Marine Energy: What does it mean?
Scarcely a day passes without some news item or government pronouncement on renewable energy. From the expansion of wind farms to the development of hydro-electric schemes, we are becoming acclimatised to our landscapes being shared with the infrastructure required to help Scotland reach its Climate Change targets.
Large off-shore wind farm developments are also to be rolled out shortly, which, in terms of capacity, will dwarf their on-shore counterparts, but far less is said about marine energy, despite strong Scottish Government support and a rapidly growing Scottish technical expertise.
Simply put, marine energy can be described as electricity produced as a result of wave or tidal action. The concept is not new, but the difficulty is in harnessing the power of the ocean, which can be destructive and a difficult environment to work in.
According to the Scottish Government, the seas around our shores have the potential to provide 25% of Europe’s tidal power and 10% of its wave power, so, as an added incentive, the Scottish Government has introduced the Saltire Prize - £10 million awarded to the recipient who can demonstrate that 100 gigawatt hours of electricity can be produced in a continuous two year period - the largest such prize on offer anywhere in the world.
In its favour, unlike wind, the energy from the sea can be anticipated in advance. The tide flows in a regular cycle that can be predicted almost without fail and, with the correct information on wind speed and direction, the frequency and height of waves can also be determined a few days in advance.
The trick is to harness the power and turn it into cheap, reliable energy. However, the technology to produce electricity in this way is still in its infancy, especially when compared to the proven technologies behind wind turbines and hydro-electric schemes. The cost of producing working prototypes and bringing commercially viable machines to market is high, in turn affecting the cost of producing the electricity on a commercial basis.
At present, the Renewable Energy industry is bolstered financially by what are known as Renewables Obligation Certificates (ROCs). These are green certificates issued to generators of renewable electricity generated within the United Kingdom. These are then sold to licensed electricity suppliers and, as such, have a market value. One ROC is issued for each megawatt hour (MWh) of eligible renewable output generated from most sources. However, in Scotland, marine energy tidal schemes will receive 3 ROCs per MWh of electricity generated and wave power machines will receive 5 ROCs per MWh.
A test facility “The European Marine Energy Centre (EMEC)” has been set up in Orkney, established to assist the testing of full-scale machines, developed to convert wave and tidal energy into electricity. The facility allows prototypes to transmit electricity direct to the Grid and two schemes are currently being tested, the Pelamis wave powered machine and the Oyster wave powered machine operated by Aquamarine Power.
Another contender, the LIMPET (land installed at mains powered energy transformer) based on Islay, is a shoreline energy converter which uses an oscillating water column method to generate electricity.
The ambition is to create a technical advantage here in Scotland, so that this expertise will then be sought around the world. So far, this has shown promise, with orders for Scottish based machines being taken in places such as Portugal.
With the political will in place, and an energy resource sitting on our doorstep, now might be the time to consider investing in this form of power.
For more information contact Richard Leslie