It was a pair of Italians who first used metal combinations to make electricity. Luigi Galvani noticed that preserved frog legs in his laboratory twitched in the midst of thunder and lightning storms. Working off of this observation, he found he could induce more twitching by touching frog legs with various metals. He called this phenomena "animal electricity." Alessandro Volta dispensed with the frog legs and substituted stacks of metal plates separated by cardboard soaked in brine, producing a voltage.
Copper and Zinc. Copper and zinc produce electricity when combined with the phosporic acid found in potatoes.
Through further experimentation, Volta found copper and zinc produced the strongest, most consistent voltage of the metals available to him. He further found that different combinations of metals produced better results. Pairing zinc, lead, tin or iron with copper, silver, gold or carbon produced voltages. Using the same metal does not produce a voltage because there is no potential difference between them. These metals in combination with an electrolyte such as brine or citric acid produce electricity, but they are not rechargeable and eventually stop producing electricity as the hydrogen atoms in the electrolyte get used up.
Lead-Acid. The sealed lead-acid battery found in most automobiles today goes back to French physician Gaston Plante’s 1859 design of a cell consisting of lead electrodes and sulphuric acid. This design produces electricity only after charging, when electrons are introduced into one of the lead electrodes, turning it into the cathode and converting it to lead oxide. This creates a potential between the two electrodes, producing electricity. With their high content of lead and acid, these batteries can be harmful for the environment when not disposed of properly.
Nickel-cadmium and Nickel-Iron. Edison replaced cadmium with iron, resulting in a cheaper but less efficient battery. Wlademar of Jungner of Sweden introduced the nickel-cadmium battery in 1899. Rechargeable like the lead-acid cell, this battery did not initially enjoy commercial success because of the prohibitively high costs of materials. Thomas Edison substituted iron for cadmium in 1901, producing a cheaper but less efficient cell given to self-discharge and poor performance at low temperatures. Ni-Cad became popular with the development of an improved pole piece in 1932, resulting in a longer-lasting and more efficient battery.
Lithium-Cobalt Oxide. The lithium-ion family of batteries use a variety of metals to produce electricity. Powering cell phones and laptops, the metals producing electricity in this cell consist of a cobalt oxide cathode and a graphite anode. The widespread use of these batteries creates more chances of failure: metal fragments reach the core and cause a short circuit, resulting in rapid discharge and increased heat. This heat can damage the components of the object it powers. Therefore, phone and laptop users must be vigilant when it comes to excess device heat.
Modern Technology
There is little doubt that technology impacts the world to a startling degree. For example, business people around the globe use computers to perform work-related tasks. Some of the impacts of modern technology are positive, but others are not. Looking at a list of the advantages and disadvantages of technology is useful because it provides a means by which an individual may assess whether technology implementation is worth potential risks.
Efficiency and Productivity. An increase in technology generally means that tasks are completed faster and more efficiently. This translates to increased productivity. From the business standpoint, this is definitely an advantage, since increased productivity means better sales, services or manufacturing.
Job Loss. When an organization uses technology properly, the technology typically cuts the number of hours that need to be worked. This increases profit for the organization because it doesn’t need to pay workers to remain on the job site. However, if the technology cuts the number of hours drastically enough, some individuals may lose their jobs entirely because the technology essentially completes the tasks that the employee originally did. Factories are the best example of this - as more and more robots complete assembly line tasks in an automated way, there’s less of a need for physical workers. According to Small Business Bible, jobs are created by technology too, such as information technology specialist positions.
Finances. It is debatable whether or not technology is financially a disadvantage or advantage. On one hand, technology is cost effective, according to Small Business Bible - technology may boost revenue and profit through increased efficiency, productivity and limited man hours. However, a business may lose this revenue and profit simply because they have to support and update all of the technology they use. For example, a business may reduce the number of office employee hours with a handful of software programs, but it then may have to pay a technology consultant fees for installing and answering questions about how to use the programs.
