Harnessing Alternative Energy Sources for a Sustainable Future

Posted on Apr 4, 2025 in Geology

Alternative Energy

A. From the Sun (Renewable):
The big problem is that solar energy is widely dispersed and needs to be concentrated.

Architectural Systems Liabilities:
It’s possible to heat or cool a house using only sunlight. Planting trees near buildings can reduce air conditioning needs by 60%. Trees act as biological solar collectors, passively cooling buildings by providing shade and evaporating water, which cools the environment.

Solar Power Plants:
These are facilities where energy is obtained when the sun heats a liquid, which in turn produces energy (oil and water). Steps:
1. Focus the sun at one point using mirrors.
2. The light heats a liquid, including water.
3. The steam drives a turbine and generates energy.
Disadvantages: Impact on landscape and water usage.
Advantages: Reduces our dependence on oil and provides very clean energy.

Photovoltaic Solar Power:
This source turns sunlight directly into electricity by absorbing photons, which provides a stream of electrons, i.e., an electrical current. Each cell is made from monocrystalline silicon, making its manufacture very expensive.
Advantages: PV generates electricity with no pollution, no noise, and no moving parts. The facilities require minimal maintenance and no water. There is no impact on the landscape.
Cons: Space for installation (rooftops), visual impact, and variability in production.

Biomass Energy:
This source is derived from photosynthesis.
Advantages: It is a potentially renewable resource and has a zero balance of CO₂, absorbing the same amount it emits.
Disadvantages: Transport is expensive and economically inefficient. Biomass as an energy source has two modes of use: burned directly or processed into other fuels such as biogas and biofuels.

Biomass Energy Applications:
The more traditional use of biomass is the direct burning of wood for heating, water heating, and cooking. It is also used for electrical energy in biomass power plants that operate similarly to conventional ones but without fossil fuels.

• Biogas: Obtained by the anaerobic fermentation of organic waste.
• Biofuels:
  
  • Bioethanol: Obtained by alcoholic fermentation and subsequent distillation and dehydration of starchy vegetables such as potatoes, cereals, or sucrose. After a drying process, with increasing alcohol content, it becomes a fuel similar to gasoline, which can be mixed after making adjustments in motor vehicles. Advantages: It emits less CO₂ than gasoline.
    Disadvantages: It produces less energy, is only useful in hot countries, and may require engine adaptations.
  • Biodiesel: Produced from vegetable oils. After undergoing a methyl esterification process, the resulting liquid can be used alone in unrefined diesel engines that have been prepared for it, or after sophisticated chemical processing, can be used in any diesel engine mixed with other fossil fuels. This fuel drastically reduces CO₂ and other gaseous pollutants such as SO_x and particulate matter.
    Disadvantages: Increased NO_x emissions and changes in vehicle compatibility.

Social Debate Over the Use of Biofuels:
Biofuels have environmental drawbacks, including excessive water consumption, pesticide use, and fuel costs associated with moving farm machinery. Another issue arises from subsidies for food crops, which have led to biofuel crops replacing food crops. According to FAO reports, this has resulted in food price increases between 20% and 50%. For example, the price of meat in Argentina has tripled, and the price of corn in Mexico has risen significantly. Another major concern is the threat to biodiversity.

One possible solution is to avoid using biofuels for human consumption and instead focus on second-generation biofuels. The cultivation of algae for biodiesel production looks promising, as it can serve as a good sink for atmospheric CO₂, thereby reducing its concentration.

Wind Energy (Renewable):
Wind energy is harnessed through wind turbines.