Ocean energy and ocean energy powerplant

[l-emele]

Description of the issue

Split from #78: We need to define something like ocean energy and ocean energy powerplant.

Ideas of solution

Idea from #78:

• OceanPowerplant: An OceanPowerplant is a HydroPowerplant that is a powerplant using the oceans motion to create electric energy.

Preliminary results

Marine thermal energy:

• A (primary energy process): not necessary
• B (transformation process): Marine thermal energy transfer is a heat transfer from the marine water body to a transportable material entity.
• C (primary energy): Marine thermal energy is a kind of natural ambient thermal energy that is present in marine water bodies.
• D (primary energy carrier): Still open (see below)
• E (relations): Still open (see below)

Marine current energy:

• A (primary energy process): water flow
• B (transformation process): Marine current energy transformation is an energy transformation that converts marine current energy to electrical energy.
• C (primary energy): Marine current energy is the hydro energy of moving marine water.
• D (primary energy carrier): Still open (see below)
• E (relations): Still open (see below)

Marine tidal energy:

• A (primary energy process): Tidal flow is a water flow during which movements of water masses caused by varying gravitational and rotational forces from sun and moon, combined with the rotation of the earth, cause waters to undergo periodic depth oscillations (tides). (Adapted from ENVO, see http://www.ontobee.org/ontology/ENVO?iri=http://purl.obolibrary.org/obo/ENVO_01001342. We do not care about tidal flows on other planets.)
• B (transformation process): Marine tidal energy transformation is an energy transformation that converts kinetic energy from tidal flow to electrical energy.
• C (primary energy): Marine tidal energy is the hydro energy of tidal flow.
• D (primary energy carrier): Still open (see below)
• E (relations): Still open (see below)

Marine wave energy:

• A (primary energy process): wave, see below.
• B (transformation process): Marine wave energy transformation is an energy transformation that converts marine wave energy to electrical energy.
• C (primary energy): Marine wave energy is the hydro energy of moving marine water. However, this definition is identical to the definition above for marine current energy; proposal for solution see below.
• D (primary energy carrier): Still open (see below)
• E (relations): Still open (see below)

liquid water subclasses

• water body: A water body is an accumulation of liquid water of varying size on the surface of the Earth. (Combining the ENVO definition and the Wikipedia info.)
  • ocean (alternative terms: sea, marine water body): The ocean is a water body that consists of salt water and is covering approximately 71% of Earth's surface.
  • river: A river is a water body that moves through permanent or seasonal flow process from elevated land towards lower elevations through a definite channel and empties either into a sea, lake, or another river or ends on land as bed seepage and evapotranspiration exceed water supply. (Small definition change to make it a subclass of water body instead of directly liquid water.)

water flow subclasses

• A wave is a water flow that is at the surface of a water body/marine water body/ocean and that is mainly vertically orientated.
• An ocean current is a a water flow within a water body/marine water body/ocean that is mainly horizontally orientated.
• A tidal flow is a water flow during which movements of water masses caused by varying gravitational and rotational forces from sun and moon, combined with the rotation of the earth, cause waters to undergo periodic depth oscillations (tides).

power plants and power generating units

These could (and should) be defined very generically:

• A marine tidal energy converting unit is a power generating unit that uses marine tidal energy.
• A marine tidal energy powerplant is a powerplant that has marine tidal energy converting unit as parts.
• Same for the other types of marine energy.

Still open:

• Relations between the classes. Should follow from the definitions and the general structure used for the same types of classes.
• distinction between marine current energy and marine wave energy
• primary energy carriers

[l-emele]

Results from the OEO dev 18 (flavoured with some thoughts I got when trying to summarise the results):

• Marine thermal energy:
  • A (primary energy process): not necessary
  • B (transformation process): Marine thermal energy transfer is a heat transfer from the marine water body to a transportable material entity.
  • C (primary energy): Marine thermal energy is a kind of natural ambient thermal energy that is present in marine water bodies.
  • D (primary energy carrier): Still open (see below)
  • E (relations): Still open (see below)
• Marine current energy:
  • A (primary energy process): water flow
  • B (transformation process): Marine current energy transformation is an transformation that converts marine kinetic energy to electrical energy. That is the definition we had in the pad in the end of the meeting. But as we also already have defined C, the definition of B should probably be: Marine current energy transformation is an energy transformation that converts marine current energy to electrical energy.
  • C (primary energy): Marine current energy is the kinetic energy of moving marine water.
  • D (primary energy carrier): Still open (see below)
  • E (relations): Still open (see below)
• Marine tidal energy:
  • A (primary energy process): Tidal flow is a water flow during which movements of water masses caused by varying gravitational and rotational forces from sun and moon, combined with the rotation of the earth, cause waters to undergo periodic depth oscillations (tides). (Adapted from ENVO, see http://www.ontobee.org/ontology/ENVO?iri=http://purl.obolibrary.org/obo/ENVO_01001342. We do not care about tidal flows on other planets.)
  • B (transformation process): Marine tidal energy transformation is an transformation that converts kinetic energy from tidal flow to electrical energy.
  • C (primary energy): Marine tidal energy is the kinetic energy of tidal flow.
  • D (primary energy carrier): Still open (see below)
  • E (relations): Still open (see below)
• Marine wave energy
  • A (primary energy process): wave, to be defined, see below.
  • B (transformation process): Marine wave energy transformation is an transformation that converts marine kinetic energy to electrical energy. That is the definition we had in the pad in the end of the meeting. But as we also already have defined C, the definition of B should probably be: Marine wave energy transformation is an energy transformation that converts marine wave energy to electrical energy.
  • C (primary energy): Marine wave energy is the kinetic energy of moving marine water. However, this definition is identical to the definition above for marine current energy; proposal for solution see below.
  • D (primary energy carrier): Still open (see below)
  • E (relations): Still open (see below)