Precision. Technology means that people can perform tasks with an incredibly high degree of accuracy. For example, in medicine, machines can measure the exact amount of oxygen a person is taking in or make an incision to within millimeters.
Health. Technology may cause numerous health problems. For example, according to Practice, Medical News Today, PR Log and Poynton, scientists, researchers and doctors such as Darius Lakdawalla, Tomas Philipson, Amy Drescher and Charles Poynton are concerned about the links between technology, obesity/heart problems, eye strain, deafness and muscle issues. Waste from technology such as the used fuel and emissions from factory machines may pollute the environment, disturbing ecosystems and making people sick.
Nuclear Energy
Nuclear power is a controversial source of energy, having both unique advantages and disadvantages. Energy is created through nuclear fission using uranium-235 or plutonium-239 isotopes. Large amounts of kinetic energy are produced during this process and converted into electricity. The Nuclear Regulatory Commission oversees the nuclear power industry in the United States.
Environmental Impact.
Nuclear power has a different type of environmental impact than other energy sources. Abnormal events at nuclear power plants, such as a release of radioactive material following a damaging earthquake, can have severe consequences for the environment. Extensive backup systems and modern technology can reduce the chance of these events happening. The waste produced is discharged, high-level radioactive spent fuel and low- to intermediate-level radioactive waste. A modern nuclear plant produces about 1,050 cubic feet of compacted waste a year; compare this to a 1000-megawatt coal plant sending about 24,250 tons of nitrous oxides and 48,500 tons of sulphur oxides into the atmosphere each year.
Security Issues
Nuclear power plants must be thoroughly protected from terrorist attacks. Stolen fuel rods can potentially be used to make a "dirty bomb." An aircraft attack on a plant could release radioactive material. Use of nuclear power, however, can help a country reduce its dependence on external fuel sources and avoid national security threats and economic issues if those fuel sources become unavailable.
Costs
Nuclear power plants have high startup costs. Plants must invest heavily in containment systems and emergency plans. Extensive backup systems must be built and contingency plans must be developed to handle the rare threat of core meltdown. The cost of a nuclear plant’s future decommissioning must be considered and funded, as well. Despite these costs, the uranium used for nuclear power plants is a heavily concentrated source of energy that transports easily.
Waste Storage
Radioactive waste must be placed in long-term storage systems. Spent fuel rods emit dangerous radioactivity that slowly decreases with time through radioactive decay. The United States has no permanent facility for high-level nuclear waste, so spent fuel is commonly stored in sites near nuclear power plants.
Plastics
Plastics have many advantages over other materials. Aside from the many shapes and types of plastic bottles, plastics can be recyclable. Plastic bottles are widely used and can be found in supermarkets, vending machines, as a disposable bottle, or a reusable water bottle. Plastics are also cheap and reliable. Plastics have even moved into new markets, like the wine and beer industries. This is because plastics have some advantages over glass.
Plastic Properties
Plastic is synthetic, therefore it can have many properties. Plastic can be hard, strong, durable, soft, flexible, heat resistant, shatterproof and corrosion resistant. This means the container will not break like glass if dropped, and can sit on a shelf for a long time. Plastic bottles are also lightweight, and transparent, so you can see the contents.
Recycling
Plastic is a recyclable material, which benefits the economy and the environment. Industries have also started using less plastic per bottle, which when combined with recycling, can save resources and finances. From the environmental point of view, less resources means overall less pollution. The recycling of plastic is also a widely accepted practice, which means recycling bins are never far from trash cans.
Skepticism
Some skeptics believe that plastics are dangerous and can contaminate water or food because of their inherent chemical properties. Plastics can be poisonous. There are many forms of plastics with different chemical polymers. On the other hand, plastic bottles are safe to drink out of because the type of plastic used and its process is made for the purpose of holding safe drinking water. As long as plastics are used as intended, meaning using microwave safe bowls in a microwave, consumers have little to be concerned about.
