Power Electronics Converters for Renewable Energy (EX-803 (A)) - Unit 2 Short Notes

UNIT 2: Environmental Issues, Policies, Standards & Renewable Energy Sources

I. Environmental Concerns & Climate Change

Global Environmental Concerns

Major concerns include:

• Air pollution (smog, acid rain)

• Water pollution & scarcity

• Soil degradation & desertification

• Ozone layer depletion

• Climate Change (global warming)

• Loss of biodiversity

• Deforestation

• Municipal solid waste management

Atmospheric Changes & Climate Change
Factors Responsible:

• Greenhouse Gas (GHG) Emissions: CO₂ (fossil fuels), CH₄ (agriculture, waste), N₂O (fertilizers)

• Deforestation: Reduces CO₂ absorption

• Industrialization & Urbanization: Increases emissions

• Land Use Changes: Alter carbon cycles

Predicting Future Trends:

• Climate models project:

  • Rising global temperatures (1.5°C–4°C by 2100)

  • Sea-level rise (0.3–1 m)

  • Extreme weather events (floods, droughts)

  • Glacial retreat & Arctic ice melt

[!TIP] IPCC assessment reports (AR6, 2021–2023) are primary sources for climate projections.

Role of IPCC

• Established by UNEP & WMO (1988)

• Provides scientific assessments on climate change, impacts, and mitigation

• Publishes Assessment Reports (AR6 is latest)

• Informs international climate negotiations (e.g., UNFCCC, Paris Agreement)

• Does not conduct original research; reviews published literature

II. International Environmental Policies & Agreements

Earth Summit (Rio de Janeiro, 1992)

• Significance:

  • First major UN conference on environment & development

  • Adopted Agenda 21 (action plan for sustainable development)

  • Laid foundation for UNFCCC (climate change), CBD (biodiversity)

  • Introduced principle of "Common but Differentiated Responsibilities"

Kyoto Protocol (1997)

• Purpose: Legally binding emission reduction targets for developed countries (Annex I parties) during 2008–2012.

• Mechanisms: Emissions Trading, Clean Development Mechanism (CDM), Joint Implementation.

• Limitations:

  • No binding targets for developing countries (e.g., India, China)

  • US never ratified; Canada withdrew

  • Limited coverage of global emissions (~18% in first commitment period)

  • No penalty for non-compliance

Clean Development Mechanism (CDM)

• Allows developed countries to invest in emission-reduction projects in developing countries.

• Earns Certified Emission Reductions (CERs) credits toward Kyoto targets.

• Promotes sustainable development in host countries.

Prototype Carbon Fund (PCF)

• World Bank’s first carbon fund (established 2000).

• Invests in projects that reduce GHG emissions in developing/transition economies.

• Generates carbon credits for investors.

Global Program for Protected Area Management

• Joint initiative by IUCN, WWF, UNEP.

• Aims to strengthen management effectiveness of protected areas worldwide.

• Focuses on capacity building, funding, and governance.

III. Environmental Standards & Regulations

ISO 14000 Series

• Components: ISO 14001 (EMS standards), ISO 14004 (guidelines), ISO 14010–14031 (auditing/life cycle assessment), ISO 14040/44 (LCA).

• Purpose: Provide framework for Environmental Management Systems (EMS) to improve environmental performance, ensure compliance, and achieve continual improvement.

• Basic Features:

  • Plan-Do-Check-Act (PDCA) cycle

  • Legal compliance focus

  • Documentation & record keeping

  • Third-party certification possible

  • Non-prescriptive (organizations set own targets)

Air (Prevention & Control of Pollution) Act, 1981

• Salient Features:

  • Empowers Central & State Pollution Control Boards to set air quality standards.

  • Requires consent for establishing/operating industries.

  • Defines "air pollutant" as any solid, liquid, or gaseous substance present in atmosphere in concentration harmful to environment/human health.

  • Provides for emission standards from vehicles & industries.

Water (Prevention & Control of Pollution) Act, 1974

• Definition of Pollution (Sec. 2(e)):

  "Such contamination of water... or such alteration of the physical, chemical or biological properties of water... as is likely to cause a hazard to public health or safety, or to domestic, commercial, industrial, agricultural or other legitimate uses, or to the life and health of animals or plants or of aquatic organisms."

• Salient Features:

  • Establishes Central & State Pollution Control Boards.

  • Consent mechanism for discharge of effluents.

  • Power to take samples and analyze.

  • Penalties for violations (imprisonment/fine).

Minimal National Standards (MINAS)

• Industry-specific effluent & emission standards notified under Environment (Protection) Act, 1986.

• Based on best available technology economically achievable.

• Examples: Standards for textile, pulp & paper, fertilizer industries.

Wastewater Effluent Standards

• Governed by CPCB under Environment (Protection) Rules, 1986.

• Key parameters: BOD ≤ 30 mg/L, COD ≤ 250 mg/L, pH 6.0–9.0, TSS ≤ 100 mg/L for discharge into surface water (general standards).

• More stringent for sensitive areas (e.g., drinking water sources).

