MARINE MAIN ENGINE

Marine Main Engine The marine main engine is the heart of a ship’s propulsion system. It is the largest and most powerful machine on board, designed to convert fuel into mechanical energy that turns the propeller and drives the vessel forward. Without it, modern shipping—responsible for carrying around 90% of the world’s trade—would not be possible. Understanding the main engine is essential for students, seafarers, and anyone interested in marine engineering. Meaning and Purpose The main engine refers to the primary source of propulsion power in a ship. Its purpose is straightforward yet vital: to provide continuous, reliable thrust to move the vessel safely across oceans. Unlike auxiliary engines, which generate electrical power for onboard systems, the main engine directly powers the propeller shaft. This distinction highlights its role as the core machinery that ensures a ship’s mobility and operational efficiency. Background Marine engines have evolved significantly since the early days of steam propulsion. In the 19th century, ships relied on coal-fired steam engines. Over time, these were replaced by more efficient internal combustion engines. Today, the most common propulsion system in large commercial vessels is the two-stroke low-speed diesel engine, valued for its efficiency, durability, and ability to burn heavy fuel oil. However, with increasing environmental regulations, new technologies and alternative fuels are reshaping the future of marine propulsion.

UNCLOS WATERS

The United Nations Convention on the Law of the Sea (UNCLOS) stands as one of the most important international agreements in maritime history, providing a comprehensive framework that governs the rights, responsibilities, and conduct of nations in their use of the world’s oceans. Adopted in 1982 in Montego Bay, Jamaica, and entered into force in 1994, UNCLOS has since become the “constitution of the oceans,” shaping the global maritime order and ensuring stability in international waters. Today, more than 160 countries, including the Philippines, are parties to this convention, making it one of the most widely recognized treaties in modern international law. At its core, UNCLOS defines the extent of maritime zones, granting coastal states sovereign rights and jurisdiction over certain areas of the seas while maintaining the principle of freedom of navigation. The convention establishes baseline measurements from which maritime zones are determined, ranging from internal waters, territorial seas, and contiguous zones, to exclusive economic zones (EEZs) and continental shelves. These zones outline the rights of coastal states to exploit resources, regulate activities, and protect their environment, while balancing the rights of other states to access international waters. The territorial sea, extending up to 12 nautical miles from the baseline, grants full sovereignty to coastal states, similar to their land territory, albeit with the obligation to allow innocent passage for foreign vessels. Beyond this lies the contiguous zone, extending up to 24 nautical miles, where states can enforce customs, fiscal, and immigration regulations. However, it is the 200-nautical-mile Exclusive Economic Zone that has arguably had the most profound impact, as it allows coastal states exclusive rights to exploit and manage natural resources, including fisheries and energy reserves. UNCLOS also addresses the rights of landlocked states by ensuring access to the seas through transit routes and cooperation with neighboring states. By codifying these provisions, the convention promotes equity among nations and prevents maritime access from becoming a privilege limited only to coastal countries. Furthermore, it establishes rules on the exploitation of the deep seabed beyond national jurisdiction, declaring it the “common heritage of mankind” and mandating that its resources be managed for the benefit of all humanity. An important element of UNCLOS is its contribution to environmental protection. The convention obligates states to prevent, reduce, and control pollution of the marine environment, whether from ships, land-based sources, or dumping. It also encourages cooperation in scientific research, preservation of rare ecosystems, and sustainable use of marine living resources. These provisions reflect the recognition that the oceans are interconnected and that environmental harm in one region can have ripple effects across the globe. UNCLOS has also proven essential in resolving disputes among states. It provides mechanisms for peaceful settlement through negotiation, arbitration, or adjudication by bodies such as the International Tribunal for the Law of the Sea (ITLOS). These mechanisms ensure that maritime disputes, whether over boundary delimitations or navigational rights, are settled according to international law rather than unilateral action or force, thereby reducing the risk of conflict. The convention further enshrines the principle of freedom of navigation and overflight, vital for global trade and security. Given that around 90% of world trade is transported by sea, these provisions protect the lifeblood of the global economy. Naval operations, commercial shipping, and international aviation all rely on the stability and predictability created by UNCLOS, underscoring its role not only as a legal framework but also as a safeguard of global commerce. Over time, UNCLOS has adapted to contemporary challenges. Issues such as maritime security, piracy, illegal fishing, and marine biodiversity beyond national jurisdiction have required new interpretations and agreements supplementary to the convention. Despite criticisms that it cannot fully address emerging issues like climate change and rising sea levels, its framework remains the backbone of modern maritime governance. For countries like the Philippines, UNCLOS is particularly significant, as it provides the legal basis for asserting rights over maritime zones and resources. The 2016 arbitral ruling on the South China Sea dispute, rooted in UNCLOS provisions, reinforced the importance of the convention as a peaceful tool for resolving maritime conflicts, affirming that international law remains the strongest shield of smaller states against larger powers. In sum, UNCLOS has become indispensable in maintaining order in the world’s oceans. It balances the interests of coastal and landlocked states, safeguards navigation rights, promot

