Is the tide turning?

There have been a number of milestones along the road to dealing with climate change. The most significant of these was the Kyoto Protocol, which was hammered out in 1997, but only took effect in 2005. Signatories to the Protocol are committed to the targets it contains. Although 184 countries have signed up to Kyoto, the US remains the one major standout. Looking beyond the Kyoto Protocol, leaders of the G8 group of industrial countries have agreed further climate change targets. At their recent meeting in L'Aquila, the group agreed to cut carbon emissions by 80% by 2050. But the UK Government is looking to take earlier action. Hot on the heels of the G8's announcement, it has launched the UK Low Carbon Transition Plan, which lays out how the UK will reduce emissions by 34% of their 1990 levels by 2020. Under the plan, 40% of electricity will be produced from low carbon sources, from renewables, nuclear and clean coal. Whether it's the G8 agreement or the Government's Low Carbon plan, the targets are challenging. One thing seems to be sure: technology will be the key to their achievement. Tom Delay, chief executive of the Carbon Trust, observed: "If we are to meet our 2020 renewable targets, we need a 'dash for wind' on a comparable scale to the 'dash for gas' of the 1990s. Slashing the costs of offshore wind must now be a priority for UK energy policy. With the right innovation and manufacturing strategy, the UK could see up to 70,000 jobs created and up to £8billion in revenues generated every year." One of the problems is related to where wind farms can or cannot be built. If today's regulations aren't relaxed, it's probable that the next big offshore development may be many miles out to sea; and that will increase the costs – not to mention the engineering challenges – substantially. To operate efficiently and reliably, these devices will need effective sensors, measurement technology and control systems. Wind is only one part of the renewable energy mix; marine power is another, not only offering the potential of greater energy generation, but also the prospect of huge business opportunities. Tidal power is attractive because it is regular and predictable – unlike the wind. There are a number of approaches to harnessing the power of the tides, ranging from snake like constructions to sub sea turbines. It is believed that around 100 companies are actively developing wave power technology and 80 of these are based in the UK and Ireland. The Government has recognised this potential, allocating £60m to marine renewable energy development as part of the Low Carbon package. Martin McAdam, chief executive of Aquamarine Power, said: "There is a worldwide race to develop marine renewable technology and – with the correct government support – the UK has the potential to capitalise on this and create a substantial manufacturing and export industry." Ian Bell is market development manager with National Instruments UK. A substantial part of his work is related to working with renewable energy companies. He said the renewables sector is increasingly focusing on embedded systems as an enabler. "But a lot of the things that seem easy to do are actually quite complex," he claimed. "Many systems need significant computing power to run complex algorithms, such as non linear or predictive control or neural networks. Traditionally, this would only have been available from expensive custom systems." In the past, cost wouldn't have mattered too much. "But that doesn't fit the economics of renewables," Bell continued, "where companies want to solve problems now and spend less than £5000." Ronan Doherty is chief technical officer with Aquamarine Power, which is developing the Oyster wave energy converter. "It's a novel design," he claimed, "which is different from most other devices." While most designs generally use turbine like structures for use deep water, Oyster is intended for nearshore deployment. "There's a clear benefit in our approach," Doherty continued. "Because we use hydraulic transmission of power, we don't have complicated electrical and electronic equipment offshore, which makes maintenance easier." Developing offshore power generation systems will stretch the engineering profession's ingenuity. As far as Oyster is concerned, Doherty observed: "Because of the sheer scale of developing Oyster, we have overcome significant challenges in several fields, including system control and foundation design." Controlling these devices will be a key challenge. "In deep water systems," he continued, "waves are more omnidirectional and many devices are predicated on the concept of achieving a good degree of resonance – or tuning – with them. The better the resonance, the better the power capture. "This is easier to exploit in theory than in practice, where imperfect control and power take off systems often mean that resonance is hard to achieve." The control systems used in tidal power generation systems will probably mimic those used in wind turbines – and likely face the same challenges. However, the systems differ. While wind turbines can spin to face the wind, tidal systems will need the turbine blades to be pitched to make best use of the direction in which the water flows; it's similar to reverse thrust in an airplane engine. It is