Posts Tagged ‘Renewable’

Management of Renewable Energies and Environmental Protection, Part II

March 13th, 2023

Abstract: The purpose of this project is to present an overview of renewable energy sources,Guest Posting major technological developments and case studies, accompanied by applicable examples of the use of sources. Renewable energy is the energy that comes from natural resources: The wind, sunlight, rain, sea waves, tides, geothermal heat, regenerated naturally, automatically. Greenhouse gas emissions pose a serious threat to climate change, with potentially disastrous effects on humanity. The use of Renewable Energy Sources (RES) together with improved Energy Efficiency (EE) can contribute to reducing energy consumption, reducing greenhouse gas emissions and, as a consequence, preventing dangerous climate change. At least one-third of global energy must come from different renewable sources by 2050: The wind, solar, geothermal, hydroelectric, tidal, wave, biomass, etc. Oil and natural gas, classical sources of energy, have fluctuating developments on the international market. A second significant aspect is given by the increasingly limited nature of oil resources. It seems that this energy source will be exhausted in about 50 years from the consumption of oil reserves in exploitation or prospecting. “Green” energy is at the fingertips of both economic operators and individuals. In fact, an economic operator can use such a system for both own consumption and energy trading on the domestic energy market. The high cost of deploying these systems is generally depreciated in about 5-10 years, depending on the installed production capacity. The “sustainability” condition is met when projects based on renewable energy have a negative CO2 or at least neutral CO2 over the life cycle. Emissions of Greenhouse Gases (GHG) are one of the environmental criteria included in a sustainability analysis, but is not enough. The concept of sustainability must also include in the assessment various other aspects, such as environmental, cultural, health, but must also integrate economic aspects. Renewable energy generation in a sustainable way is a challenge that requires compliance with national and international regulations. Energy independence can be achieved: – Large scale (for communities); – small-scale (for individual houses, vacation homes or cabins without electrical connection).

Keywords: Environmental Protection, Renewable Energy, Sustainable Energy, The Wind, Sunlight, Rain, Sea Waves, Tides, Geothermal Heat, Regenerated Naturally.

Introduction

The purpose of this project is to present an overview of renewable energy sources, major technological developments and case studies, accompanied by applicable examples of the use of sources.

Renewable energy is the energy that comes from natural resources: The wind, sunlight, rain, sea waves, tides, geothermal heat, regenerated naturally, automatically.

Greenhouse gas emissions pose a serious threat to climate change, with potentially disastrous effects on humanity. The use of Renewable Energy Sources (RES) together with improved Energy Efficiency (EE) can contribute to reducing energy consumption, reducing greenhouse gas emissions and, as a consequence, preventing dangerous climate change.

At least one-third of global energy must come from different renewable sources by 2050: The wind, solar, geothermal, hydroelectric, tidal, wave, biomass, etc.

Oil and natural gas, classical sources of energy, have fluctuating developments on the international market. A second significant aspect is given by the increasingly limited nature of oil resources. It seems that this energy source will be exhausted in about 50 years from the consumption of oil reserves in exploitation or prospecting.

“Green” energy is at the fingertips of both economic operators and individuals.

In fact, an economic operator can use such a system for both own consumption and energy trading on the domestic energy market. The high cost of deploying these systems is generally depreciated in about 5-10 years, depending on the installed production capacity.

The “sustainability” condition is met when projects based on renewable energy have a negative CO2 or at least neutral CO2 over the life cycle.

Emissions of Greenhouse Gases (GHG) are one of the environmental criteria included in a sustainability analysis, but is not enough. The concept of sustainability must also include in the assessment various other aspects, such as environmental, cultural, health, but must also integrate economic aspects.

Renewable energy generation in a sustainable way is a challenge that requires compliance with national and international regulations.

Energy independence can be achieved:

Large scale (for communities)
Small-scale (for individual houses, vacation homes or cabins without electrical connection)
Today, the renewable energy has gained an avant-garde and a great development also thanks to governments and international organizations that have finally begun to understand its imperative necessity for humanity, to avoid crises and wars, to maintain a modern life (we can’t go back to caves).

Materials and Methods

The Micro-Hydropower Potential

Hydroelectric power comes from the action of moving water. It can be seen as a form of solar energy because the sun feeds the water circuit in nature. Within this circuit, the water from the atmosphere reaches the surface of the earth in the form of precipitation. Part of it evaporates, but much of it penetrates the soil or becomes flowing water to the surface. Rainwater and melted snow finally end up in ponds, lakes, reservoirs or oceans where evaporation takes place permanently.

Water resources due to inland rivers are estimated at about 42 billion cubic meters per year, but under unchecked storage, it can only account for about 19 million cubic meters per year due to fluctuations in river flows.

Low-power hydropower plants are a major contributor of renewable electricity at European and world level. Worldwide, it is estimated that there is an installed capacity of 47,000 MW, with a potential – technical and economic – close to 180,000 MW.

Low-Power Hydropower Plants (HMP) are powered by natural water flow, i.e., it does not involve large-scale water capture and therefore does not require the construction of large dams and reservoirs, although they help where they exist and can be used easily. There is no international definition of the HMP and the upper limit varies between 2.5 and 25 MW depending on the country, but the 10 MW value is generally accepted and promoted by European Association of Low Power Hydro Power Plants (ESHA).

Low power plants are one of the most reliable and cost-effective technologies for producing clean electricity.

In particular, the key advantages of HMPs to wind-based, wave-based or solar power plants are:

High efficiency (70-90%), by far the best of all energy technologies
A high capacity factor (usually> 50%), compared to 10% for solar energy and 30% for wind power
High predictability, depending on yearly rainfall patterns
Low rate of variability; The energy produced varies only gradually from day to day (not from one minute to the next)
Good correlation with demand (eg output is maximum in winter)
It is a sustainable and solid technology; Systems can be designed to work for over 50 years
HMPs are also environmentally friendly. Most of the time, they work on the natural course of water. Therefore, this type of water-based installation does not have the same negative environmental effects as large hydropower plants.

Small hydropower plants can be located either in mountainous areas where rivers are fast or in low-lying areas with large rivers. The four most common types of micro-power plants are presented below.

For large and medium fall schemes, channel and duct combinations are used. If the terrain is injured, the construction of the canal is difficult and then only the forced duct that can sometimes be buried is used. In the barrage arrangements the turbines are placed in or in the immediate vicinity of the dam, so that there is almost no need for the channel or the pipeline.

Another option of placing the microturbines is to use the flows from the water treatment plants.

The objective of a hydroelectric system is to convert the potential energy of the volume of water flowing from a certain height into electricity at the bottom end of the system where the power plant is located. The water level difference, known as “fall”, is essential for the production of hydroelectricity; The simple rapid flow of water does not contain enough energy to produce significant electrical energy than on a very large scale such as coastal submarine currents. That is why two indicators are needed: Q water flow and H dropping. It is generally better to have a larger drop than a higher flow, because smaller equipment can be used.

Grossfall (H) is the maximum vertical distance between upstream and downstream water levels. The actual fall seen at the turbine will be somewhat lower than the gross fall, due to the loss of water in and out of the system. This low fall is called the Net Fall.

Flow rate (Q) is the volume of water passing into the unit of time, measured in m3/s. For small systems, the flow rate can also be expressed in liters/second, where 1000 l/s = 1 m3/sec. Depending on the fall, hydroelectric plants can be classified into three categories: