If we mostly rely on fossil fuels, we will one day run out of energy sources. Nuclear energy is one alternative to fossil fuels. It is generated through a controlled nuclear fission reaction,where a nucleus of an atom splits into smaller parts and releases energy. The energy heats water and produces steam, which, in turn, moves the turbines. It poses safety concerns, especially after a number of nuclear power plant accidents, the most infamous and disastrous being the Chernobyl one in Ukraine, Three Mile Island one in the USA, and the Fukushima one in Japan.
After the Fukushima disaster, a number of countries started to re-evaluate their use of nuclear power, and some, such as Germany, are now working on closing down their nuclear power plants in the near future. An additional problem is the storage of spent nuclear fuel. Fuel is needed for the fission reaction to occur, and it can be reused, but eventually it has to be replaced.
Some of the byproducts of nuclear power production can be reused in other industries such as medicine or weapon production, but most of the material has to be stored as radioactive waste. Currently each country has their own storage systems for the spent fuel. They include repositories in geological structures or the ocean floor, as well as storage in spent fuel pools or casks. This poses problems and risks such as costs, leakage, running out of storage, and hostile attacks on the storage facilities.
A safer alternative that is currently being researched is to produce power from nuclear fusion, a reaction that releases energy when several nuclei collide at high speed and join into a new nucleus. This happens because when two nuclei are at a very close proximity to each other, the forces that repel the nuclei are weaker than the forces that attract them together. Similar to nuclear fission, this reaction produces radioactive waste, but this waste will cease to be radioactive after about one hundred years, compared to thousands of years with nuclear fission.
The materials needed to produce this reaction are also less costly. At the moment, fusion reactions require high amounts of energy to facilitate, but researchers are working on ways to make this reaction produce more energy than it requires and make it economical. Other alternatives include using renewable power sources, such as energy from waves, sunlight, and wind. At the moment these alternative sources are not developed enough to replace fossil fuels.
However, thanks to the subsidies provided by some governments, and also because these energy sources are much less harmful to the environment than the non-renewable ones, they are becoming more and more popular. Solar energy experiments started in , but this technology was not widely used until recently. In recent years, solar industry is developing very rapidly due to demand and subsidies from governments and international organizations.
Solar farms, which are large areas covered with solar panels, were first built in the s. Most often solar energy is collected and electricity is generated by means of photovoltaic panels. Sometimes heat engines are used in which solar energy heats water and resulting water vapour rotates the turbines, which in turn rotate generators. Wind energy has been used by humans for a long time.
The first major use was in sailing, as far as years ago. Windmills have also been in use for hundreds of years. The first wind turbines were created in the s. Tidal energy has also been used since the time of the Roman Empire, but the energy of waves and currents has only been used recently. In recent years stations that harvest wave, tidal, and current energy are being built and tested. While the idea of generating energy from marine power is not new, devices that harvest this energy on a large scale need to be further developed and tested.
This is mainly due to high costs of building such power stations, and to the lack of advancement in current technologies. Marine energy has a great potential to provide energy for large populations.
Biomass or biofuel generates energy when plant material is burned. During this process solar energy that plants generated through photosynthesis is released as heat. It is widely used in everyday life, for example to provide warmth for heating and cooking, and also as fuel for transportation.
Alcohols and oils can be made from plants, and animal fat-based biofuel is also in use. One variation of biofuel, biodiesel, is used in the automotive industry both as an additive to other diesel fuels, or by itself. The Earth stores energy in its core in the form of heat. Until recently, this energy has been accessible mostly in the areas that lie around the borders of tectonic plates, where hot springs are present.
Now, geothermal wells are created to have access to this energy more widely. This is a costly process, however. Hydroelectric energy is another alternative to fossil fuels. Hydro generated power is considered by many to be clean energy with little negative environmental impact. Indeed, with this energy source greenhouse gas emissions are not a problem as they are for fossil fuels. Hydroelectric energy is generated by water flow. It has been in use by humans for a long time. A watermill is one example of using this energy.