Pneumatic Equipment
Pneumatic equipment operates under the power of compressed air. Most pneumatic equipment requires several supplemental components to operate properly. Most electrically-powered tools including jackhammers, nail guns, sanders, staple guns and buffers are available in pneumatic models. In almost every case, the pneumatic tool outperforms the electric tool. Despite the numerous benefits with pneumatic equipment, this type of equipment is not without limitations.
Air Compressor
All pneumatic equipment operates under air compressors. The air compressor basically compresses a given amount air to a specific pressure. Consumers can use this pressurized air to power certain equipment like pneumatic buffers, jackhammers, sanders and nail guns. There are advantages and disadvantages in requiring air compressors to operate. The obvious disadvantage with air compressors is that they can be quite heavy and bulky. An advantage is that they make pneumatic tools portable since a compressed air tank can be taken almost anywhere.
Maintenance
Pneumatic equipment requires regular maintenance. Sources at American Pneumatic Tools recommend that pneumatic equipment owners regularly inspect and maintain their pneumatic equipment to maintain a safe work environment while the equipment is in use. Monster Guide claims that operating pneumatic equipment can be messy because a lot of lubrication and oil are needed to keep them operating smoothly. Oil levels should always be kept at manufacturer-recommended levels.
Safety Measures
Pneumatic tool operators should employ hearing protection while operating most types of pneumatic tools to avoid injuries to the ears, according to The Tool Hut. Safety glasses should be worn to avoid damage to the eye, according to Ask the Builder. When operating pneumatic equipment produces excessive dust, it is recommended that the operator employ a dust mask or respirator. Pneumatic staple gun operators may choose to wear steel-toe boots to prevent injury to the feet and toes.
Warnings
The oil and lubricant used in pneumatic equipment can spit out around the operator’s workspace, which can make for an unsafe environment. Shards of material may fly off a workpiece while it is being operated under pneumatic equipment. In cases where pneumatic equipment is going to be operated near bystanders, protective shields can be put in place to protect the bystanders. Signs should be posted to inform the public that they are near active pneumatic equipment.
Solar Energy
Fuels commonly used as energy sources (e.g., petroleum) are problematic in that they are limited resources and produce harmful emissions related to global warming. As a result, alternative sources of energy have been sought out. One such source under investigation and development is solar energy.
Cost
A disadvantage of using solar energy is that the equipment necessary to harness it is expensive. On a more basic level, it is the technology within the equipment that comes with a high price. For instance, second-generation solar cells apply a thin film of a material such as silicon over the main material of the cell (e.g., glass). Such cells work by using the photovoltaic effect to convert light into electricity directly. Second-generation cells currently allow less material to be used than with first-generation solar cells and therefore reduce costs, but the process of producing the cells still does not exceed other fuel forms in terms of cost efficiency. Technology is continually improving (third-generation cells already are being devised and tested), thus the cost of solar energy equipment probably will go down over time, but the current standard is still lacking in terms of cost effectiveness.
Light
An obvious problem with solar energy is that it only works when there is sunlight available. This means that solar energy plants cannot harness solar energy at night. It is also difficult to harness the energy in areas nearer to the earth’s poles---i.e., areas that do not receive as many hours of sunlight per day. An alternate fuel source still would be needed for energy production during nighttime hours.
Space
The equipment needed for solar energy takes up large amounts of space---technology is not yet advanced enough (although it is becoming so) to provide optimum efficiency levels with small solar panels. Additionally, even when the panels are efficient given the technology available, the location of the panels doesn’t always provide good performance, such as if the panels are blocked by other buildings.
Supply and Demand
Solar energy is not prone to the politics of supply and demand pricing due to the fact that no fuel is needed to harness the energy. This means that costs can be kept stable regardless of the state of the economy.
