Hélium-3 lunaire : la fusion nucléaire et le futur de l'humanité dans le système solaire

L 'hélium-3 (He-3) Il est l'isotope dell 'hélium. Il se compose de deux protons et un neutron. Il est rare sur terre et il est principalement utilisé dans la recherche sur la fusion nucléaire.

On croit que l'hélium-3 est plus répandue sur la Lune (Dans la couche supérieure de la roche régolite où il a été inclus par le vent solaire sur des milliards d'années) et géants de gaz la système solaire (Les restes de nébuleuse solaire).

L'hélium-3 est présent dans les roches lunaires en une quantité de 0,01 parties par million. La masse de l'hélium isotopique est égal à 3 3.0160293 u.

Du point de vue scientifique, cet isotope est important, car on croit qu'il peut être utilisé comme source d'énergie pour les centrales électriques fusion deuxième génération.

Selon les données enregistrées en 2009 par la sonde orbitale chinoise Chang'e 1, les réserves en hélium 3 de la Lune s’élèveraient à 100 000 t. Il est incorporé au régolite ou enfoui en faible profondeur de la surface. Lorsqu'on sait que 200 tonnes permettraient de satisfaire les besoins énergétiques des États-Unis et de l'Union-Européenne pendant une année, que cette énergie permettrait aux Terriens de combler leurs besoins en énergie pour des siècles, cela incite les enthousiastes à y voir un moteur puissant à son exploitation. En effet, le coût d'exploitation d'une tonne d’hélium 3 serait de l'ordre de 1,5 milliard de dollars (2005), alors que la même quantité d'énergie coûte 10 milliards de dollars en équivalent pétrole faisant de cette ressource un sujet d'intérêt commercial à une reconquête de notre satellite dans un avenir proche…

*Remarquez que l'hélium-3 ne pollue pas lors de la fusion de deuxième génération à comparer au tritium : en émettant un proton plutôt qu'un neutron.

Le tritium est un élément clef de la fusion nucléaire, par la grande section efficace et l'énergie dégagée par sa réaction avec le deutérium.

Toutes les centrales produisent du tritium qui est un résidu de l'exploitation des réacteurs. En France, « il est stocké sur site, dans des réservoirs prévus à cet effet, avant d'être rejeté conformément aux autorisations de rejets, après avoir été contrôlé ». Des limites de rejets sont imposées pour chaque installation, par arrêté (ex : 80 Bq/L à ne pas dépasser pour les rejets de la centrale nucléaire de Chooz B en 2005).

Controversy over alternative energy

Biomass power renewable energy

Biomass in ecology

  The definition of biomass in ecology is the mass of living organisms in a given area or ecosystem at a given time. Biomass can refer to one or more species biomass which is the weight of one species in the community or to the community biomass which is the mass of all the species in the community. Biomass can include plants (phytomass) and biomass (zoomass), and in our present case, it's the weight mass of organically bound carbon number in tonne present who will be considered for its energy potential.

It is estimated that:

• the total live biomass on Earth apart from bacteria is about 560 billion tons of carbon 
•  The world bacterial biomass was calculated to be 350-550 billion of tons of carbon, equal to 60%-100% of carbon in plants.
• 95% of the biomass is in the continents
• only 5-10 billion of tons of carbon are found in the oceans
• on land, there's 1000 times more plant biomass than animal biomass 
• 18% of all this plant biomass is eaten by animals on land
• in the ocean, there's 30 times more animal biomass than plant biomass
• most plant biomass on the ocean is eaten by animal's biomass 
• the Earth's total annual production of the biomass it is estimated to be 100 billion tons of carbon a year. 

