The Saltire Prize should have been awarded last month, though you may not have noticed much, or indeed any, media coverage of this important milestone. Here is my attempt to remedy this oversight.

The fact that nobody has won it is a source of embarrassment to the Scottish Government and the marine energy ‘industry’ both of whom would like to forget about it. In case you have forgotten about it, here's an excerpt from a 2008 speech by Alex Salmond announcing the prize:

‘ … today I am announcing the Scottish Government’s new Saltire Prize – a call to action, and a challenge to innovate, for researchers and companies on renewable marine energy.

With a value of £10 million, or $20 million, on offer to the winners, this new Challenge prize will be one of the largest innovation prizes in the world – and almost certainly the largest ever focused exclusively on renewable energy.

…

Now, Scotland will play its full part. We have announced a call to action on marine energy, with the launch of a $20m Saltire Prize challenge that will capture the attention of some of the world’s best scientific minds – anybody across the planet who will demonstrate their devices in Scotland.

This will be one of the biggest innovation prizes in history, and the largest ever focused on renewable energy. A prize that we hope will attract the interest of scientists and companies here in America and around the world.’

To win the prize you had to deploy, in the waters around Scotland, a wave or tidal-stream energy array that produced 100GWh of output over a two-year period. As recently February 2013 the Saltire Prize website was still inviting applications and therefore assuming that there were people out there capable of winning it, but it now says:

‘… the path to commercialisation is taking longer and proving more difficult than anyone initially expected.’

This is incorrect. I predicted on the day it was launched that nobody would win it. It was obvious to anyone familiar with the history of marine energy up to that point. But to most people back in 2008, 2017 must have seemed a long long way away. So far, in fact, that it simply must be doable by then! There was, however, no basis on which to pick any particular date by which ‘it must be doable’, certainly not that it just seemed a long way off.

It's a pity that the occasion is being marked by embarrassed silence as it would be a good opportunity for a public debate about marine energy’s prospects, why it has failed to live up to its early promise and what needs to be done to make it happen.

Andrew Garrad, of Garrad-Hassan fame, hit the nail on the head in a presentation entitled ‘The lessons learned from the development of the wind energy industry that might be applied to marine industry renewables’ at a meeting entitled ‘The peaks and troughs of wave energy: the dreams and the reality’ organised by the Royal Society in 2011. Although the meeting focussed on wave energy, I think that the insights apply equally to tidal stream.

Here is what he said. In the following quotes ‘MR’ is short for Marine Renewables.

‘One characteristic of renewable energy that applies both to wave and to wind energy is that the devices are subject to large, ill-defined natural forces. At least some elements of the tidal loads are well defined and bounded. In the early days of wind energy, it was quite clear that these forces and their interaction with the turbines were not properly understood. Many surprises resulted, which, in turn, caused failures. Understanding the reasons for these accidents, and therefore preventing them, is a challenging task on its own and one that is clearly encountered near the beginning of a technology’s evolution. The author considers that MR is just entering this phase. Any real attempt at cost reduction is therefore premature.’

…

‘Few, if any, MR devices have yet been subjected to real survival conditions and yet several have failed.’

…

‘Given the relative commercial maturity of the wind industry, unrealistic expectations are being made for MR devices.’

…

‘MR, in general, and wave energy, in particular, are in the survival rather than in the efficiency stage. This statement does not imply that cost-effectiveness and efficiency are unimportant—they are vital, but secondary at present.

After prototypes, the main aim is survival alone.’

…

‘A key difference between the present MR activity and the old wind energy activities is the premature commercial environment that now seems to prevail in MR.’

Although these remarks were made in 2011 they are still true today. I’m not sure, however, that the word survival completely captures the nature of the problem. Devices don’t just have to survive, they have to produce large quantities of output with high levels of availability over long periods of time. That may be what he meant, but to me survival simply means avoiding destruction. Revenue comes from output and a device has to keep working all the time. Frequent small stoppages are just as fatal as total destruction. To the best of my knowledge no device has yet achieved anything like enough cumulative output to be considered to have been demonstrated, even if it has technically ‘survived’. The reasons for this have not been divulged but my guess is that it is because of the phenomenon described by Andrew in the first paragraph quoted above.

