In today's world, the energy consumption is primarily derived from fossil fuels which include oil, coal and natural gas. However, as time goes by, dependence on fossil fuel as a primary source of energy continues to grow.
Since the present rate of extraction of fossil fuel grows every year the obvious question of how much natural reserves would last often crops up.
To answer this dilemma several conflicting estimates and forecasts have been put forward, but to date there is no specific answer to this question. Nevertheless, what is known for sure is that the amount of fossil fuels is indeed limited, and there could be a time where these natural resources would be exhausted.
The price of fossil fuels is determined internationally according to market forces, that is on supply and demand. The cartel phenomenon dominates the supply side; as is the case with OPEC for the oil industry.
During the last decades demand for oil has been continuously increasing, and as a result the price of fuels has in general shown an upward trend.
Technically, the process to release the energy contained in fossil fuel is called combustion, which involves the burn down of the fuel, where heat is generated and then transformed into some other kind of energy such as electricity.
The fossil fuel resource does not only contain the energy required, but also other chemical elements. Unfortunately, besides the release of energy, during the combustion process several by-products are created, including toxic gases.
Such sulphur and carbon-based gases, which harm the environment, are also a threat to public health. It is these gases which produce the green- house effect, and acid rain, for example, and which the Kyoto protocol aims to reduce.
In Malta gas emissions from the Marsa and Delimara power stations are classical examples of toxic substances which are by-products of combustion, as are the toxic gases emitted from cars running on either diesel or petrol engines.
There is no doubt that the toxic gas emissions from the Marsa power station are much higher than those from Delimara.
To this end, the engineering and scientific community around the world have intensified research on new systems that generate energy from other sources which are not dependent on fossil fuel, and would in turn be compatible with the environment at reasonably competitive prices.
There are many types of renewable energy resources which are becoming popular around the globe. Solar, wind, and hydropower are a few of them.
Solar energy can be collected in two forms. The first type, which is the best known, is the thermal type, whereby heat energy from the sun is collected via panels and transferred to the water.
Such systems are commonly used in countries where the climate is warm, including many Mediterranean countries, and Australia. The system consists of panels installed on the roof or places which enjoy a considerable amount of sun, by which the heat energy is transferred from the sun to the water.
This provides the user with warm water, without the full or partial need to use any electrical-assisted or gas-fired boiler. The European Solar Industries Federation (ESIF) quotes the sales of solar collectors to be about a million square metres per year with major markets in Germany, Austria and Greece.
It predicts that sales will grow by 23 per cent per year till 2005. ESIF specifies that the installed collector area in the EU amounts to over 7 million square metres.
Annually it saves 1.4 million tonnes of carbon dioxide emissions, the equivalent of 450,000 tonnes of oil, while this industry created around 10,000 new jobs.
The heat from solar energy could also be used for heating swimming pools, industrial heating and air-conditioning systems, for instance. In Malta, although there are some thermal-solar collectors installed, for some reason, their diffusion is not as high as in the other Mediterranean countries, including Cyprus and Israel.
Another source of energy which can be derived from the sun to generate electricity is the use of light energy. Solar panels, which technically are called photovoltaic (PV) panels and which are similar to the ones used in outer space activity, are mounted where they can be exposed to the sunlight from which they can absorb light and generate electrical energy.
In practice such panels can generate on average 100 Watts (peak power) per square metre. Several panels which when connected together form an array can generate a substantial amount of electricity.
In some cases electrical energy from such photovoltaic arrays can be sold to the national electricity grid, if not consumed at the instant it is being produced, or stored in some form for future use.
Such applications are ideal for remote areas, where the cost of cabling makes the use of photovoltaic applications feasible and viable. Photovoltaic installations are becoming more popular on rooftops and they can also be incorporated on façades of buildings.
Other areas where such applications have been tested are in street lighting and cars, among others. Photovoltaic panels were installed on a car by the author in a project in the early 1990s.
The present high cost associated with the production of photovoltaic panels, is one of the major problems which this industry aims to tackle.
Moreover, the efficiency of these panels is about 10 per cent, and it therefore requires a large area in order to generate substantial electrical energy.
In future it is estimated that as the efficiency of the panels increases and the cost of production decreases the feasibility and viability of photovoltaic applications would also be substantially increased.
The road map published by the National Centre for Photovoltaics of the United States specifies that it aims to penetrate the domestic market by 10 per centre of the US peak electricity generation capacity by 2030.
This is equivalent to some 180 million barrels of oil in that year. The European Photovoltaic Industries Association (EPIA) aims to have a cumulative installation of 2000 MW peak of installed photovoltaic power in Europe by 2010.
Out of these 900 MW are on roofs, 400 MW are to be installed on façades, 400 MW are to be connected to the grid, 100 MW in isolated homes and 200 MW in other applications.
EPIA also forecasts that by 2010, more than 150,000 people would be employed in the photovoltaic industry, out of whom 32,000 would be in Europe.
Wind energy
Another popular, and also diffused, form of renewable energy resource is wind energy. In the last decade wind energy become one of the popular alternatives to fossil fuel for the generation of electricity, and is used in several countries.
A wind turbine is the name used for equipment needed to collect the wind and transform it to electricity. Normally, wind turbines are not installed on their own, but it is more practical to instal them in a group which is termed a "wind farm".
