Using Electro Active Polymers to Transform Wave Energy Conversion

Abstract

The first generations of wave energy converters have had a number of forms, but all are essentially large steel structures concentrating the power take off onto small mechanical devices. A number of prototype devices have been installed offshore, but due to their high fabrication and installation costs, coupled with significant maintenance requirements, the production of electricity at an acceptable cost has remained elusive.To avoid the limitations of these devices, a second generation wave energy converter is being developed using electro active polymers (EAP), which are capable of generating electricity directly from wave action without the need for any mechanical power take off. The resulting system is flexible and possesses an infinite number of degrees of freedom, allowing wave energy to be captured more efficiently than with conventional devices. Deployed offshore, such a device would have no complex mechanical parts, would function silently, and would require minimal maintenance. The economics of such a system lead to predictions of a cost of electricity significantly below the levels of the first generation devices.The paper explains the principals involved in using EAP for the generation of electricity, the application of EAP to wave energy conversion, and reports key results from the ongoing development program. The paper also describes the main features of the prototype wave energy converter system presently under development for deployment offshore. An overview of the Renewable Energy marketRenewable energies have become inevitable in the energy mix. Over the last 15 years renewables have evolved from a marginal, politically correct, alternative vision to a credible energy source and a booming economic sector.In 2013, for the first time in centuries, newly installed power generation capacity from renewables was higher than that of conventional energy, including coal, gas and oil combined. In 2015 the difference became even larger and the trend is not expected to change, as shown in Figure 1.The falling costs of energy from renewables and aggressive expansion in emerging countries are the main drivers for the fast growth of renewable energy. Wind and Solar energy in particular have already reached grid parity in many countries, meaning that they are produced, without subsidies, at a cost lower than the local electricity retail price.

Electro‐Thermal model of thermal breakdown in multilayered dielectric elastomers

“…The lowest value of N BD obtained in the results shown in Figure is N BD = 904 at T 0 = 318K, E = 100V/ μ m, and with thermal insulation on the cylindrical surface. However, this amount of layers is far beyond the amount currently seen in any applications; for example, SBM Offshore has built a wave energy harvester with a maximum number of 300 layers …”

“…Dielectric elastomers (DEs) are promising materials for use in various electromechanical applications as actuators, sensors, and generators . Applications have a wide spectrum of sizes, ranging from microfluidic pumps over mm‐sized Braille displays through envisioned wave energy converters consisting of 400 m‐long tubes …”

Electro‐thermal and ‐mechanical model of thermal breakdown in multilayered dielectric elastomers

“…In recent decades, interest in and research into dielectric elastomers (DEs) have increased dramatically, due to the possibilities of an electromechanical transducer being used both as an actuator, a sensor, and a generator [1][2][3] . DEs can be used for a wide range of applications, such as artificial muscles [4][5][6][7] , wave energy harvesters 8,9 , and Braille displays 10,11 .…”