Ocean waves are not like radio waves or sound waves. They are random and chaotic and exert large forces. The same applies, to a lesser extent, to tidal stream, where the devices are also subject to wave action as well as to turbulence. Any conceivable pattern of forces that could act on a device will act on it. As well as being random and chaotic, wave action is cyclical and a device will typically experience between three and twelve million cycles in a year. It isn’t the one big wave that gets you, its the cumulative effect of millions of little ones.

The phrase ‘premature commercial environment’ sums up the situation perfectly. Developers have banked on future success in order to attract investment. When the expected success didn’t arrive they sought further investment to enable them to carry on. To secure this they have had to factor more unhatched chickens into their business plans and have thus found themselves on a conveyor belt that they cannot get off. This has required them to present an image to the outside world consistent with a stage of development well beyond the one they have actually achieved. Government has therefore offered the kind of support appropriate to an early commercial industry rather than a technology still in the R&D phase. Unsurprisingly this has not helped.

In his presentation Andrew Garrad made the point compellingly that, in the case of wind, the policy that succeeded was one of fostering a protected home market. But to benefit from such a market a technology has to be able to generate more than a tiny trickle of output. This is what marine energy has conspicuously failed to do. The government has been able to offer very high levels of subsidy while spending almost nothing because the machines deployed so far have generated almost nothing.

Those involved with these technologies—including developers, consultants, trade bodies and government agencies—are living in a delusional groupthink bubble that excludes inconvenient facts. The view from inside the bubble is that:

• The technologies are commercially ready but still need to reduce costs, which can be achieved via the learning curve effect stimulated by large scale deployment initially with government support.
• Investors' reluctance to invest is the fault of the investors and not of the things they are reluctant to invest in.
• Any ‘failures’ that may have occurred were due to external factors, such as the 2008 financial crisis or uncertainty caused by electricity market reform. These always strike at exactly the right moment to ruin a project just when it is on the verge of success.

If you read the trade press and attend industry conferences you will recognise this view.

The view from outside the bubble is that the technologies are still in the R&D stage and that fundamental issues are yet to be understood, never mind solved. Too many big expensive machines have been built and deployed for short periods of time while achieving very low levels of availability. The technologies are simply not ready for mass deployment.

But hang on, I hear you say, what about Meygen? Isn’t that powering ahead? Well, Meygen’s public announcements, echoed by the trade press, certainly give that impression. However, if you read these announcements carefully you will see that the facts they contain provide only limited support for the bullish impression conveyed by their language. The only press release that mentions output is dated 23 March 2017 and is entitled ‘Meygen phase 1A approaches 400MWh of generation’. It says:

‘In the first three weeks of March, average generation has been sufficient to power the equivalent of 1,250 UK homes and individually the power performance of the turbines has exceeded the contractual output guarantees, putting the project on track to achieve capacity factors significantly in excess of 40%.’

‘Homes powered’ is a particularly meaningless and annoying unit. According to RenewbleUK it equates to 3.9MWh/year which is the same as a continuous power input to a home of 445W. 1250 homes for three weeks would equate to 281MWh, which is considerably less than the headline figure of 400MWh, which itself is a low level of output for a 6MW array over a period of three weeks.

40% is a typical capacity factor for a tidal turbine. The fact that Meygen mention this number probably means that this is how much the turbines are designed to produce when operating at 100% availability. If all four turbines had been operating at that level during the first three weeks of March the output would have been 1209MWh during those three weeks. If they had been operating at that level from the beginning of March until the end of June the cumulative output would have been 7027MWh. 400MWh is small by comparison and represents a low level of availability.

