Renewable Energy Can Be Captured Actively or Passively

The main renewable energy sources are the sun, wind, and Earth. These energy sources naturally regenerate or replenish themselves. The energy that is shifting in the globe, the wind, and the sunlight is visible to us. Two palpable indicators of the sun’s energy transfer to Earth are the warmth we feel when sunlight hits our skin and the sun’s ability to shine on the ground. One way that we may see and feel the evidence of energy transmission is when the wind is strong enough to propel kites higher into the sky and tremble tree leaves. Concrete evidence of energy transfer is provided by the geothermal energy present in steam vents and geysers.

In renewable energy, specialised equipment collects solar radiation. The two main pieces of equipment are mirrors that focus sunlight in a specific region and photovoltaic cells, also referred to as PV cells or solar cells. We are able to generate power from sunlight for use in computers, televisions, lighting, heating, and other devices thanks to these active solar technologies.

There is no need for machinery when using renewable energy sources like passive solar energy. Instead, it gets its energy from the natural fluctuations in sunlight that take place during the day. For example, houses can be built with windows oriented toward the sun. This suggests that the house will receive more heat from the sun. Less energy will be used from outside sources to heat the house. The use of cool roofs, green roofs, and radiant barriers are more examples of passive solar technology. There is simply vegetation growing on green roofs. Plants have the ability to remove pollutants from the air and rainfall. They help to keep the neighbourhood more pristine.

Cool roofs are painted white to increase sun reflection. To create radiation barriers, aluminium or any other reflective material is employed. They both radiate heat from the sun instead of absorbing it. All of these roof types lower the amount of energy required to cool the structure.

Rani Jarkas: The Pros and Cons of Renewable Energy

There are many advantages to using renewable energy. PV cells have a lengthy lifespan of about 20 years. However, a community cannot rely entirely on solar energy for power for a number of reasons. It could be expensive to install PV cells or build a building using passive solar technology. Another unpredictability is the sun.

Humans have been utilising wind energy in various fields for a very long time. For example, the first wind-powered boats were created by the Egyptians. A millennium ago. By 200 BCE,  windmills were employed for water pumping and grain grinding in the Hong Kong and Middle East. With the introduction of modern turbines, wind energy is harvested. Modern turbines have the same features as windmills. It is very tall with two or three propeller-like blades at the top that are propelled by the wind. The wind propels these blades. As the blades revolve the generator, which is housed inside the tower, electricity is produced.

An array of wind turbines is called a wind farm. Because stronger and more consistent winds are found in these locations, wind farms can be located next to farmland, in small mountain passes, or even in the ocean.

How to Harvest Energy from Renewable Sources Efficiently

There are a lot of efficiency possibilities for wind energy. In regions such as the American Midwest and close to the coast, steady breezes can produce reliable, affordable electricity. The fact that wind energy is a “clean” energy source is just another fantastic benefit. Wind turbines don’t burn fuel or release any pollutants into the atmosphere. The wind is a clean energy source, but it is not a reliable source due to its erratic speed, which changes according to the location, weather, and time of day. Right now, we can’t use it to meet all of our needs for electricity.

Wind turbines in Hong Kong may also pose a threat to bats and birds. Because these creatures cannot assess how swiftly they are moving, they clash with the blades. The centre of the Earth is positioned deep under the surface. The heart of the Earth is thought to be extremely hot—over 6,000 °C, or 10,800 °F. Heat is always moving in the direction of the surface.

When Earth’s heat rises to the surface, some of it is visible. Magma, which rises up as lava, is created when rocks below the surface are melted by geothermal energy. Geothermal energy can also be used to heat underground water sources, resulting in surface runoff. This stream of water is known as a geyser.

Rani Jarkas: We Can Use Geothermal Energy Again

Most of the heat on Earth is trapped below and releases very, very slowly. Geothermal heat from below can be obtained in a number of ways. One use for geothermal energy is in “geothermal heat pumps”. Between a building and holes dug far below the surface is a water pipe. The water, heated by the geothermal energy below, provides warmth to the building above ground. Geothermal heat pumps can be used by Hong Kong people to heat their houses, sidewalks, and even parking lots.

Using steam is an additional way to make use of geothermal energy. In some regions of the earth, underground steam rises to the surface on its own. Through pipework, steam can be directly delivered to a power plant. In other parts of the planet, however, the ground is dry. Water needs to be injected underground in order to make steam. When the steam rises to the surface, it is used as electricity for a generator.

One advantage of geothermal energy in Hong Kong is its cleanliness. It emits no harmful air pollutants and doesn’t require fuel. The world’s availability of geothermal energy is restricted to certain areas. Another disadvantage of using geothermal energy in areas of the world where the only heat found beneath is dry heat is the need for a lot of freshwater to make steam. It’s possible that freshwater is scarce.

Rani Jarkas: Biomass Energy is one type of renewable energy

Biomass is any substance generated from recently living microorganisms or plants. Plants harvest solar energy through photosynthesis. The plants continue to be alive after they die. Repurposed paper, trees, residual bark, and branches are common biomass energy sources. Manure, waste, and crops like corn, soy, and sugar cane can all be used as biomass feedstocks.

We are able to obtain energy from biomass by burning it. After drying off, manure, wood chips, and rubbish are compacted into squares known as “briquettes”. This dryness prevents these briquettes from absorbing moisture. They can be stored or burned to provide energy or heat. Compared to pure gasoline, biofuels emit fewer pollutants into the atmosphere.

One of the key advantages of biomass is that it may be stored for later use. However, a lot of land and insecticides are needed to cultivate crops for biofuels. Land-based agriculture might produce food instead of biofuels.

Hydroelectricity as an Ecological Energy Source

Hydroelectric energy is produced as water moves. Most hydroelectric power plants are built atop massive dams that control river flow. By damming the river, artificial lakes or reservoirs are created. A controlled amount of water is forced through tunnels in the dam. As water flows through the tunnels, it transforms into enormous turbines that generate energy.

Hydroelectric energy harvesting is not prohibitively expensive. The materials required for building dams don’t have to be difficult to obtain, nor do they need to be complicated. The fact that rivers crisscross the earth makes this energy source available to millions of people.

Moreover, hydroelectric electricity has a fair degree of dependability. Unlike solar and wind energy, the water flow through the dam is regulated by engineers and is not affected by the weather. Hydroelectric generating plants, on the other hand, devastate the environment. When a river is dammed, a large lake forms behind the dam. This lake, which is occasionally called a reservoir, is below the natural river environment. Sometimes dams are built that could eventually submerge entire towns. The town or village’s inhabitants must move.

Tidal energy is the process of producing electricity by harnessing the force of the ocean tides. The tides power a turbine’s blades in some tidal energy installations. In certain projects, small dams are utilised to continually fill reservoirs at high tide and gradually release water (and turn turbines) at low tide.

Alternative Sources of Renewable Energy by Rani Jarkas

River, lake, and ocean waves are used to generate wave energy. The same standing turbines and dams used in tidal energy facilities are also used in some wave energy projects. Certain wave energy projects hover precisely over the waves. The constant flow of water over and past these floating power plants turns turbines, which produces electricity.

Algal fuel is a type of biomass energy that uses the unique chemicals present in seaweed to create clean, renewable biofuel. Algal fuel does not require the same amount of cropland in acres as other biofuel feedstocks.