Fundamentals of Ocean Renewable Energy

Generating Electricity from the Sea

Simon P. Neill, M Reza Hashemi

• Publisher: Academic Press
• Year: 2018
• ISBN:
  9780128104491
• Topic: Technik & Maschinenbau
• Subtopic: Regenerative Energieressourcen

Fundamentals of Ocean Renewable Energy: Generating Electricity from the Sea presents the basic concepts of mechanics and introduces the various technical aspects of ocean renewable energy. Contents follow a logical sequence, starting with hydrodynamics and then separately examining each conversion technology, with special focus on tidal energy, offshore wind and wave energy, as well as current and ocean thermal energy conversion (OTEC). The authors explore key topics for resource characterization and optimization, such as monitoring and measurement methods and ocean modeling. They also discuss the sustainability, planning, integration and distribution challenges for the implementation of these technologies, including co-location with other systems.

Finally, case studies of ocean energy sites and devices allow for a better understanding of how ocean energy conversion works in real-world settings. This book is an invaluable resource for students at graduate and senior undergraduate level engineering (ocean, mechanical, and civil) and oceanography with prior knowledge of fluid mechanics and mechanics of materials.

• Presents the fundamental physics and theory behind ocean energy systems, covering both oceanographic and engineering aspects of ocean energy
• Explores the most widely adopted conversion technologies, including tidal, wave, offshore wind, ocean thermal and currents

Chapter 1

Introduction

Abstract

There has been a considerable increase in global electricity consumption over the last few decades, yet with vast differences between countries and regions. In addition, the global energy mix has changed significantly over time—the world still relies on coal for over 40% of its electricity generation, but the amount of electricity that is generated from renewable sources has risen rapidly over the last decade. In this chapter, we introduce the global energy mix and demonstrate how electricity consumption per capita is linked to quality of life. We discuss the pressures of climate change, and dwindling fossil fuel reserves, and how these two issues are driving the transition towards low carbon renewable sources of energy. However, renewable energy generation presents a challenge to electrical grid systems, and we discuss the challenges of accommodating a high penetration of renewable energy into existing grid infrastructure. Finally, we introduce the topic of marine energy, and the fundamental concepts of energy and power.

Keywords

Global energy mix; Climate change; Sea-level rise; Fossil fuel reserves; Electrical grid systems; Levelised cost of energy; Energy and power; Capacity factor

There has been a considerable increase in global electricity consumption over the last few decades, yet with vast differences between countries and regions. In addition, the global energy mix has changed significantly over time—the world still relies on coal for over 40% of its electricity generation, but the amount of electricity that is generated from renewable sources has risen rapidly over the last decade.

In this chapter, we introduce the global energy mix and demonstrate how electricity consumption per capita is linked to quality of life. We discuss the pressures of climate change, and dwindling fossil fuel reserves, and how these two issues are driving the transition towards low carbon renewable sources of energy. However, renewable energy generation presents a challenge to electrical grid systems, and we discuss the challenges of accommodating a high penetration of renewable energy into existing grid infrastructure. Finally, we introduce the topic of marine energy and the fundamental concepts of energy and power.

1.1 The Global Energy Mix

Global electricity production was 23,950 TWh in 2015 (Fig. 1.1), which, with a world population of 7.35 billion, translates as an annual power output of 3.3 MWh per capita (Fig. 1.2). Electricity generation has doubled since 1990, when global production was 11,854 TWh, representing an annual power output of 2.3 MWh per capita.¹ Energy consumption is one of the most accurate indicators of wealth, and so more affluent countries will generally have a higher electric power consumption per capita (Table 1.1). For example, it is fairly striking to note from this table that the United States, with an electricity usage of 12,988 kWh per capita in 2013, has 17 times the electricity consumption (per capita) as India (765 kWh per capita). The Human Development Index (HDI) is a summary measure of average achievement in key dimensions of human development: a long and healthy life, being knowledgeable, and having a good standard of living [1]. The HDI is the geometric mean of normalized indices for each of the three dimensions. The trend of electricity consumption per capita against HDI is very clear (Fig. 1.3). Noting that the x-axis in this figure is logarithmic, Norway tops Iceland (in contrast to Table 1.1) for HDI, despite having almost half of the electricity consumption per capita, but observe that the relationship of electricity consumption per capita between the United States and India is reflected in the HDI.

Fig. 1.1 Global electricity production, 1990–2015. (Data from the International Energy Agency, Key World Energy Statistics, 2016.)

Fig. 1.2 Global electricity consumption per capita, 1990–2015.

Table 1.1

Electric Power Consumption per Capita in 2013 for Selected Countries

Country	kWh per Capita
Iceland	54,799
Norway	23,326
Canada	15,519
Qatar	15,471
Sweden	13,870
United States	12,988
United Arab Emirates	10,904
Australia	10,134
Saudi Arabia	8741
Japan	7836
France	7374
Russia	6539
Ireland	5702
United Kingdom	5407
Spain	5401
Chile	3879
China	3762
Iran	2899
Brazil	2529
Mexico	2057
Costa Rica	1955
Peru	1270
Indonesia	788
India	765
Pakistan	450
Bangladesh	293
Sudan	159
Nigeria	142
Ethiopia	65
Niger	49
South Sudan	39

Source: Data from the World Bank (www.worldbank.org)

Fig. 1.3 Electricity consumption per capita per country plotted against Human Development Index (HDI) in 2013. (Electricity data from the World Bank, and HDI data from the United Nations Development Programme.)

Take a look at the image of Earth’s city lights in Fig. 1.4, based on satellite data processed by NASA....