The press release then says:

‘The three turbines from Andritz Hydro Hammerfest (AHH), which were installed between November 2016 and January 2017, are now scheduled to undergo onshore inspection to permit AHH to implement system enhancements derived from the lessons learned during the initial period of operations. The turbines will then be redeployed in the next available tidal window, …’

Although the next available tidal window must have been quite soon afterwards, at the time of writing there have been no subsequent announcements about redeployment or about further generation milestones. The phrase ‘implement system enhancements derived from the lessons learned’ could be interpreted as ‘fix something that broke’. Later on the press release says:

‘The AR1500 system delivered by Atlantis … is now operating autonomously at full output, exceeding all expectations.’

However, a press release dated 10 April says:

‘… the AR1500 turbine is currently being monitored to assess the effects of an unplanned grid outage. The outage was caused by a third party and was unrelated to the turbine itself. This follows a sustained period of autonomous operation of the turbine at full output, and a successful automated shut down procedure on the occurrence of the grid fault.’

‘… the AR1500 will be retrieved at the next opportunity for a full systems inspection …’

Again, at the time of writing, there have been no further announcements about redeployment or operation. It is therefore reasonable to conclude that, at the time of writing, all four turbines have been out of the water since April. This is confirmed by a paragraph in a press release dated 23 May that says:

‘The Phase 1A turbines are currently undergoing upgrades proposed by the turbine suppliers following an initial period of operation, and are scheduled for reinstallation in mid-2017 when they will undergo their final performance and reliability guarantee tests.’

A cynical person might interpret ‘upgrades’ as ‘repairs’, perhaps with modifications to (hopefully) prevent the same thing happening again. The world eagerly awaits news of the turbines’ redeployment.

Table 1 below shows data from Ofgem’s ROC and REGO register for the period October 2016 to June 2017 for output from marine energy generation stations in the UK. In this table Meygen’s generating station is called Ness of Quoys. S G E Tidal Array belongs to Nova Innovation Ltd, Tocardo EMEC Array belongs to Tocardo, and EMEC Berth 5 belongs to Scotrenewables.

Interestingly, all of the generating stations are tidal and none of them are wave.

Table 1: Data from Ofgem’s ROC and REGO register for the period 1 October 2016 to 31 June 2017

Generating station	MWh in respect of which ROCs were issued	MWh in respect of which REGOs were issued
S G E Tidal Array	11.2	36
Tocardo EMEC Array	0	2
EMEC Berth 5	67.2	83
Ness of Quoys	333.2	373

REGOs appear to be consistently higher than ROCs, so I will assume that REGOs are the most meaningful. The following table shows them broken down by month.

Table 2: MWh in respect of which REGOs were issued, by month.

Month beginning	S G E Tidal Array	Tocardo EMEC Array	EMEC Berth 5	Ness of Quoys
2016-10-01	0	0	0	0
2016-11-01	0	0	0	3
2016-12-01	0	0	0	20
2017-01-01	0	0	0	1
2017-02-01	0	0	0	128
2017-03-01	7	0	0	221
2017-04-01	5	0	74	0
2017-05-01	11	1	9	0
2017-06-01	13	1	0	0

Plotted on a graph:

These data accord with the conclusions gleaned from Meygen’s press releases. It would appear that the array was still ‘approaching’ 400MWh when it stopped and that the claim about the AR1500 turbine ‘operating autonomously at full output’ is not reflected in the data unless, perhaps, it was for a short period of time. A 1.5MW generator operating at 40% capacity factor would produce 438MWh in one month.

I do not see how the array’s performance so far could be interpreted as a ‘resounding success’ or as ‘exceeding all expectations’. Given that the array has only been ‘in the water’ since February it may be appropriate to give them the benefit of the doubt. Nevertheless, any talk of a ‘post Meygen era’ appears premature.