 Biomass(energy)

  Biomass power is the energy derived from vegetable or animal matter which can be harnessed to produce electricity. In the field of bio-energy, biomass is the part of it still usable as a source of energy; either directly by combustion or indirectly after methanation (biogas, or its uncluttered version bio-methane).     
  Wood is still the largest biomass energy source today. Natural wood logs are used on a large scale, this includes also branches, forest residues, dead trees, municipal wastes, etc... The largest source of energy from wood is pulping liquor or "black liquor" a waste product from processes of pulp, paper, and paperboard industry. It's used in the pulp mill's industry. They use recovery boilers to burn the black liquor to create and produce steam. Wood is considered an alternative energy source because it pollutes less than fossil fuel, and it is being considered a renewable energy source because plants crop can be replaced with new growth.
  Pellet fuels are made from organic compressed matter or biomass. Pellets are made from one of any five general categories of biomass: industrial waste and co-products, food wastes, agricultural residues, energy crops, and virgin lumber. Wood pellets are the most common fuel pellets, and they're made from compacted sawdust and related industrial wastes.

  Many crops are of interest for their ability to provide high yields of biomass, like sugarcane. Bagasse, its residue is produced in great quantities. The production of bagasse is evaluated at 250 million tons a year, it can serve to feed animals. It has a poor nutritive value and can be fermented by white-rot fungi to produce enriched animal feed. Bagasse and other sources such as cornstarch who are rich in sugar can be fermented to produce first-generation biofuels. Bio-ethanol is an alcohol that can serve directly in a fuel cell to produce electricity or as an additive to gasoline. But utilizing food-based resources for fuel production can only aggravate the food shortage problem. Second-generation biofuels, on the other hand, utilize non-food biomass products such as municipal and agriculture wastes. Despite being the favored alternative of production of bio-fuel, second-generation biofuels isn't achieved yet due to technological issues. Energy derived from biomass is projected to be the largest non-hydroelectric renewable source of electricity in the U.S. between 2000 and 2020.

  Some biomass products like ethanol and wood have a poor calorific value, compared to the energy released by burning 1 tonne of oil equivalent 0,3215 (toe).
The tonne of oil equivalent (toe) is a unit of energy, it's approximately 42 gigajoules or 11 600 kWh. And a tonne of crude oil is approximately 7,3 barrels. 
   

The calorific value in comparison with crude oil: 

• 2,2 tonnes of wood = 1 toe 
• 1,5 tonnes of high-quality coal = 1 toe
• 1 ton of uranium (in light water reactor) = 10000-16000 toe
• 1100 m³ of natural gas = 1 toe 
• 1 tonne of diesel = 1,01 toe
• 1 tonne of bio-ethanol = 0,64 toe

  Electricity production comparison value:

• geothermal electricity :              1MWh = 0,860 toe
• nuclear electricity :                    1MWh = 0,261 toe
• fossil or renewable electricity :    1MWh = 0,086 toe
• Natural gas electricity :              1MWh = 0,077 toe

Solar power technologies pros and cons

Controversy over alternative energy  

The costs of solar energy(part 4)

  Photo-voltaic solar panels system on your households who produce electricity are photo-voltaic cells, connected together to a solar module, who transform solar radiation into electricity. Generally, several modules are grouped together to form an installation. They are usually installed on the roof so that the slope is sufficient for the snow to slide on the walls of glass and to better capture the brightness of the Sun.

   DC power generated from solar radiation is used to power a device or recharge a battery. The power must first go through an inverter before being converted to 110V and routed to the house. Generally, people are connected to the electricity grid and work with a battery, because they can get supplies from the electricity company if their needs are not met by solar energy. Off-network users use batteries that provide power, regardless of brightness and variations in demand. In eastern Northern-America, these batteries provide a stable diet during the shorter days of autumn and early winter.

   All that consumes electricity can be powered by photo-voltaic panels, namely lighting, appliances, computers, small electrical appliances. However, for anything that generates heat, such as heating the house and water, it is better to use another technology: solar thermal energy. Indeed, it is more efficient and less expensive to generate heat with this technology.

