Some more energy realities

Marco Cremona made some telling points in his piece 'We need energy realities' (The Sunday Times, July 20).

It is certainly the case that on curbing GHG emissions we are in a quandary, principally because we have done nothing on the two major emission fronts: electricity generation and transport.

On the generation side, we have had to cut out the CO2 contingency buffer to conform to EU limits for 2008 to 2012.

Despite the precarious condition of Enemalta - we have already had a number of power cuts this summer - the government has not presented the fabled deep-water wind farm as a solution to these imminent difficulties.

There is the further point that the present isolated grid cannot support such a large wind farm, given the intrinsic variability of wind.

Even with a farm half that size, the Sicily cable would need to be in place to provide a buffer - absorbing surplus energy on occasion, and supplying the deficit on others - and that is quite apart from technological risks. However, one risk that does not exist is the one connected with Cremona's statement that "this country has no wind or sea current data on which to make accurate predictions".

We do have data for a number of on-shore sites from which the energy yield of a specified wind farm can be worked out.

The quickest way to generate a significant RE contribution is by one or two on-shore wind farms using well-proven technology and turbines of a scale suitable to this country - which is what the Sicilians are doing, from Trapani all the way to Catania.

Cremona is right to mention solar water heaters, but these are getting a bad press from people who hold to the superficial position that the SWH provides you with most hot water when you least need it, in summer. The answer to that is that the correct solar water heating installation is one that supplies all the hot water needs of a home.

Cremona does not mention PV. While much more expensive than solar water heating, PV is gathering momentum with the Malta Environment and Planning Authority, ministries, schools, banks, and a few industrial establishments with installations. Domestic PV is still very restricted; and with solar water heating, it is now running the gauntlet of third storeys and penthouse blocking off the light.

The other energy reality that Cremona, most uncharacteristically, passed over is that relating to water supply.

We are already running a reverse osmosis plant on Gozo to polish ground water. Its energy consumption is a secret; some 50 per cent of input water is rejected and dumped in the sea.

In case of shortage, the balance is made up by the Cirkewwa plant, via the undersea pipeline - placing more demand on the power stations, of course.

The second class water from the sewage treatment plant at Ras il-Ħobz is also going into the sea. So irrigation uses ground water; but irony of ironies, the reason given for installing the polisher was that farmers were finding borehole water too saline to use for irrigation.

Their part in rendering it so by ruthless over-pumping is not mentioned.

Coming to this side of the Fliegu, we have no plans to use second class water from the two upcoming sewage treatment plants.

But we do have plans to demolish the six million-cubic metre source under Miziep by passing the Xemxija section of the trans-European Highway under the pumping station at l-Imbordin.