Abstract
Distributed Embedded Energy Converter Technologies (DEEC-Tec) is a relatively new technology domain for marine renewable energy research. The domain shows significant promise for the advancement of innovative marine energy converter designs and presents promising opportunities to expand upon current possibilities for marine energy conversion. On the whole, DEEC-Tec is centered upon the aggregation of many small distributed embedded energy converters (DEECs) that, in turn, are incorporated to create metamaterials for the construction of larger energy harvesting and converting structures. When applied to ocean wave energy, these structures can be called flexWECs – a word blending the oft-compliant nature of DEEC-Tec based structures with that structure’s overarching purpose: to be an ocean wave energy converter (a WEC).
The DEEC-Tec domain enables several inherent advantages for ocean wave energy conversion. Some of these inherent advantages are: (i) broad-banded conversion of ocean wave frequencies; (ii) removing the need for large, highly loaded, rigid bodies; (iii) inherent redundancy; and (iv) eliminating force concentrations acting upon singular prime-movers and power transmission mechanisms. Indeed, a hallmark feature of any flexWEC is its ability to convert ocean wave energy throughout its entire structure – directly, in situ – thereby avoiding the accumulation of forces, pressures, loads, etc. onto (and into) centralized transmission systems (e.g., driveshafts); prime movers (e.g., a rotary generator); and/or power take-off systems (e.g., hydraulic piston-cylinder transfer systems). Of particular note, by being made of many small DEECs, flexWECs have innate built-in redundancy – even if some DEECs fail, an overall flexWEC’s operation could continue uninhibited via the numerous other DEECs available.
In whole, it is the aggregation of many small interconnected DEECs, which make up a flexWEC’s structure, that gives such promising potential for DEEC-Tec’s application in the field of marine renewable energy. Each individual DEEC consists of both a transducer and a structural mechanism. As a flexWEC's structure is being dynamically deformed by ocean wave energy, then those DEECs embodying that structure are also being dynamically deformed. That deformation can then be damped by the transducer mechanism of each individual DEEC. It is this damping – the energy being extracted from a DEEC’s ocean energy-induced deformations – that represents any flexWEC’s fundamental energy conversion process; the transformation of ocean wave energy into a more usable energy source such as electricity. Some examples of DEEC transducer mechanisms include (but are not limited to): MEMs generators, dielectric elastomer generators, hydraulically amplified self-healing electrostatic generators (HASELs), etc.
Ultimately, the successful development and application of DEEC-Tec into the field of marine renewable energy will require the advancement and combination of three main sub-technology groups: (i) small energy transducers (individual DEECs) that can convert dynamic deformation into desirable energy forms; (ii) DEEC-Tec metamaterials – pseudo-material frameworks via the integration of many DEECs; and (iii) flexWECs – structures constructed from the DEEC-Tec metamaterials and whose topology (shape) and morphology (flexibility) are designed for the explicit purpose of harvesting and converting ocean energy into more usable forms. Lastly, further developments of DEEC-Tec will require promotion of its potential along with creating greater awareness of its existence.