   By cons, the costs are very important if you have the idea of converting your single family house into solar energy. But the investment can be worth the cost, even in Quebec. In Quebec, it is estimated that electricity produced with photo- voltaic panels cost six times more than the price of residential electricity. A kWh produced with solar photo voltaic energy costs about $0.42 compared to the $0.07 per kWh requested by Hydro-Quebec.

   Even if Hydro-Quebec does not go to the residence or if the cost of connection to the network exceeds $15,000 to $20,000, it is advantageous to install solar panels. It all depends also on where you live, how much you pay for your electricity in kWh in your state or province. How much you spend on electricity each month and how much you think you'll be saving with your solar panels system each year...

   For example, the average annual electricity use for Canadian and U.S. households is 11,000-kilowatt hours (kWh). Multiply that by the national average electricity rate as of September 2016 ($0.1287 per kWh) and you'll find that the typical American family is spending over $1,400 a year on electricity alone.

   Then, you'll have to consider also the volatile nature of electricity prices, determine what utility rates will be in years to come. When you compare the cost of utility electricity with solar home, you should keep in mind that you can expect electricity rates to increase annually. Over the past decade, national electricity costs increased by 2.2% per year.

Average solar panels installation:

• System size: 5 kilowatts (the national average)
• Electricity demand: 11,000kilowatts-hour per year (national average)
• Utility rate inflation: 2,2%
• Percent needs meeting by solar panels: 84%
• Electricity rate
• Ownership of the solar panels is assumed

The annual solar energy production of solar systems:

• 3kW                    4,260 kWh
• 4kW                    5,680 kWh
• 5kW                    7,100 kWh
• 7kW                    9,949 kWh
• 8kW                   11,360 kWh
• 10kW                 14,200 kWh
• 12kW                 17,040 kWh
• 15kW                 21,300 kWh

Cost of electricity in kilowatt per hour:

• Quebec:           7 cents kWh
• Toronto:         14 cents kWh
• Moncton:        12 cents kWh
• Chicago:         17 cents kWh
• New-York:      29 cents kWh
• Boston:           30 cents kWh

So, if you live in a place like the province of Quebec, it'll take you as 4 times longer to get your return of investment on your solar panels system compare with how much you pay for your electricity bills in Boston, Massachusetts or in New-York.

Examples of costs for equipment (installation included)

Prices are approximate

Example 1

Medium sized family households

Not connected to the utility grid's

24 panels = 2,880 watts / $15,000

12 batteries / $6,000

Other equipment / $7,000

Total: $28,000

Example 2

Chalet, weekend use

Not connected to the utility grid's

8 panels = 960 watts / $5,000

6 batteries / $3,000

Other equipment / $4,000

Total: $12,000

Example 3

Small hunting & fishing hut, RV

Not connected to the utility grid's

2 panels = 240 watts / $1,250

2 batteries of 12 volts / $400

Other equipment / $550

Total: $2,200

Solar power technologies pros and cons

Need to structure solar energy technologies. (Photo credit: Wikipedia)

Solar power technologies pros and cons

Controversy over alternative energy  (part 3)

Solar and renewable energy, Chinese business

  The Sun is at the origin of most of all the energy sources on Earth except for nuclear energy and deep geothermal energy. Solar energy comes from nuclear fusion at the centre of the Sun, the energy spreads in the Solar system and the Universe in the form of an electromagnetic radiation, photons, and infrared radiation. A fraction of the electromagnetic energy from the Sun is coming true the atmosphere, which absorb a part of it and reach the surface of the Earth.

  The conversion of light in electricity called photo-voltaic effect was discovered by the French physicist Edmond Becquerel in 1839, but we'll have to wait a hundred years before scientists deepen and exploit this phenomenon of physics. It's the space exploration and NASA that will really make solar energy progress. The space industry will invest a lot of funds in the development of solar panels. Solar panels are the only non-nuclear way of powering satellites with energy, moreover, solar energy is a constant source of energy in orbit. 