Municipal Solid Waste (Management & Handling) Rules, 1998

• Salient Features:

  • Source reduction & segregation (biodegradable/non-biodegradable).

  • Collection, transportation, processing (composting, waste-to-energy).

  • Landfilling as last resort with liners & leachate treatment.

  • State Pollution Control Boards monitor compliance.

State Environment Policies (e.g., M.P. State Environment Policy)

• Align with National Environment Policy but address state-specific issues (e.g., forest cover, river pollution, mining impacts).

• Emphasize community participation, EIA, and pollution control.

IV. Environmental Regulatory Bodies & Functions

United Nations Environment Programme (UNEP)

• Functions:

  • Coordinates global environmental governance.

  • Provides scientific assessments (e.g., Global Environment Outlook reports).

  • Facilitates international environmental agreements.

  • Promotes environmental capacity building in developing countries.

  • Addresses emerging issues (e.g., climate change, biodiversity loss).

Central Pollution Control Board (CPCB)

• Functions:

  • Sets national standards for air/water quality & emissions.

  • Monitors pollution levels across India.

  • Advises MoEFCC on policy matters.

  • Coordinates activities of State Pollution Control Boards (SPCBs).

  • Implements pollution control programs (e.g., National River Conservation Plan).

• Pollution Control Measures (Case Study Example):

  • Ganga Action Plan: Sewage treatment plants, electric crematoria, riverfront development.

  • Air Quality Management in Delhi: Odd-even vehicle scheme, switch to CNG, Graded Response Action Plan (GRAP).

  • Industrial Pollution: Mandatory Effluent Treatment Plants (ETPs), Common Effluent Treatment Plants (CETPs).

Intergovernmental Panel on Climate Change (IPCC)

• Brief Details:

  • Parent Organizations: UNEP & WMO.

  • Structure: Three Working Groups (I: Physical Science; II: Impacts/Adaptation; III: Mitigation) + Task Forces.

  • Outputs: Assessment Reports, Special Reports, Methodology Reports.

  • Nobel Peace Prize 2007 (shared with Al Gore).

V. Renewable Energy Sources (Non-conventional)

Types of Non-conventional Energy Sources

1. Solar Energy

2. Wind Energy

3. Tidal Energy

4. Wave Energy

5. Geothermal Energy

6. Biomass & Biogas

7. Hydrogen Energy

8. Ocean Thermal Energy Conversion (OTEC)

Solar Energy

• Solar Cells (Photovoltaic Cells):

  • Diagram:

    DiagramSEARCH: photovoltaic cell diagram p-n junction

    • Basic structure: p-n junction semiconductor (silicon).

    • Sunlight → electron-hole pair generation → current flow.

  • Applications:

    • Rural electrification (solar home systems)

    • Solar water pumps

    • Solar street lighting

    • Grid-connected rooftop systems

    • Space satellites & calculators

Wind Energy

• Advantages:

  • Clean (no GHG emissions during operation)

  • Renewable & inexhaustible

  • Low operating cost

  • Land under turbines can be used for agriculture

• Merits & Demerits:

  | Merits | Demerits | |-------------------------------------|---------------------------------------| | Zero fuel cost | Intermittent (wind-dependent) | | Low maintenance | Noise pollution | | Scalable (small to large farms) | Visual impact (landscape) | | Creates jobs (manufacturing, O&M) | High initial capital cost | | | Threat to birds/bats |

Tidal Energy

• Problems in Exploitation:

  • High capital cost (barrages, turbines)

  • Limited sites (high tidal range required)

  • Environmental impact on marine ecosystems

  • Corrosion & bio-fouling of equipment

  • Intermittency (depends on tidal cycles)

Biogas Energy

• Produced by anaerobic digestion of organic waste (cattle dung, agricultural residue, sewage).

• Composition: ~60% CH₄, 40% CO₂.

• Uses: Cooking, electricity generation, vehicle fuel (after purification).

• Advantages: Waste disposal + energy, manure byproduct, reduces deforestation.

Comparative Analysis: Solar vs. Biogas Energy

VI. Sustainable Development & Strategies

Concept & Definition

Sustainable Development: "Development that meets the needs of the present without compromising the ability of future generations to meet their own needs." – Brundtland Commission (1987).

Strategies for Environmental Improvement & Sustainable Development

1. Renewable Energy Promotion (solar, wind, biogas subsidies)

2. Energy Efficiency (LEDs, efficient appliances, industrial audits)

3. Waste Minimization & Recycling (circular economy)

4. Afforestation & Biodiversity Conservation

5. Sustainable Agriculture (organic farming, water conservation)

6. Eco-friendly Transportation (EVs, public transport)

7. Environmental Education & Awareness

8. Strict Enforcement of environmental laws

9. Green Infrastructure (rainwater harvesting, green buildings)

Green Certificates

• Tradable certificates representing renewable energy generation (e.g., Renewable Energy Certificates (RECs) in India).

• Mechanism: Obligated entities (discoms, industries) must purchase RECs to meet Renewable Purchase Obligation (RPO).

• Promotes renewable energy without direct subsidies.