Eco-friendliness
Unlike some energy sources such as petroleum, solar energy is completely eco-friendly. It does not produce any emissions that can lead to global warming and does not deplete resources available on the earth.
Renewability
Sources of energy that have been used in the past (e.g., petroleum) will not last for much longer, and although they are renewable, it takes a long time to produce more. In contrast, there is enough energy left in the sun to last billions of years, thus solar energy can be considered more renewable than the alternatives.
Sources of Power
Power provides the energy to drive man’s activities. Power-generating companies derive power from naturally occurring sources of energy and fuels, the most common of which is oil. You may classify all the available power sources as either renewable or nonrenewable sources of energy.
Solar Energy
For centuries, people have harnessed the sun’s energy in form of light and heat using technology that continues to evolve. The sun is a renewable source of energy because it does not diminish regardless of how much it is exploited. Photovoltaic systems harness solar energy and convert it to electricity to run industries, entire office buildings and schools; solar energy can even pump water in isolated areas.
Power from Wind and Water
People are able to generate power from wind and water as well. These two are also renewable sources of energy that produce power by driving electricity-generating turbines. A variety of wind turbines ranging in size can produce considerable quantities of power, as much as several megawatts. Water, on the other hand, including steam, can drive turbines as well to generate power. Running water and wave energy are used to produce electricity in hydroelectric plants, while steam is used in thermoelectric power plants.
Fossil Fuels
Fossils fuels were formed through natural processes of decomposition of plants and animals buried under the earth’s crust over a long period. They include coal and petroleum products such as oil, paraffin and natural gas. Fossil fuels are nonrenewable in the sense that they take a very long time to replenish; we burn fossil fuels for energy at a much faster rate than natural processes can restore them.
Nuclear Energy
Nuclear energy is another arguably nonrenewable source of energy; it is sourced from chemical processes such as nuclear fission. Nuclear fission is the splitting of radioactive atoms such as uranium. This reaction produces heat that turns water into steam for driving electricity-generating turbines.
Thermal Power
Thermal power has been used as a natural form of energy for thousands of years in cooking and heating. Hot springs are just one example of this naturally-occurring thermal energy. With today’s rising power demands, geothermal power plants are attractive options for their cheap, environmentally-friendly energy production. However like all power sources, thermal isn’t perfect, and disadvantages temper the strengths.
Financial Costs
One of the primary advantages of thermal power is that the generation costs are extremely low. No fuel is needed to generate the power, and the minimal energy needed to pump water to the Earth’s surface can be taken from the total energy yield. Even considering transport, geothermal energy is estimated to save 80 percent of the costs associated with fossil fuels, such as oil and natural gas. The principal financial disadvantage of a geothermal system is its high initial installation costs. The longer a plant is operational, the more it pays for itself in the long run.
Environmental Impact
Thermal power is revered by environmental activists because it is completely renewable, does not use fuel to produce power and has virtually no emissions. It also helps reduce global warming and pollution and requires far less land than a coal mine or oil field. The only environmental disadvantage is the occasional release of harmful gases. Since thermal power operates by drilling into the Earth’s mantle, some poisonous gases can escape. These gases can be a danger to plant workers, who must wear protective equipment, but have little impact once dispersed into the atmosphere.
Job Creation and Hazards
Thermal power facilities create a number of jobs for local communities. Researchers, scientists and drilling workers are among the specialists needed for safe and effective operations. Disadvantages in this area involve limited workplace hazards, such as crystalline silica dust and exposure to extremely hot steam and water mains. Fortunately, these dangers are minimal, especially compared to other energy industries, like fossil fuels.
Location
A main disadvantage of thermal power plants is that they can only be constructed in areas where temperatures below the Earth’s surface allow for the production of steam over a long period of time. The type of rock in the region must also be easy to drill through. Extensive research is needed to find these key areas; and because of their rarity, plants are sometimes forced to operate in relatively remote regions. Both of these factors contribute to the high initial cost of starting up a geothermal facility.