Still open:

• Definition of a subclass of liquid water that covers all relevant aspects for the needs of D. Proposals for a label: water body, marine water body, ocean.
• Definition of a wave process. Maybe differentiate from other water flows by the (main) direction of the water flow (mainly horizontally in the ocean current and mainly vertically in waves).
• Relations between the classes. Should follow from the definitions and the general structure used for the same types of classes.
• We discussed using hydro energy (Hydro energy is kinetic energy of moving liquid water which can result directly from its potential energy.) as parent class for marine current energy, marine tidal energy and marine wave energy. Then we should adapt the definitions to:
  • Marine current energy is the hydro energy of moving marine water.
  • Marine tidal energy is the hydro energy of tidal flow.
  • Marine wave energy is the hydro energy of waves.
• The related power generating units and powerplants implementing the marine energy transformation process (i.e. something like a marine current powerplant). These could (and should) be defined very generically:
  • A marine tidal energy converting unit is a power generating unit that uses marine tidal energy.
  • A marine tidal energy powerplant is a powerplant that has marine tidal energy converting unit as parts.
  • Same for the other types of marine energy.

[l-emele]

What about defining the following two subclasses of water flow?

• A wave is a water flow that is at the surface of a water body/marine water body/ocean and that is mainly vertically orientated.
• An ocean current is a a water flow within a water body/marine water body/ocean that is mainly horizontally orientated.

[l-emele]

For water body, marine water body, ocean or however we will label it, here some similar definitions from ENVO:

• water body: An accumulation of water of varying size.
• marine water body: A significant accumulation of water which is part of a marine biome.
• ocean: A marine water body which is constitutes the majority of an astronomical body's hydrosphere.
• sea: A large expanse of saline water usually connected with an ocean.

None of these fits perfectly our needs but maybe we can amalgamate parts of these definitions to find a satisfying definition.

[l-emele]

Further definitions from Wikipedia (footnotes removed):

• Body of water: A body of water or waterbody (often spelled water body) is any significant accumulation of water, generally on a planet's surface. The term most often refers to oceans, seas, and lakes, but it includes smaller pools of water such as ponds, wetlands, or more rarely, puddles. A body of water does not have to be still or contained; rivers, streams, canals, and other geographical features where water moves from one place to another are also considered bodies of water.
• Ocean: The ocean (also the sea or the world ocean) is the body of salt water which covers approximately 71% of the surface of the Earth. It is also "any of the large bodies of water into which the great ocean is divided". A common definition lists five oceans, in descending order by area, the Pacific, Atlantic, Indian, Southern (Antarctic), and Arctic Oceans.
• [Sea](): The sea, connected as the world ocean or simply the ocean, is the body of salty water that covers over 70 percent of the Earth's surface. The word sea is also used to denote second-order sections of the sea, such as the Mediterranean Sea, as well as certain large, entirely landlocked, saltwater lakes, such as the Caspian Sea.

I don't think that we need the biological aspect (biome) that is part of ENVO's marine water body definition.

Connecting all these information, I propose the following structure and definitions:

• liquid water
  • water body: A water body is an accumulation of liquid water of varying size on the surface of the Earth. (Combining the ENVO definition and the Wikipedia info.)
  • ocean (alternative terms: sea, marine water body): The ocean is a water body that consists of salt water and is covering approximately 71% of Earth's surface.
  • river: A river is a water body that moves through permanent or seasonal flow process from elevated land towards lower elevations through a definite channel and empties either into a sea, lake, or another river or ends on land as bed seepage and evapotranspiration exceed water supply. (Small definition change to make it a subclass of water body instead of directly liquid water.)

[l-emele]

It would be nice if any @OpenEnergyPlatform/oeo-domain-expert-energy-modelling would give some feedback on the proposals. It is currently here only a monologue :)

[stap-m]

Thanks for the research and proposals @l-emele . I like your latest definitions of liquid water and subclasses.

[stap-m]

A wave is a water flow that is at the surface of a water body/marine water body/ocean and that is mainly vertically orientated.

If we distinguish the flow subtypes by their direction, I'd rather say a wave its vertically AND horizontally oriented, whereas tide mainly vertically oriented.

[l-emele]

In a tide, the water itself moves mainly horizontally but that is causing that the water surface level is moving vertically.

[sfluegel05]

I agree with the suggestions so far. Also, I tried to summarize the results so far in the issue header.

Based on the points which are still open, I have the following suggestions:

• use ocean current as the primary energy process (A) of marine current energy
• use water body as the primary energy carrier (D) for all four energies
• define marine current energy as hydro energy of ~moving marine water~ an ocean current.
• define marine wave energy as hydro energy of ~moving marine water~ a tidal flow.
• use the following relations:
  • [B - transformation process] has input some [C - primary energy]
  • [B - transformation process] has output some electrical energy (for all but marine thermal energy)
  • [A - primary energy process] has participant some [D - primary energy carrier]

[l-emele]

Thank your for your suggestions, they look good.

I think we are now at a stage where I can start the implementation. However, as this is a large issue, probably further open details will arise in the implementation.

[l-emele]

It probably should be:

• Marine current energy transformation is a hydroelectric energy transformation that converts marine current energy to electrical energy.
• Marine tidal energy transformation is a hydroelectric energy transformation that converts kinetic energy from tidal flow to electrical energy.
• Marine wave energy transformation is a hydroelectric energy transformation that converts marine wave energy to electrical energy.

[l-emele]

Likewise the power plants and power generating units should be subclasses of hydro power unit and hydro powerplant