Sustainable Energy: Biomass, Marine Power, and Waste Management

Biomass Energy Production

Anaerobic Digestion

This process takes place by the action of certain bacteria in the absence of oxygen and at a temperature around 30 °C, converting biomass into biogas.

Biogas Composition and Use

Biogas consists mainly of methane ($ ext{CH}_4$) and $ ext{CO}_2$, and can be used in combustion engines.

Photoproduction of Fuel

Through the action of microorganisms on water and certain organic compounds, hydrogen can be obtained.

Advantages of Biomass Use

• Solves waste disposal problems.
• Prevents pollution.
• Reduces the risk of forest fires.
• Reduces consumption of fossil fuels and other non-renewable energy sources.

Drawbacks of Biomass Energy

• Excessive logging can deplete the plant biomass of a zone.
• Aquatic biomass is difficult to harness.
• The harvesting process requires energy, resulting in a very small net energy income, often making it unprofitable.
• The combustion process generates $ ext{CO}_2$.

Municipal Solid Waste (MSW)

Solid substances are those considered discarded or unusable and produced as a result of human activity.

Methods of MSW Management

1. Landfill
2. Composting
3. Incineration
4. Recycling

Landfill (Waste Storage)

A landfill is the storage of waste on the ground, covered periodically to prevent contaminant spillage. The operation can be controlled or uncontrolled. Uncontrolled dumping is highly damaging, causing pollution and negatively affecting the landscape.

Composting

Composting is the controlled fermentation of organic waste for use as fertilizer or, sometimes, to obtain biogas.

Incineration

Incineration involves burning combustible waste to produce thermal energy that can be used for heating or converted into other forms of energy.

Recycling

Recycling consists of reusing, as raw material, the part of the waste that has been previously classified.

Renewable Energy from the Sea

Tidal Energy

To harness tidal energy, a considerable amplitude is required. The most suitable locations are coasts near the continental shelf. Plants are typically installed on estuaries, consisting of a dam provided with gates that communicate between the sea and the coast to retain water at high tide. At low tide, the gates are opened, and the water drives a turbine connected to an alternator, which produces electrical energy.

Wave Power

The utilization of wave kinetic energy is difficult and costly due to the low performance of the transformation processes involved.

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