Last month, the Malta Resources Authority held a series of information sessions to spread public awareness on making the most efficient use of energy. EU target deadlines for renewables are only a few years down the line, so as a country we need to get a move on.
In the light of grant schemes to promote renewable energy and saving energy, MRA chief executive officer Anthony Rizzo noted that taking out a grant to install photovoltaic panels on one’s house did not make much sense unless the occupants also tried to improve energy efficiency inside their homes.
Engaging in an energy audit, now a cost-free measure as encouraged by the new Budget, should become a basic exercise for all households.
Policy and design guidelines in place since 2007 have been calling for building design to favour energy efficiency through use of insulation, location of windows, shading and other means of natural cooling and heating. It is the role of the Malta Environment and Planning Authority to promote this concept, especially in large projects. According to development services manager Victor Sladden, Mepa’s role in this area is set to increase as part of an update to the current guidelines.
Ideally, a renewable energy installation should be designed as an integral part of the building, not as an afterthought. In a wider context, the surroundings, orientation and materials used should also enter the picture.
Engaging in an energy audit, now a cost-free measure as encouraged by the new Budget, should become a basic exercise for all households
The planning approach to placing solar water heaters on rooftops is that their benefits outweigh any visual impact, although some refinements may be in order.
Charles Yousif, overseer of the first solar system to be connected to the grid in Malta, spoke out on different types of renewable energy systems. Solar water heaters give an excellent return for money invested, but no one solution should be done in isolation, he said, adding that lack of energy-efficient buildings can cancel out any gains from solar energy. “Do everything you can to meet the target,” he concluded, in a reference to looming EU deadlines.
Alluding to the now outdated guidelines, he insisted that the concept of heat pumps for heating water must make an appearance in any update of the Mepa document, since they involved a saving of 70 per cent over water heaters.
“Why do we think the geysers are the best solution?” mused Prof. Yousif, “We must learn to do away with them altogether one day.”
The solar engineer also warned about cramming air conditioners into shafts in apartment blocks. A local study has measured the ‘island effect’ when hot air pours into a shaft where several air conditioners are installed, only for the heat to be reabsorbed back through the building’s walls again.
Underlying garages can rob heat from a house in winter. In this case, it is best to insulate the floor. Absurdly, while 20 to 24 degrees Celsius is an optimum temperature for human comfort, some people set their air conditioners so low on summer nights that the use of a blanket is necessary. This simply does not make good energy sense and runs up steep electricity bills too.
On the other hand, spending the winter months in sub-standard temperatures below 18˚C can be damaging to health, causing humidity and possible arthritis.
Alex Torpiano, head of the University’s Department of Structural Engineering, gave a number of helpful tips for anyone planning to install photovoltaic panels on their rooftops.
A major consideration is avoiding damage to the panels caused by high winds. To secure a panel robustly to a concrete roof may entail making a hole to find the hard concrete level, and then carefully re-sealing any puncture points in the waterproof membrane.
High-quality of workmanship is important if trouble is to be avoided here, and the job should only be entrusted to qualified people. Using adequate ballast is a fair alternative to puncturing a waterproof roof.
Fitting wire stays diagonally can help stabilise the PV installation against any rough weather. It is best to make sure that everything nearby in the immediate surroundings is secure so that nothing can fly onto the panels and cause irreparable breakages.
Beyond the risk of having panel structures uprooted, it is crucial to avoid damage to the panels themselves through excessive flexing during high winds. Much research is presently focusing on flexible PV elements, and some are already on the market. Although these may be costlier they could be ideal for historic centres such as Mdina where they can be laid directly on the roof surface, even withstanding soft treading without sacrificing roof space.
Planning ahead for large-scale installations of PV may include resorting to modelling tools for predicting how the panels will respond to wind flow. Adjustment of the tilt angle and adding wind deflectors to the underside of the panels can help. Walling the roof edge can cause friction but a wind curtain can be created with perforated screens which provide a barrier.
Dwelling on eligibility for the schemes and feed-in tariffs, George Cassar noted that the photovoltaic panels scheme was residential (for residents, not landlords) and the system had to be connected to the grid. Full or partial export to the grid are two interchangeable options.
The same household is not allowed to make use of more than one grant for renewable energy technologies. Applications must be sent in by the applicant, not the retailer, and payment of the remaining 50 per cent must be through traceable means, excluding cash.
Renewable energy installations can improve the value of a building, and insurance agencies may offer a green discount.
Rizzo also gave an introduction to a recently launched scheme for rehabilitation of wells, open for applications until the end of the year. The incentive is aimed at halving the cost of repairing a well.
Any plumbing installed to enable the use of stored water in households is eligible to be funded for 50 per cent of the cost. Making this source of water more available to households for certain purposes is an indirect energy-saving measure, since tap water comes with its own energy costs.
Well water is not recommended for drinking, cooking or showering/bathing, even if boiled. But it is acceptable for washing of clothes and floors, and to water the garden.
When it comes to plumbing for second-class water uses (also funded by the scheme) mains water should be kept completely separate from well water at all stages. The grant scheme gives a one-year leeway for works to be done to allow for the dry season to come around.
The Local Councils Association will be hosting local and international speakers at a conference in Sliema on November 28 and 29 on improving public access to energy initiatives.
Free software may be downloaded from www.sunearthtools.com. A utility tool to check performance of grid-connected PV systems in Europe, developed by the Joint Research Centre, is found on the MRA website http://mra.org.mt/support-schemes/ technical-schemes .