Currently, electricity is generated by harvesting kinetic energy of flowing water of rivers, or potential energy of water in reservoirs. This energy moves water turbines. The dams use the height difference between the reservoir from which the water flows, and the river into which the water flows. Despite the positive aspects of hydroelectric energy, numerous problems exist with its generation.
For example, displacing and damaging habitats when building dams causes considerable harm to the biodiversity. As a result of building dams plants and animals become cut off from the resources, normally available in their ecosystem.
For example, fish may not be able to go upstream to lay eggs, and may be unable to adjust to the new environment. Displacement of people due to dam construction is a humanitarian issue in some countries where construction is not regulated by the public and the government.
One of the most notorious dam projects known for human rights violations and environmental problems is the Three Gorges Dam project in China. While building this dam, over 1. This is a problem because human and industrial waste on the flooded territory polluted the water. Scientists worry that creating a reservoir of this scale threatens increased landslides this is already a problem and potential for earthquakes.
Since the Chinese government has acknowledged some of the problems with this project, including the increased frequency of earthquakes.
Energy in nutrition and exercise is usually measured in kilojoules or food calories. One food calorie is equivalent to one kilocalorie or calories in the scientific notation.
This is about 4. One food calorie is formally defined as the amount of energy needed to raise the temperature of one kilogram of water by one degree in the Kelvin scale. There are 9 food calories, or simply calories per gram in fats, 4 calories per gram in carbohydrates and proteins, and 7 calories per gram in alcohols. Some other substances also contain calories.
This energy is released during metabolism. When dieting, people often calculate calories consumed through food and drink, and expended through exercise to determine whether they eat more or less than their daily calorie needs.
The idea behind calorie counting is to eat fewer calories than the daily need, although most dietitians and doctors recommend that it is dangerous to regularly eat fewer than calories per day.
The daily needs are calculated using formulas that are based on a person with average metabolism. Nonetheless, most sources for healthy nutrition and exercise recommend tracking the daily calorie intake. Calorie density or energy density is a useful concept in nutrition. It refers to the amount of calories per gram of food. Foods low in calorie density often have a high water content. They fill the stomach and give the feeling of fullness with fewer calories than a food high in calorie density would.
For example, there are calories in grams of chocolate just a little less than half a cup , which is about the same as in grams 1. Perhaps, it is easier to imagine that one chocolate candy contains about the same amount of calories 50 as a little over a table spoon of turkey, or 6. If one compares the feeling of fullness after eating 6 cups of cucumbers and one chocolate candy, it is very likely that eating the cucumbers will make the eater feel full, while the chocolate, on the other hand, fuels a desire to eat more.
Knowing the calorie density of foods is, therefore, very useful for people who are trying to eat fewer calories. However, while it is true that most unhealthy foods are high in fat and sugar and are also high in calorie density, anyone on a path to healthy living has to consider not only the calorie content of foods but their nutritional value as well.
Nutrient density is a similar concept; it compares the amount of nutritious elements such as vitamins, dietary fiber, antioxidants, and minerals, to the amount of energy in a given food. Kelvin is 7. Enter the value of Kelvin and hit Convert to get value in Joule. Check our Kelvin to Joule converter. Need a reverse calculation from Joule to Kelvin?
You can check our Joule to Kelvin Converter. How many Joule is 1 Kelvin? How many Kilojoule is 1 Kelvin? How many Megajoule is 1 Kelvin? How many Microjoule is 1 Kelvin?
Kelvins to Joules Converter Units of measurement use the International System of Units, better known as SI units, which provide a standard for measuring the physical properties of matter. A softUsvista venture! Facebook Twitter WhatsApp.
Converting Joule to Kelvin is easy, for you only have to select the units first and the value you want to convert. If you encounter any issues to convert, this tool is the answer that gives you the exact conversion of units. You can also get the formula used in Joule to Kelvin conversion along with a table representing the entire conversion. Units Converters. Hertz Smallest. Joule Base. Gigatonne of Oil Equivalent Biggest.
Result 1 Joule is equivalent to 7. Home » Energy » Joule to Kelvin. Formula Used. Other Joule Conversions. Joules to Kelvins Conversion J stands for joules and K stands for kelvins.
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