Sustainable energy is high on the European agenda. Manufacturers consistently produce appliances that consume much less energy than such products did a mere 10 years ago. Natalino Fenech looks at the use of photovoltaic panels on the island.
Daniel Talma, a Dutchman living in Gozo, has been trying to promote the use of solar panels in Malta for some time.
"I have noticed that instead of focusing on the positive, people like to criticise here. Some argue that the measures announced in the last budget to encourage the use of solar energy are not good enough. Of course it can always be better. But it is always much easier to criticise than to embrace change. It could always be better. But it could be worse too," he said.
"People have the tendency to make comparisons with Germany, where consumers who have PV systems sell electricity at a high rate and buy energy at a cheaper rate. But Germany is an exception. Most countries do not have many incentives when it comes to PV systems.
"Another thing people should not forget is that a PV system in Malta would generate about two or three times as much energy as the same system would in Germany. They don't have so much sun over there," Mr Talma said.
Mr Talma is a strong believer that it is worth investing in a PV system. "In the long run, it saves money. After the initial investment, you have hardly any costs or maintenance and you have a guaranteed lower electricity bill for the next 25 years. There is then another advantage which, admittedly, few would care about: contributing to a better environment because instead of using fossil fuels, you are using energy that is already there!
"The government has introduced net metering, which means it does not matter if you use the PV generated electricity yourself or if you sell it to the grid. In both cases, your bill will be lower. So a PV system is always saving money, whether you are using the electricity yourself or not.
"And selling to the grid has been made easy, with the meter being changed free of charge and an easy procedure," he added.
A PV system can be connected to the grid, the same power lines that bring electricity to houses, or can be installed as a stand-alone system. The latter will supply power to the building during daytime, and store the surplus generated energy in batteries. This energy is then used during the night.
In a grid-connected system, the energy produced is partly consumed by the establishment where it is installed and any surplus passes through a meter and is sold to Enemalta. Unless the site where the PV system is installed is far away from a grid, connecting to the grid is the best alternative as batteries are expensive and the amount of power they can store is limited.
Mr Talma believes that in Malta a 1kW power system should be able to generate between 1,400-1,600kWh (or units) per year. "This is 20-30 per cent of the total electricity consumption of an average family," he said.
Mr Talma can be contacted via e-mail at d.talma@mac.com.
Long-term savings
PV panels are sold in many sizes but for a normal house one would need about nine square metres of panels to produce 1kWp.
Different sizes and shapes of panels are available. As the wind can be very strong, it is important for the frame to be sturdy.
"Photowatt panels are guaranteed to work from -40 to +85°C and can handle wind speeds of up to 40m/s (metres per second). They have been tested for hailstorms and other extreme conditions and are used in cold countries as well as in Africa. So there is no reason to doubt their use in Malta," Mr Talma said.
Little maintenance is required, and this usually consists of cleaning the panels, especially following dusty rain. In Malta they will have to be cleaned every once in a while, while in countries like the Netherlands the wind and rain tend to wipe them clean.
One need not worry about risks of electrocution from PV systems. The systems shut down when there are power cuts.
"Enemalta guarantees that the voltage is between 216V and 250V and is at a frequency of 50Hz. Inverters shut off when the grid voltage is below 207V or above 253V or when the frequency is lower then 48Hz or higher then 52Hz. This means that as soon something happens with the electricity in your house, your PV system stops feeding the grid. The inverters will switch back on as soon as the voltage is back within range."
PV systems are long lasting. "The PhotoWatt panels are guaranteed to produce at least 90 per cent of their specified power for 25 years. They have an expected lifetime of over 25 years. The inverters have an expected lifetime of 20 years," Mr Talma explained.
He does not recommend going for a system which would bring one's electricity bill to zero. "You would need a big roof and an awful lot of money. A good start is a system between 1,000Wp-2,500Wp. The minimum size to be able to get the government incentive is 1,000Wp," he said.
"If one prefers to spend a large sum of money once and lower one's daily costs of living over the next 25 years then a PV system makes sense. With a PV system you have a fixed kWh price for the next 25 years. At the moment you are already paying Enemalta 6.9c per kWh (unit) for the top part of your bill, while the price of a PV kWh is about 6.4c per kWh. When the government raises the kWh price by 84 per cent you would be paying 8.3c for every kWh.
"One should keep in mind that it is expected that the price of electricity will continue to rise over the years and, when it does, you would be happy to have installed a PV system," he said.