Such wind farms can be found either onshore, or when land space is limited, offshore.
According to the European Wind Energy Association (EWEA), there has been an increase of about 40 per cent per year in the past six years in the use of wind energy.
Today wind energy in Europe provides enough electricity for five million domestic users. About 60,000 MW of wind energy capacity are set to be installed in Europe by 2010 and this would serve around 75 million people.
Denmark is one of the leading users of wind energy to supply its inhabitants. The Danish Wind Industry Association (DWIA) reports that in Denmark some 2000 MW of electrical power is generated by around 6,000 wind turbines, 80 per cent of which are privately owned.
The Danish Energy Authority claims that in 2000, 4.42 TWhr were generated from wind energy. This is an increase of around 50 per cent on 1999.
The UK is another country which is picking up on the generation of electricity derived from wind energy.
England is said to be in a good position where wind is not scarce. At the moment there are plans to build a 38-turbine offshore wind farm with a generating capacity of 76 MW at Middle Scroby Sands, around three km from Great Yarmouth, Norfolk. Other onshore installations are also in the pipeline.
Considering that Malta is an island and the wind statistics give an indication that there is no scarcity of wind, offshore wind farms would be an idea that needs to be seriously considered.
We could for instance aim to have a certain percentage - say a conservative figure of 10 per cent - of our electricity supply derived from this renewable resource.
Having some component of the electricity supply dependent on wind, would mean a reduction of fossil fuel burned in our thermal power plants, and thus less toxic gases emitted in the environment.
Hydropower
Another form of renewable energy resource which is quite popular is hydropower. This makes use of the potential energy contained in the flow of water in rivers in order to drive hydro-turbines that in turn generate electrical energy.
This form of resource is very popular in Norway where the country has an abundance of rivers. It has more than 850 hydropower plants.
According to the US Energy Information Administration (EIA), Norway has no petroleum-fuel power plants, and its domestic electricity is 99 per cent dependent upon hydro-power, while the rest is imported.
Unfortunately, in Malta this form of energy is not available, and hence could never be exploited.
There are other forms of renewable energy which are currently being researched internationally. These include tidal energy. However, at the moment there is not yet a commercially energy-producing project for tidal energy.
One inherited technical problem in the use of renewable energy sources is that the electricity generated depends on the amount of the resource available, and not upon the demand, as opposed to the electricity derived from fossil fuel.
Several methods are being developed in order to solve this problem. Arrangements could be made so that electricity that is generated from renewable energy sources could be sold to the grid when not used by the consumers.
In some countries, bidirectional meters which register also the amount of electricity which is sold to the grid (this is then deducted from the consumer's bill) are used for small photovoltaic arrays installed on homes.
For high volume power plants that generate electricity from renewable energy source, the energy could be sold to the grid at a market traded price.
At the moment the several scientific and engineering institutions are focused upon the development of several storage methods. This so that when the energy generated from renewable energy resources exceeds that consumed, the energy could be stored and used when the situation becomes the opposite.
One method which is highly popular is the generation of hydrogen from the electrical energy which is easily and practically stored. Then by making use of a fuel cell, hydrogen is combined with oxygen (which is readily available in the air) in order to produce electricity and water.
Other storage methods make use of large mechanical flywheels, and in the case of hydropower water is pumped at higher levels when consumption is low and then used when consumption increases.
The technology of using renewable energy resources is already available, and although it is being improved, further developed and enhanced, some countries are already reaping its benefits.
Malta has not yet exploited these energy resources, and our main consumption of energy is mostly dependent upon fossil fuel. There could be several factors which have hindered the use of renewable energies in Malta.
However, it is believed that the principal factor is finance. Since energy constitutes one of the basic elements for a decent living, the present local electricity tariffs are highly subsidised by the government, so that the price of such resource would be affordable by everyone.
In the renewable energy generation of electricity only the resource is available without any cost. Capital investment is needed in order to commence the generation of electricity, and then recurrent expenditure is also incurred to keep the system running and the service on offer.
The present subsidised electricity tariffs which are sold to the consumer make investment in renewable energy resources unattractive.
It is therefore imperative for the government or the energy regulator to intervene in order to solve this abnormality. Several options are recommended, including the extension of the government subsidy to include energy generated from renewable sources, so that both methods can compete on a level playing field.
Another option is to charge the consumer the market price for electricity without any subsidy but then offer financial assistance to those who fall below the poverty line.
Also several tax incentives should be offered to commercial and industrial consumers or private energy enterprises that opt to invest in the generation of energy from renewable sources.
Such incentives could be similar to the ones that some businesses are eligible for by virtue of the Business Promotion Act (Chapter 325).
In general the trend of the energy supply of the 21st century is to incorporate more the use of renewable energy resources, and reduce dependence on fossil fuels.
Reduction of the toxic gases which harm the environment and make the price of energy more affordable are also part of international goals. Nevertheless, besides make energy more affordable, renewable energy offers the advantages of being accessible, sustainable, and compatible with the environment.
It is for these reasons that renewable energy is termed as "the energy of the future", and Malta should do its utmost to exploit such a natural resource.
Dr Richard Blundell, B.Eng. (Hons.), Ph.D., can be reached by e-mail at blundell@iee.org