  While President Trump promises to put American coal miners back to work, China is moving the opposite direction. China's betting big on renewable energy. It commits in January to invest $367 billion in renewable power generation: solar, wind, hydro and nuclear by 2020. The investment will create 10 million jobs in the sector. Beijing is investing hundreds of billions of dollars and creating millions of jobs in clean power. China currently boasts 3,5 million jobs in clean energy, by far the most in the world, according to the International Renewable Energy Agency. 

  China has built vast solar and wind farms, helping fuel the growth of major industries that sell their products around the world. It's 2,5 million people working in the solar power sector alone in China, compared with 260,000 people in the U.S. China produce 63% of the world production of solar photostatic (PV) and it has emerged as the world's largest manufacturer of 2015. Solar power in the People's Republic of China is one of the biggest industries in China. Chinese solar panels production reportedly quadrupled between 2009 and 2011 to surpass the entire global demand. The flood of Chinese panels was one of the reasons why world prize crashed by 80% between 2008 and 2013. As a result, The United States and EU accused China of dumping its solar panels in Europe at below the cost-prizes. 

  The country has become a major manufacturer and exporter of renewable energy technology, supplying two-thirds of the world's solar panels. China has also a strong grip on wind power. It produces nearly half of the world's wind turbines at a rate of about two every hour.

  

There are two large families of short-cycle solar energy to distinguish:

• thermal solar energy, the use of radiation heat of the Sun and also CSP concentrating solar power system by using mirrors or lenses of a large area into small a small one

• PV photo-voltaic energy, the use of radiation itself to produce electricity

 Solar energy received at a point of the globe depends on:

• solar energy sent by the Sun and arriving in the immediate vicinity of the Earth (decadal, seasonal, and punctual fluctuations of the Sun)
• cloudiness (clouds, fog, etc.) which varies enormously from one place to another
• latitude, season, and time, which affect the height of the Sun and therefore on the energy received per unit area, as well as on cloudiness as a function of the local climate

 As a renewable energy source, the part of the world finale consumption's production of electricity of photo-voltaic solar panels was estimated to be 1,2% in 2015. Solar energy from solar panels has multiples advantages: it's a renewable and inexhaustible energy source because it's coming from the rays of the Sun. It's a clean energy source because its respects nature and the environment. It's reliable, installation is easy to use, the cost of operation is low and maintenance is reduced.

  

  

Solar energy advantages and disadvantages

Solar power technologies pros and cons

Controversy over alternative energy  (part 2)

Voltaic cells production 

   From an electric point of view, a photo-voltaic cell is the equivalent of a power generator to which a diode has been added. In a photo-voltaic cell, a semiconductor is exposed to the light, a photon with a sufficient energy pulls off an electron from the matrix of the semiconductor, creating a hole. The principle of the voltaic cell is to force the electrons and the holes to go toward the opposite side of the material and created a difference of potential, a voltage in between the two faces like in a battery.

   A semiconductor is generally made of silicon because of its properties, cheap price and its abundance in nature. In the semiconductor's production, the introduction of small impurities into the intrinsic semiconductor is made for the purpose of modulating its electrical properties. The dope material is referred to as extrinsic semiconductor.
  In the superior layer of a semiconductor doped N voltaic cell exists a larger quantity of free electrons compared to the intrinsic material (non-doped), hence the name superconductor doping N, for electron negative. The doping N production consisted of increasing the density of electrons in the semiconductor. The atoms or the elements needed generally have 5 valence electrons to participate in the chemical bond, and they are usually in the IV column of the periodic table chart: P, As, Sb, are commonly used in the production… Those atoms embedded in the crystal lattice will present 4 covalent bonds and a free electron. This electron who's weakly bound to the atom can easily be excited toward the conductive band. When the doping N is sufficient, the number of electrons surpass by far the number of holes, and they become majority carriers. 

