Engineers for alternative energy
As islanders we enjoy generous amounts of sunshine, a good amount of wind and ample wave power across the span of any one year.
It is perhaps for this reason that the Chamber of Engineers focused its 20th annual conference last month on alternative energy and how the local renewable energy scene is evolving.
In his opening address, the Resources Minister George Pullicino noted that projects on a scale large enough to meet a significant proportion of Malta’s renewable energy target were not easy to come by.
Land space available per capita for developing our sources of renewable energy is restricted.
Out at sea the challenges of installing a deep water wind farm remain an obstacle, with select spots in shallow waters the only feasible option.
As for meeting emissions targets, smart meters, which are to gradually replace the present system over the next two and a half years, would allow consumers to be more pro-active toward energy saving with more informative billing.
Currently 67,000 square metres of photovoltaic (PV) panels are being installed on rooftops of public buildings while the ministry is looking at how to promote a further 70,000 square metres of PVs on other buildings.
Certified installers of solar systems who have successfully completed new courses starting this month at the University and Malta College for Arts, Science and Technology will be listed on the website of the Malta Resources Authority (MRA). By the end of next year all solar system installers are to be qualified in line with the EU directive.
The chamber is proposing to the MRA and government to have qualified technicians and warranted engineers for installation and certification of PV systems.
Chamber president Saviour Baldacchino said that while certain initiatives were appreciated, the authority needed to be more open during its consultation processes and ensure that PV systems bear certification of a warranted engineer in the interests of public safety and consumer protection.
In a keynote address, Manfred Weissenbacher from the University’s Institute for Sustainable Energy observed that renewable energy could be driven by both climate change and energy security issues. Ultimately it presented an opportunity to create a better, cleaner world.
Weissenbacher pointed out that switching to a diet containing less red meat could also help reduce greenhouse gas emissions. A UN report identified the livestock industry as having an even greater impact on global warming than the entire transport sector. (This has been hotly contested by the meat industry for not factoring in deforestation for transportation infrastructures).
“Any diversification of the energy mix will increase energy security. The advantage of renewable energy is that it is locally available. Renewable energy uses a fuel that is practically free but requires a lot of investment upfront. Due to intermittency, a good portfolio of different renewable energies which compliment each other is needed while better solutions for energy storage would be helpful,” added Weissenbacher.
Currently involved in researching renewable energy sources that could be applicable to Malta, Luciano Mule Stagno from the University’s Institute for Sustainable Energy noted that recycling issues with thin film solar panels and availability of materials was likely to carry silica forward as a clean component of PV cells for at least the next 10 years.
Wave energy is generated more by storm and wind-driven waves than swell in the closed Mediterranean Sea. Cedric Caruana Mifsud from the University’s Faculty of Engineering described how this technology was progressing.
A hydraulic system is currently the more mature technology. Research is ongoing on a direct electrical system that could operate in a wider range of sea conditions.
Wave energy parks would deploy devices to smoothen output and load energy could be stored on each device. More measurements from particular sites are needed since energy capture is more complex for the high-frequency, wind-driven waves seen around Malta’s shores.
The question of whether or not the wave resource is sufficient to make commercial harnessing economically viable cannot be answered without more research.
“You cannot just get a device that was operating somewhere else and put it in the water… it has to be tuned to the conditions of Malta,” said Caruana Mifsud, adding that significant input from diverse fields of engineering would be needed to develop wave power.
Development of a wave energy converter in Malta under the Malta Council for Science and Technology research and innovation programme includes design and testing of three buoys. The Blue Ocean Energy project financed by the council project is still at an early stage.
The long-awaited decision on setting up a wind farm still hovers between waiting a number of years to get a better idea of long-term conditions on site and the ever-pressing need to set up and start working.
Wind speeds vary over the course of a day, season, and even from one year to the next, making it a challenge to get a comprehensive estimate of wind conditions at any particular location.
The quest to capture the energy of a stronger wind force by going higher is pushing engineers to build structures upward, which in turn pushes up costs.
At the lower end of the scale, analysis of how wind behaves below the 10 metre mark in central and southeast Malta has been the focus of a visiting undergraduate student’s project.
Although results of the low-level wind monitoring project are preliminary, Robert Farrugia of the Institute for Sustainable Energy considers them to be “enlightening”, as they “show where perhaps we should go in the near future”.
Monitoring in a highly complex urban environment, different from wind conditions over desert terrains or at sea, is essential to quantify the wind resource for micro-applications on a small scale.
Senior consultant with Mediterranean Technical Services, Godfrey Muscat, spoke on the importance of design in hotel air conditioning systems. An electric motor running at no load is already running at 30 per cent efficiency. A multiple system is always an advantage in case of part failure.
“If your AC system cannot cater for part load you will be paying for peak load throughout,” cautioned Muscat.
An overview of market developments in the field of PVs was given by Karl Azzopardi of Solar Solutions Ltd. While grant schemes have been a good start it was difficult to understand why payment of a feed-in tariff for electricity exported to the grid was limited. Currently it is capped at 4,800 kilowatt hours for domestic premises and 160,000 kWh for commercial premises.
Retired aircraft engineer Alessandro Urso (now based in Gozo) firmly believes that energy is a matter that should be decided by the people at local council level. Along with a local manufacturing firm which has diversified into the renewable energy sector, he is designing to cost for a low noise vertical axis wind turbine. This type of turbine can supply power for households, farms and industrial uses.
The conference heard how Enemalta Corporation’s project manager for the controversial new plant at Delimara power station was still waiting for an integrated pollution prevention and control permit from the Malta Environment and Planning Authority for heavy fuel oil sludge in connection with the centrifugal system and use in boilers.