If those involved in the development of these technologies were to focus their efforts, to the exclusion of everything else, on solving the reliability problem, i.e. properly understanding the forces that act on devices and how to reduce their damaging effects, then success may eventually be achieved. I fear, however, that the ecosystem of actors in this sector is not appropriately structured to do this. As well as lacking the resources to engage in open ended research with an uncertain outcome, commercial device developers are also trapped in the groupthink that the technologies are commercially ready and that the only remaining challenge is cost reduction. The required research would most appropriately be done in the academic sector but so far they appear not to have focussed their efforts in this direction.

One possible route to a solution, that nobody seems to have proposed yet, is to start small and slowly increase scale as more and more experience is built up. In a famous essay published in 1926 entitled On Being the Right Size JBS Haldane said:

‘You can drop a mouse down a thousand-yard mine shaft; and, on arriving at the bottom, it gets a slight shock and walks away, provided that the ground is fairly soft. A rat is killed, a man is broken, a horse splashes. ’

The marine environment is like that mine shaft and the devices that have been built so far are like that horse (well, maybe the rat). What we need is the mouse.

If I were in the wave or tidal stream energy business I would start with a very small device, whose longest dimension was less than a metre and which was capable of generating less than a kilowatt. I would deploy it in a location where the resource was of an appropriate scale, such as a sheltered estuary where the waves are fairly small or where there are currents close to shore. The device would have to export power to shore though not necessarily into the grid. I would leave it out there until it stopped working. Then I would investigate the root cause of the failure and redesign it to eliminate the problem. I would keep doing this until the device was capable of working for at least three years with only scheduled maintenance, preferably with a frequency of less than once per year. Then I would design a slightly larger device and repeat the process. Eventually I would end up with a large device that you could put out there and then just sit back and collect the megawatt hours. This process could take 20 years or longer, but the current approach has been tried for that long already and hasn’t worked.

I sometimes think that the current crop of device developers actually are adopting this approach, but with full scale devices, each costing around £5M, instead of small ones. As well as being a lot more expensive, doing it that way takes longer because of the time and effort required to raise the huge quantities of money needed for each iteration of the process, and cannot be sustained for long because funders will get fed up with throwing good money after bad.

One way of implementing my approach cost effectively would be to find niche markets for small wave and tidal devices. For example, it is easy to imagine that the owners of luxury yachts may like to have weeny pelamises (or should that be pelami?) that they can throw overboard when they need a few kW to boil a kettle. It’s no surprise that the only commercially successful wave energy device ever was Commander Yasuda’s wave-powered navigation buoy. The wisdom of this approach is demonstrated by the fact that most successful renewable energy technologies started that way. PV, for example, was for decades only ever deployed in the form of very small units for generating power in remote locations where it was otherwise unavailable. Wind also started small, as Andrew Garrad explained in his paper referred to above.

I suggest, therefore, that the Scottish Government should offer a new, smaller, Saltire Prize, for ideas for niche markets for very small wave and tidal devices.

Post script 08 August

I have just discovered two news reports, one in reNews and the other on Proactive Investors, both dated 10 July, saying that two of the four Meygen Phase 1A turbines have been redeployed and that the remaining two are expected to go back in the water in September. I didn’t spot this earlier because, for some reason, there was no press release in the news section of Atlantis’ own website. I’ll have another look at the ROC and REGO data sometime next year to see how they’ve been getting on.

Post script 09 August

Earlier this morning a press release has appeared on Atlantis’ web site saying that the Meygen Phase 1A has just passed the 1GW milestone. Data for July have now appeared in Ofgem’s REGO register which reports that in that month the Ness of Quoys generating station was awarded REGOs corresponding to 554MWh. Assuming the two turbines commenced operating on 10 July then this corresponds to a time period of 21 days or 504 hours. At 40% capacity factor, a 3MW array should generate 604MWh, so within experimental error it looks like they operated at 100% availability during that time. I wonder how long they will be able to keep this up?

© Copyright 2017 Howard J. Rudd all rights reserved.