   The doped P semiconductors production consists of creating a deficit of electrons and to increase the density of holes in the matrix. And then the semiconductor will be considered positively charged, hence its name superconductor doped P for positive charge. To do this, we include a certain number of atoms low in electrons in the semiconductor. For silicon semiconductors, trivalent atoms will be embedded in the intrinsic (pure) matrix and it is boron atoms that are used most often in the fabrication of the P semiconductors. This atom: boron with his 3 valence electrons can only produce 3 covalent bonds with his 4 neighbours, creating holes in the structure. Holes who will be filled with electrons from silicon neighbours; thus displacing the holes. When the doping P is sufficient, holes surpass by far the number of electrons, and holes become majority carriers.

Hydroelectricity pros and cons

Hydroelectricity pros and cons

Controversy over alternative energy  (part 1)

   

  Hydroelectricity is a good alternative energy source to fossil fuel (wood, coal, natural gas, and oil) for the environment. Hydro-power produces a 100 times fewer greenhouse gases than coal-fired power plants. It's called hydroelectricity and it's the most popular clean energy source in the world and it counts for 16% of the world's production, but well behind fuel fossil energy production. It's an affordable energy source and it's easy to stock electricity, compared to solar panels or wind power turbines. Those technologies need batteries to stock electricity, hydroelectricity not, it's a water reservoir and you just open the van when you need to have electricity. It's a renewable energy source as long as you have the water supply. 

     Hydroelectricity and evaporation water supply

  One of the major problems of hydroelectric water retaining dams in hot countries like Egypt and Namibia in Africa is the stagnation of water and its evaporation. In Egypt 10 cubic kilometers of water is lost to evaporation each year: that's 12% to 18% of the Nil water. The champion in Africa is in Namibia whose one of its dams dispense 14 millions cubic kilometers of water and loose 45 millions cubic of water each year due to evaporation, no question it's for sure more than its production of electricity. 

  

  Hydro-power Greenhouse gases debate Some say hydro-power doesn't emit carbon dioxide or just a few. At Hydro-Quebec their numbers say that it's a clean energy source and it produces the same quantity of green-gases in kWh than wind power turbines and 4 times less than solar panels technology at their fabrication. In fact in 2009 in Quebec, thanks to hydro-power, the electricity sector accounts for only 0,6% of GHG emissions. The transportation sector accounts for the most with 44%.  

   But others say the opposite, hydro-power plants are emitting GHG indirectly. Their point is that when they have built the hydro dams they usually completely flood large areas of lands, full of trees, biomass and other variety of organic stuff. After the flood, the soil organic vegetation and sediments start to decompose, rut and emit methane. This decomposition produces methane which is at least 34 times more potent as other greenhouse gases. Some experts say that hydroelectricity contributes to 4% of greenhouse gases pollution emitted every year in the world. It's also said that hydroelectricity pollutes more than the aviation industry on this planet.

  

Hydroelectricity and the environmental impact

Hydroelectricity is also linked to disrupting aquatic ecosystems. It interferes with aquatic life and results in huge scale devastation. With that, also it leads to water stagnation. Stagnant water is when water stops to flow and it can be a major environmental hazard, a breeding ground for mosquitoes and parasites, an incubator for many kinds of bacteria and diseases and illnesses like malaria and dengue fever in hot countries where the temperature is ideal for it. Hydro-power plant dams are usually built across rivers to stock large bodies of water in a basin. The water loses is good proprieties, lose oxygen, sediments start to build, water stagnated and that's very bad for the ecosystems and the environment. It had been found that a lot of individuals, fishes, and others aquatic animals will perish in there by the lack of oxygen and impossibility to reproduce in their native habitats. There is a huge probability also that the fish and other aquatic creatures will find a way into the penstock pipes then to the turbines and get exterminated.

Renewable energy debate

Hydroelectricity may not be the perfect alternative energy source and the answer to all of our environmental problems. If greenhouse gases are our big concern and the control of global warming our first priority today, hydroelectricity is maybe not the final solution for to save the environment and the planet.