0 1 00:00:04,580 --> 00:00:07,390 Let's start with the first question. 1 2 00:00:08,850 --> 00:00:10,610 What is energy. 2 3 00:00:11,700 --> 00:00:23,190 I noticed that when I ask this question to students they usually have a terrible giving an exact definition 3 4 00:00:24,030 --> 00:00:37,110 and I must say it is not easy so the scientific definition for energy would be like this, the capacity 4 5 00:00:37,260 --> 00:00:46,740 of the system to perform work. we humans use energy to do some work. 5 6 00:00:46,840 --> 00:00:52,050 We use energy for heating air and water. 6 7 00:00:52,150 --> 00:01:05,170 We use energy for transportation of people and products by cars, trains, trucks and even planes. 7 8 00:01:05,170 --> 00:01:11,620 We use energy to produce foods and products. 8 9 00:01:11,620 --> 00:01:17,910 We use energy to illuminate our houses and streets. 9 10 00:01:17,920 --> 00:01:29,770 We use energy to watch TV, do our laundry, working on computer and surfing internet at this moment. 10 11 00:01:29,890 --> 00:01:34,830 You are consuming energy by watching this. 11 12 00:01:34,940 --> 00:01:35,170 video 12 13 00:01:37,830 --> 00:01:50,780 energy appears in many forms in our daily life like gravitational energy or kinetic energy or even 13 14 00:01:51,140 --> 00:02:06,260 mechanical energy or electrical energy, heat radiation, wave energy, chemical energy and nuclear energy 14 15 00:02:10,770 --> 00:02:23,720 total amount of electrical energy is always conserved in the form of energy may be change in the time 15 16 00:02:24,260 --> 00:02:27,560 but the total amount doesn't change. 16 17 00:02:27,560 --> 00:02:38,330 This mean that if we want energy to work for us we usually convert it from one form to another form 17 18 00:02:38,330 --> 00:02:44,370 An example is the electrical motor. 18 19 00:02:44,370 --> 00:02:55,850 This is a tool in which we convert electrical energy into mechanical energy , the unit of energy is joule 19 20 00:02:57,990 --> 00:03:13,810 so that power is the energy per time and it expressed in watt one watt is one joule per second in our 20 21 00:03:13,810 --> 00:03:25,690 course we will use more practical unit which is generally used to express electrical energy which 21 22 00:03:25,690 --> 00:03:41,310 is kilowatt hour. one kilowatt hour equals to the electrical energy of power of kilowatt being used for 22 23 00:03:41,310 --> 00:03:45,910 one hour one kilowatt hour. 23 24 00:03:46,030 --> 00:03:50,460 equals 3.6 million joules 24 25 00:03:53,920 --> 00:04:02,460 the energy problem the world as we know today is based on the capability of humans to convert the 25 26 00:04:02,590 --> 00:04:06,710 energy from one form to another form 26 27 00:04:06,710 --> 00:04:19,210 Most technological developed nations are also the once which you have access to and are using the most 27 28 00:04:19,420 --> 00:04:21,280 energy per capita 28 29 00:04:23,690 --> 00:04:35,200 for many people believe that the biggest challenge for humankind in this century is tackling the energy 29 30 00:04:35,200 --> 00:04:39,540 problem why do we have a problem. 30 31 00:04:39,940 --> 00:04:51,700 the first challenge is that humankind is facing supply demand problem that demand is growing constantly. 31 32 00:04:52,060 --> 00:05:03,760 The world population is still rapidly growing and some studies predict world of population of 9 32 33 00:05:03,760 --> 00:05:13,980 billion around 2040 in reference to the 7 billion people living on this planet today. 33 34 00:05:15,140 --> 00:05:16,400 All this people. 34 35 00:05:16,460 --> 00:05:23,440 will need energy which increases the global energy demand. 35 36 00:05:23,450 --> 00:05:32,740 In addition the energy consumption per capita is linked to the living standards of the country. 