Experiments that worked
The Mtarfa Glass factory in Ta' Qali has just started installing photovoltaic panels to produce its own electricity. Phase one of the project was completed in mid-December and by mid-January the whole system should be in place.
The system was designed by Norman Abela, an engineer who has specialised in the use of solar panels to generate electricity for the past 10 years. He has been working in the energy sector for the past 20 years, after graduating in power engineering from the University of Malta.
His thesis, entitled An Energy Study Of Malta, fitted in perfectly with the scenario of those days when power cuts were frequent. A lot of his thesis focused on predetermining what the energy consumption would be in the future to help with the planning of power stations, generation and distribution. He also conducted various energy surveys on domestic, commercial and industrial levels and outlined various ways in which energy can be used more efficiently so that electricity bills may be cut.
Mr Abela specialised in America at Solar Energy International in Colorado. He worked as a projects engineer with an American/Maltese company that manufactured PV modules and took part in various installations including a solar cabin and solar water pumping in America. He also designed and managed a gas platform in Turkey, apart from designing solar villages, telephone box lights and water pumping projects worldwide.
"The main issue with PV systems is design, not installation. You have to study the energy needs and design the system accordingly," he said.
"A number of panels on the roof of the Mtarfa Glass factory are expected to produce three kilowatt hours of energy per hour, which, in laymen's terms, means that for every hour of sunlight the system produces three units. The whole project would produce 15 units per day," he said.
Just to give a rough idea of what Mr Abela is talking about, an average of eight to 10 units of energy are consumed daily in a house.
"Industry consumes higher amounts of electricity and is usually connected to the three-phase supply. A house is connected to one phase. The Mtarfa Glass factory can boast of sporting the first three-phase photovoltaic system installed in Malta, once the system is complete," he said.
"The system came on stream on December 18, a rather cloudy day. But a computer linked to the system showed that notwithstanding the very overcast weather, the system never produced less than 150W.
"This shows that even when it is cloudy, the system still produces electricity. The clouds must be really dark for the system to produce no energy, and in Malta there are only 12 sunless days per year."
He feels there is not enough awareness of the savings that can be made by installing PV systems.
"There is so much demand worldwide that at the moment, the price of panels is rising. There is also a shortage of silicon, which is used in producing the panels. So we are embarking on this bandwagon rather late. But better late than never."
Mr Abela strongly believes that PV systems should be certified and installed by authorised technicians.
"I am not saying this because I want more work. But it is only through proper certification that one can build people's confidence. It will also eliminate from the market those who go in thinking they can make a quick buck and disappear from the market after conning a number of people.
"I feel such certification should be attached to the form requesting the grant from the government so that people can still install mediocre systems if they want to but, at least, the taxpayer will not be supporting this with the 20 per cent grant the government is giving on PV systems. Certification is the order of the day in most European countries and we should be no exception," he said.
Mr Abela can be contacted via e-mail at norman@vol.net.mt.
How PV systems work
Photovoltaic (PV) systems use panels that produce energy when they receive light. A series of panels are mounted on a frame on the rooftop and connected together with cables.
PV systems produce electricity as long as there is enough light. The more light, the more electricity they produce, hence there will be times when the system cannot produce all the electricity one needs, but there will be other times when it produces more than you need and the surplus can be sold to Enemalta. PV systems produce direct current, similar to batteries. Equipment known as an inverter converts the current to AC, which is used in homes and in industry. A meter, similar to the one installed by Enemalta, reads what is sold to the electricity company.
A PV system starts generating a few watts in the early morning, reaches peak production during the day and the power starts to wane when the sun is setting. In Malta, there is an average of five hours of sunshine per day. In February, it can go down to three hours a day while in July and August it goes up to eight or nine.
Even though the system seems to be complicated, it is very user-friendly. People who have a grid-tied system do not have to do anything except enjoy the free energy. All the switching and controlling is done by the system itself. It really is an "install and forget" system.
Solar power incentives
To encourage the use of PV panels, the government has announced that:
¤The Malta Resources Authority will not charge fees for the installation of PV systems.
¤ No fees will be levied for any permits required from the Malta Environment and Planning Authority.
¤ Enemalta will not charge any fees to change meters.
¤ A rebate of 20 per cent of the initial investment will be offered, capped at a maximum of Lm500 for the first 1kWp system.
¤ All the electricity generated and not used is automatically sold to Enemalta, and this will be subtracted from the electricity bill. A free two-way meter for registration of these units will be installed.
¤ Enemalta will introduce a refund system under which it will pay 3c a unit to a household with a PV system producing energy in excess of its needs.