Electricity is central to modern professional environments across Kenya, powering everything from hospital equipment to banking systems and agricultural machinery. Understanding the sources of electricity and the principles behind its generation and storage is essential for professionals in all fields. This chapter explores the fundamental types of electricity sources and delves into the process of electrolysis, highlighting its practical applications in various sectors such as water treatment and metal recovery.

2.1 Sources of electricity

Electricity can be generated and supplied through various sources, each with unique characteristics affecting reliability, cost, and environmental impact. In Kenya, professionals encounter electricity from both conventional and renewable sources, which influence operational decisions in institutions like county government offices and universities.

2.1.1 Primary and secondary sources of electricity

Electricity sources are broadly categorized into primary and secondary types, reflecting how electricity is initially produced or stored.

Primary sources of electricity

• Fossil fuels: These include coal, oil, and natural gas, which are burned to generate electricity. Though less common in Kenya's electricity mix, they remain significant globally and affect institutions relying on national grid power.

• Hydropower: Generated by water flowing through turbines, hydropower is a major source in Kenya, supplying many county hospitals with stable electricity.

• Solar energy: Solar panels convert sunlight directly into electricity, increasingly used by schools in rural areas to ensure continuous power supply.
• Wind energy: Wind turbines generate electricity from air movement, a growing source in some Kenyan counties with favorable wind conditions.
• Geothermal energy: Utilizes heat from the earth’s interior to produce electricity, providing a renewable base load for urban centers like Nairobi.

Secondary sources of electricity

• Batteries: Store electrical energy chemically for later use, essential for backup power in retail businesses during outages.

• Capacitors: Store electrical energy temporarily in an electric field, used in electronic devices across various sectors.

• Cells: Single electrochemical units converting chemical energy into electrical energy, powering devices such as medical equipment in county referral hospitals.

2.1.2 Renewable and non-renewable sources

The distinction between renewable and non-renewable electricity sources impacts sustainability and long-term planning in professional environments.

Renewable sources

• Solar power: Renewable and abundant, solar energy supports off-grid power in agricultural cooperatives.
• Wind power: Sustainable and clean, it powers certain county government offices with minimal environmental footprint.
• Hydropower: Renewable but dependent on rainfall patterns, critical for universities relying on consistent electricity.
• Geothermal power: Provides continuous renewable energy, supporting industrial sectors in Kenya.
• Biomass energy: Derived from organic materials, used in some rural hotels for combined heat and power.

Non-renewable sources

• Fossil fuels: Finite and polluting, used in backup generators at banks and SACCOs during power failures.
• Nuclear energy: Not yet widely adopted in Kenya but a significant non-renewable source globally.
• Coal: Limited use in Kenya but important in some industrial power generation contexts.

2.1.3 Direct current (DC) and alternating current (AC) sources

Understanding the nature of electrical current is fundamental for professionals managing electrical devices and infrastructure.

Direct current (DC)

• Definition: Current flows in a single direction, typical of batteries and cells.
• Applications: Used in portable electronic devices in hospitals and retail businesses.
• Advantages: Stable voltage output, ideal for sensitive equipment.
• Limitations: Less efficient for long-distance transmission.
• Example: UPS systems in universities use DC batteries to provide emergency power.

Alternating current (AC)

• Definition: Current reverses direction periodically.
• Applications: Powers most buildings and industrial equipment, including county government offices.
• Advantages: Efficient for transmission over long distances.
• Limitations: Requires transformers to change voltage levels.
• Example: The national grid supplies AC power to banks and hotels.

2.1.4 Importance of understanding electricity sources in professional settings

Knowledge of electricity sources enables effective decision-making regarding energy use, cost management, and sustainability.

Operational efficiency

• Energy selection: Choosing appropriate power sources reduces operational costs in sectors like healthcare.
• Backup planning: Understanding battery systems ensures continuity in retail businesses during outages.
• Equipment compatibility: Matching devices with correct current types prevents damage in educational institutions.
• Sustainability goals: Integrating renewable sources aligns county offices with environmental policies.
• Risk management: Anticipating power source limitations minimizes disruptions in banking services.

Chapter Summary

This chapter explored various sources of electricity, highlighting their fundamental role in powering devices and systems. It examined the process of electrolysis and its practical applications in industries and technology. The concept of simple cells was introduced, explaining how chemical reactions generate electrical energy. The distinction between primary and secondary cells was clarified, emphasizing their differing capabilities for recharge and reuse. Various types of cells and batteries were described, including dry cells, Leclanché, mercury, lead-acid, alkaline, and lithium, each with unique characteristics and uses. The chapter also covered important electrical properties of cells such as electromotive force and internal resistance, which affect performance. Proper maintenance techniques for batteries were discussed to ensure longevity and efficiency. Lastly, the diverse applications of batteries in everyday and specialized equipment were outlined, demonstrating their essential role in modern electrical systems.