believed that 40 to 60% of wind turbine faults are control related –small logic faults, for example. While that may not seem a problem, it can be serious when the control system pitches the blades at the wrong angle. Bell believes a number of challenges are apparent, including how to cut development time, how to deploy algorithms and how to get the prototype up and running quickly. "There are a lot of issues, including the use of COTS technology and high level tools. This area is proving to be good for NI and it's been interesting to see how some of our technologies are helping out." Whether you're working with wind or water, it's the cost of failure which becomes critical. "It's enormous," Bell offered. "Figures being bandied about suggest the cost of failure of a turbine could approach £1m, particularly when the turbines are getting bigger." Doherty also believes maintenance will be key. "Maintainability hasn't really been focused on yet. If you look at the sea around Scotland and Northern Ireland, for example, you can go for six weeks at a time when the wave heights are such that you can't access offshore systems. If you have a lot of devices failing, you'll need a lot of maintenance vessels. We think we have minimised this issue with nearshore installation and Oyster's simple nature." Changing consumer habits There's a lot that can be done at the consumer's end to reduce CO2 emissions and a number of approaches are being developed. One way is to include more intelligence within domestic appliances, enabling them to manage their power consumption. Amongst companies addressing this aspect is RLtec, which has developed dynamic demand technology. According to the company, this takes the form of software that can be incorporated into the control unit of electrical appliances such as fridges, electrical heaters and air conditioning units, without affecting performance. The company estimates that a fridge fitted with its technology would be able to reduce the amount of CO2 emitted by power stations by about 1tonne over its lifetime. Andrew Howe, RLtec's ceo, said that, while a fridge needs energy to operate, the energy isn't needed at a particular time. "Appliances fitted with our Dynamic Demand technology modify their power consumption automatically in response to second by second changes in the balance between supply and demand on the grid, without affecting the fridge's performance. "This means the amount of carbon emitting generating capacity used to maintain that balance can be reduced dramatically. The technology has the potential to create a 'virtual' power station and, if widely used in the UK, could eliminate the need for these carbon emitting balancing stations and save 2m tonnes of CO2 per year." In the first phase, 300 fridges fitted with RLtec's technology will be distributed to consumers to see how the technology works in everyday use. Following that, 3000 different types of fridges and freezers will be deployed so the carbon savings can be assessed and calculated against a full range of variables. Howe says: "Our analysis shows that more than two thirds of the UK's balancing capacity comes from carbon emitting sources. Dynamic Demand helps reduce that carbon intensive balancing requirement, with no loss of performance from the appliances in which it is fitted, and with no action needed on the part of the consumer." And that last comment is important. Duncan Smith, head of consumer products at Cambridge Consultants, said: "If consumers change their behaviour, it can quickly make a difference. But it's a battle if people think they've done their bit. Products have to be well thought out and it's not just a question of giving them a funny display." The company has recently constructed a demonstration kitchen at its Cambridge head office. It attempts to explore the application of more intelligence in domestic appliances and to answer such questions as 'does the fridge need to run when a kettle is being boiled?'. NI's Bell noted: "There's a lot of research about how to build a mix of generating capacity, but another part of the problem is smart metering. A mix of generating capacity handles the ups and downs of demand, but active demand management helps adjust consumption if the grid can't supply the amount of power needed." Cambridge Consultants' business development manager Chris Turner said: "Systems going live in the US allow you to pay less for electricity if you let the power provider control some of the circuits in your house. Examples include turning off the air conditioning in times of high power demand." Simon Naylor, principal electronic engineer in Cambridge Consultants' products and systems business unit, added: "As things develop, the opportunity increases to put more data in front of the consumer, so we all have a better idea of how much power we are consuming and its effect – particularly the CO2 footprint." In the end, the amount of power generated is controlled by how much we consume. The electronics industry has an opportunity to contribute to all aspects of reducing that consumption: from the ultralow power semiconductors finding their way into tomorrow's consumer electronics products to intelligent appliances and ever smarter energy consumption monitors and meters. But it needs companies to capitalise on the opportunities.