36 37 00:05:34,210 --> 00:05:44,720 In 2010 in the same United State at around 230 kilowatt hour of energy per capita 37 38 00:05:45,200 --> 00:05:47,660 per day was used 38 39 00:05:52,410 --> 00:06:04,470 otherwise countries in Africa like Nigeria for example only use 1/10 of this energy at around 39 40 00:06:05,310 --> 00:06:11,670 23 kilowatt hour bad day per capita in this graph. 40 41 00:06:11,670 --> 00:06:22,360 You see the living standard expressed in human development index the darker color , the more developed region. 41 42 00:06:22,740 --> 00:06:29,000 However the light color in this figure is getting darker by. 42 43 00:06:29,100 --> 00:06:29,760 the years 43 44 00:06:34,130 --> 00:06:36,060 in many countries. 44 45 00:06:36,210 --> 00:06:48,180 the living standard is rapidly increasing like China and India where approximately 2.5 billion people 45 46 00:06:48,270 --> 00:06:49,760 already. 46 47 00:06:49,830 --> 00:06:55,980 These people represent more than a third of the world population. 47 48 00:06:56,070 --> 00:07:05,380 both increasing world population and increasing living standards will increase the energy 48 49 00:07:05,380 --> 00:07:19,510 demand the international energy outlook in 2013 predicts that energy consumption will increase by 56 49 50 00:07:19,800 --> 00:07:34,390 per cent by 2040 in reference to 2010. the increasing demand in energy has economic impact as well. 50 51 00:07:34,390 --> 00:07:44,190 If there is more demand for product while supply doesn't change much that product. 51 52 00:07:44,410 --> 00:07:46,300 will get more expensive 52 53 00:07:50,960 --> 00:08:01,010 as an example we show a plot of the annual average price for the oil and barrel normalize to the value 53 54 00:08:01,670 --> 00:08:05,200 in dollar. 54 55 00:08:05,240 --> 00:08:16,250 first, You can see that price went up during the oil crisis in the seventies in this decade. 55 56 00:08:16,250 --> 00:08:28,220 Some countries stopped producing and trading oil for while. the second era of higher oil pricing is started 56 57 00:08:28,340 --> 00:08:37,340 as the beginning of this millennium due to the increasing demand from you new growing economics the 57 58 00:08:37,370 --> 00:08:43,840 oil pricing had been sufficiently increased. 58 59 00:08:43,870 --> 00:08:52,930 The second challenge humankind is facing related to the fact that our energy infrastructure heavily 59 60 00:08:52,930 --> 00:08:58,940 depends on the fossil fuel like oil and coal and gas. 60 61 00:08:59,050 --> 00:09:08,050 Fossil fuels are nothing but millions and millions of years of solar energy stored in the form 61 62 00:09:08,050 --> 00:09:09,910 of chemical energy. 62 63 00:09:09,910 --> 00:09:20,500 The problem is that humans deplete literally deplete these fossil fuel faster than they are generated 63 64 00:09:20,620 --> 00:09:35,230 through the photo-process in nature so that fossil fuel are not sustainable energy source in coming century 64 65 00:09:35,600 --> 00:09:47,590 we will see that we are running out of the oil and gas if we continue our rate of consumption. 65 66 00:09:47,620 --> 00:09:56,800 Another barrier is that it's technological more challenging to get the fossil film out of reserve 66 67 00:09:57,580 --> 00:10:07,690 currently left the government and companies are willing to take higher risks like we have seen in the 67 68 00:10:07,690 --> 00:10:22,800 Gulf of Mexico spills in 2010. the third challenge is that by burning fossil fuel we produce 68 69 00:10:22,860 --> 00:10:35,460 the so-called greenhouse gas or GHG like carbon dioxide that additional carbon dioxide created by humans 69 70 00:10:35,700 --> 00:10:46,650 activities is stored in our oceans and the atmosphere most scientists saying that they increase in carbon 70 71 00:10:46,650 --> 00:10:59,560 dioxide is responsable for global warming and climate change which can have destructive consequences 71 72 00:11:01,640 --> 00:11:11,600 so humankind is looking for alternative energy resources like solar and wind.