Water Quality Monitoring Plan for a Community

1. Baseline Survey: Identify contamination sources (sewage, industrial, agricultural runoff).

2. Parameter Selection: Physical (turbidity, temperature), Chemical (pH, BOD, heavy metals), Biological (coliforms).

3. Sampling Locations: Upstream/downstream, wells, taps, borewells.

4. Frequency: Monthly/quarterly based on risk.

5. Testing Labs: Use accredited labs or field test kits.

6. Data Analysis: Compare with BIS/WHO standards.

7. Community Involvement: Train locals for simple tests (e.g., arsenic test kits).

8. Reporting & Action: Notify authorities if standards exceeded; suggest remediation (e.g., chlorination, filtration).

VII. Water Quality Management

Physical Water Quality Parameters

• Temperature: Affects dissolved oxygen, metabolic rates.

• Color & Turbidity: Indicates suspended solids, algae.

• Odor: Organic pollution, industrial discharge.

• Taste: Dissolved salts, minerals.

• Total Dissolved Solids (TDS): Inorganic salts, organic matter.

Chemical Water Quality Parameters

• pH: Ideal 6.5–8.5; extreme values harm aquatic life.

• Hardness (Ca²⁺, Mg²⁺): Causes scaling; >500 mg/L undesirable.

• Dissolved Oxygen (DO): >5 mg/L for aquatic life; <2 mg/L indicates severe pollution.

• Biochemical Oxygen Demand (BOD): Organic matter load; <3 mg/L for drinking water.

• Chemical Oxygen Demand (COD): Total oxidizable matter; higher than BOD.

• Heavy Metals (Pb, Cd, Hg, As): Toxic even at low concentrations.

• Nitrates & Phosphates: Cause eutrophication.

• Chlorides & Sulphates: Corrosive at high levels.

• Sodium Absorption Ratio (SAR): Irrigation suitability.

VIII. Protected Areas & Biodiversity

Benefits of Protected Areas

• Biodiversity Conservation: Habitat for flora & fauna, genetic diversity.

• Ecosystem Services: Watershed protection, soil conservation, carbon sequestration.

• Climate Resilience: Buffers against extreme weather.

• Scientific Research & Education: Natural laboratories.

• Ecotourism & Livelihoods: Revenue for local communities.

• Cultural/Spiritual Values: Sacred groves, indigenous knowledge.

Protected Area Management

• Zonation: Core (strict protection), buffer (limited use), transition (sustainable use).

• Management Plans: Based on ecosystem approach, adaptive management.

• Community Involvement: Joint Forest Management (JFM), co-management.

• Monitoring: Biodiversity surveys, threat assessment (poaching, invasive species).

• Funding: Government grants, international funds (e.g., Global Environment Facility), eco-tourism revenue.

• Legal Framework: Under Wildlife (Protection) Act, 1972 (India); IUCN categories (I–VI).

IX. Integrated Case Studies & Applications

CPCB Pollution Control Measures – Case Study Analysis

• Case: Air Pollution in Delhi-NCR

  • Measures:

    1. Graded Response Action Plan (GRAP): Emergency measures (construction bans, odd-even scheme) during high pollution.

    2. Switch to Cleaner Fuels: CNG for public transport, PNG for industries.

    3. Vehicular Standards: BS-VI norms, scrappage policy.

    4. Industrial Shifts: Relocation of polluting industries, promotion of zig-zag kilns in brick industry.

    5. Stubble Burning: Subsidies for Happy Seeder machines, biomass conversion.

  • Outcome: PM₂.₅ levels reduced but still exceed standards; highlights need for regional coordination.

Development of Water Quality Monitoring Plans

• Example: Community Water Quality Plan for Rural Village

  1. Objective: Ensure safe drinking water (BIS standards).

  2. Parameters: Turbidity, pH, TDS, coliforms, arsenic (if endemic).

  3. Methodology:

     • Monthly sampling from 5 hand pumps & 2 wells.

     • Use H₂S vials for coliforms (simple field test).

     • Send quarterly samples to district lab for heavy metals.

  4. Remediation: Install biosand filters for turbidity; chlorination for disinfection; arsenic removal units if needed.

  5. Awareness: Train village water committee; display results publicly.

Application of ISO 14000 in Industry

• Implementation Steps:

  1. Environmental Policy commitment by top management.

  2. Aspect-Impact Assessment: Identify activities affecting environment (e.g., emissions, waste).

  3. Legal Compliance: Map applicable laws (Air/Water Acts, EIA notifications).

  4. Objectives & Targets: e.g., "Reduce water consumption by 20% in 2 years."

  5. Operational Control: SOPs for waste handling, chemical storage.

  6. Monitoring & Measurement: Track emissions, effluent quality.

  7. Internal Audit: Check EMS effectiveness.

  8. Management Review: Continuous improvement.

• Benefits:

  • Enhanced regulatory compliance (avoid penalties).

  • Resource efficiency (energy/water savings).

  • Improved public image & market access (green procurement).

  • Risk mitigation (accidents, spills).

[!TIP] In exams, link ISO 14000 to sustainable development and corporate social responsibility (CSR).