. 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For more on this and 583 00:35:54,280 --> 00:36:00,000 Speaker 1: thousands of other topics, visit how staff works dot com. 584 00:36:00,360 --> 00:36:02,760 Speaker 1: Wom