EMERGENCY GENERATOR

Ship Emergency Generator: Essential Safety Power at Sea On board a ship, electricity powers almost every operation from navigation and communication systems to lighting, pumps, and emergency alarms. When the main power supply fails, the safety of the vessel, its crew, and cargo relies on a reliable backup source. This is where the ship’s emergency generator becomes indispensable. Mandated by the International Convention for the Safety of Life at Sea (SOLAS), the emergency generator is a critical piece of equipment designed to supply electrical power to essential systems during emergencies. Background and Purpose The emergency generator serves as the ship’s lifeline during power loss or blackout. It automatically starts and transfers load to an emergency switchboard to ensure that key systems remain operational. Its purpose is not to run the entire ship but to sustain safety and emergency functions until the main power supply can be restored or the ship is brought to safety. The generator powers essential equipment such as emergency lighting in accommodation spaces, machinery areas, lifeboat embarkation points, and escape routes. It also supplies energy to fire detection and alarm systems, communication equipment, navigation instruments like radar and GPS, and in some cases, the steering gear. Pumps for fire-fighting and bilge operations, as well as emergency batteries and chargers, also depend on this backup system. Location and Construction To maximize reliability, the emergency generator is installed in a separate compartment from the main engine room—typically on an upper deck with its own ventilation, fire protection, and access. This arrangement prevents the generator from being compromised by incidents in the engine room. Most are diesel-driven alternators chosen for their rapid start-up capability and rugged design. They have independent fuel tanks, cooling systems, and starting mechanisms to ensure operation even if the main systems fail.

MARPOL 73/78 CONVENTION: LATEST UPDATES

The International Convention for the Prevention of Pollution from Ships, 1973, as modified by the Protocol of 1978, more commonly referred to as MARPOL 73/78, is the primary international agreement developed by the International Maritime Organization to prevent pollution of the marine environment from ships. Adopted in response to growing concern over oil spills and vessel discharges in the 1970s, it has since evolved into a comprehensive framework that addresses multiple forms of ship-source pollution. Together with SOLAS, MARPOL is regarded as one of the twin pillars of international maritime law, protecting both human life and the natural environment. MARPOL applies to all ships, though its requirements vary depending on size, type, and operation. Compliance is ensured through certification by flag states, enforcement by port state control, and the application of special provisions for designated “special areas” and “emission control areas” where stricter rules apply. Over the years, the Convention has grown through six technical annexes, each dedicated to a specific category of pollution. These annexes are the foundation of MARPOL and remain central to its implementation. Annex I addresses the prevention of pollution by oil. It includes requirements for double-hulled oil tankers, oil discharge monitoring and control systems, oily water separators, and record books. It is one of the most detailed annexes, reflecting the seriousness of oil pollution incidents. Annex II concerns the control of pollution by noxious liquid substances carried in bulk. It establishes categories for chemicals, prewash procedures, and restrictions on discharges, requiring chemical tankers to operate under strict safety and environmental standards. Annex III regulates the prevention of pollution by harmful substances carried by sea in packaged form. It is closely linked to the International Maritime Dangerous Goods (IMDG) Code, ensuring labeling, packaging, and documentation are standardized. Annex IV covers the prevention of pollution by sewage from ships. It requires ships to install approved sewage treatment plants or holding systems and regulates discharges into the sea, particularly in designated sensitive areas. Annex V deals with the prevention of pollution by garbage from ships. It prohibits the discharge of plastics, restricts the disposal of other wastes, and requires vessels to maintain garbage management plans and record books. This annex has been strengthened repeatedly to reflect the global urgency of reducing marine litter. Annex VI addresses the prevention of air pollution from ships. It limits emissions of sulfur oxides (SOx) and nitrogen oxides (NOx), regulates fuel oil quality, prohibits ozone-depleting substances, and introduces greenhouse gas reduction measures such as the Energy Efficiency Design Index (EEDI), Ship Energy Efficiency Management Plan (SEEMP), and the Carbon Intensity Indicator (CII). It also establishes Emission Control Areas where more stringent standards apply. Recent amendments highlight MARPOL’s responsiveness to modern environmental challenges. In 2024, Annex I was updated to require improved oil discharge monitoring equipment, while Annex II introduced expanded prewash obligations in the Baltic and North Sea to reduce chemical residues. Annex IV tightened sewage effluent standards, and Annex V expanded garbage management requirements to smaller ships and reinforced prohibitions on plastics. Annex VI amendments in 2024 introduced stricter nitrogen oxide limits for new engines and strengthened rules for ships using alternative fuels, ensuring adequate fire protection and fuel distribution systems in parallel with the IGF Code. By 2025, MARPOL continues to advance global decarbonization and environmental protection objectives. Annex VI now mandates enhanced monitoring and verification of the Carbon Intensity Indicator, requiring ships to achieve satisfactory efficiency ratings or adopt corrective action plans. This step places greater responsibility on shipping companies to reduce operational emissions. Electronic record books for oil, garbage, and cargo handling operations are increasingly being accepted in place of paper logs, reflecting the shift toward digital compliance and reducing administrative burdens. New reporting obligations for lost containers at sea, coordinated with parallel SOLAS amendments, will also apply from 2026, ensuring faster notification to authorities and minimizing environmental and navigational hazards. Annex III, through updates aligned with the IMDG Code, further enhances labeling and documentation for harmful substances in packaged form. These updates underline MARPOL’s role as a living instrument that evolves in response to both long-standing pollution risks and emerging challenges such as climate change, marine litter, and the transition to alternative fuels. The integration of greenhouse gas measures under Annex VI,