ENERGY:THE FUTURE of energy is all electric, or at least it should be, according to an Irish-born Harvard professor. He argues for an electrified energy economy for the US, but the approach could work equally well in Ireland and wouldn't cost the earth – literally.

Prof Michael McElroy and colleagues at Harvard conducted a detailed study on the US’s energy future. He also has a book on energy, climate (Energy: Perspectives, Problems and Prospects) – and what to do about the whole thing – coming out this summer. He argues strongly that the US could free itself from a nasty oil habit, which costs a whopping $750 billion (€585 billion) a year for imported oil alone, win energy security and save the planet, all at the same time.

He also believes that if Ireland followed suit and took related measures it could become the “Saudi Arabia” of electricity exportation.

When taking the US into an electric future, McElroy isn’t talking about substituting oil with nuclear, but instead imagines renewable energy delivered primarily by wind but also solar. Done on a sufficiently large scale to supply the entire US electricity demand of 500 billion watts, the approach would cost a staggering $2,000 billion (€1,600 billion), but this total represents less than three years’ oil imports.

The capital expenditure could be delivered over a decade, he points out. And once installed, that investment is more or less complete. “It is a capital investment and it is there forever,” he states.

“The challenge is to build a new energy economy,” says McElroy, who is Harvard’s Gilbert Butler Professor of Environmental Science and director of the Harvard China Project. “If you think back to the end of the 19th century, with Edison, Bell, Westinghouse, the beginning of the electric age, I think we have to engineer something equivalent.”

National security represents a primary reason this approach should be pursued, says McElroy, who originally comes from Shercock, Co Cavan and has advised former US vice president and environmental campaigner Al Gore for 20 years.

Going near completely renewable using wind and solar would save billions of dollars on imported fuels. “The combination of the two means you have energy freedom,” he says. “For me the most economical way to go is wind. Wind-generated electricity is competitive with coal, oil and natural gas and the fuel is free. It is a question of capital investment and being able to connect to the grid.”

His vision for the US, developed after considerable research and analysis, is to tap into the “incredible wind supply in the prairie states, from North Dakota to Texas”. His estimates suggest capturing this energy resource could deliver 16 times the current US national electricity capacity.

One immediate problem is that the existing electrical system isn’t up to the challenge given its “antiquated and piecemeal” state, he says. “There never really was a federal-sponsored system like there was for the interstate highway system.” For this reason he argues for a new electricity supply backbone, an east-west direct current (DC) transmission line reaching from coast to coast and a north-south line running through the prairie states where the wind turbines would stand.

This idea sounds very like proposals in Barack Obama’s economic stimulus plan to build a “smart grid”. This would channel wind and solar power from remote regions to large urban centres where the greatest electricity demand is.

There are immediate advantages to choosing DC transmission, he suggests. “The energy loss over long distances with DC is considerably less that with AC ,” he says.

He also has an answer for the nimbies. “To avoid all of the inevitable problems of ‘not in my back yard’ we could run the cable along existing federally controlled highways or along the rail network. The cost of the transmission system is actually only a small part of the overall system.” It would be about €1.6 million per mile or €4.8 billion for the 3,000-mile east-west line.

The large, modern wind turbines can produce about 2.5 million watts if running at 38 per cent capacity, McElroy says. While capacity can run lower, his own study was based on locating turbines where capacity could not drop below 20 per cent.

He believes that the US, and indeed Ireland, should go all electric, with electricity-based fuel alternatives for heavy road transport that do not involve fossil fuels. “I believe we should be moving towards an electric energy system in total.”

Ireland could and should follow suit, he argues. It should evolve on an all-island basis and should also be based on good interconnectors with the wider EU grid via Britain. One such interconnector already links Scotland and Northern Ireland and, as reported in The Irish Times last week, the European Commission is providing €100 million for a new power link between Britain and the Republic.

We, too, should establish a DC transmission system connecting our wind turbines to the national grid and build wind farms to capture the plentiful wind supply.

“My naive sense is that wind resources in Ireland are enormous, particularly in the poorer parts of the country,” he says. Developing the potential could create jobs and provide extra income.

It would also give Ireland the potential to export surplus electricity. “If you have this smart interconnection, Ireland could become the Saudi Arabia of electricity supply,” McElroy says.

His study assumed that there would be no turbines in urban areas, in forests or near inland water bodies. A particularly useful location is in farming country.

“As far as the land-owner is concerned, it doesn’t effect the use of land,” he says. Tillage and livestock activity can continue with only a relatively small turbine footprint lost to production. This would be offset by a payment made for placement of the turbine.

Transport modes could all be catered for he says. Rail is easy, given the potential for electrification, but cars offer potential too. Electric vehicles run at about 90 per cent efficiency, whereas petrol engines only reach about 18 per cent, he says.

There are also options for heavy road transport. While you could use compressed natural gas from fossil sources given gas remains in plentiful supply, wind-generated electricity could be used to split water into hydrogen and oxygen.

Hydrogen can be used as a fuel, he says but “hydrogen and carbon can make methane” when hydrogen reacts with plant material, and this could also power heavy trucks.