Offshore wind could power the world

A sailing boat passes the Kentish Flats offshore windfarm. Photograph: Gareth Fuller/PA
Source: The Guardian

There are several carbon-free ways to generate electricity: hydro, onshore wind, offshore wind, solar PV (with either fixed or variable tilt), concentrated solar power (CSP), green methane and hydrogen (i.e., methane and hydrogen manufactured using wind and solar), biomass, nuclear fission (too expensive, too polluting) and nuclear fusion (not yet functional, except possibly for this).    The grid of the future will likely use all these methods, except for nuclear fission, because they complement each other.  The wind blows when the sub doesn't shine, offshore wind is less variable and stronger than onshore, CSP can deliver power 24/7, seasonal storage using green methane/hydrogen will cover week-long periods when wind and solar are low. 

From The Guardian:

Erecting wind turbines on the world’s best offshore sites could provide more than enough clean energy to meet global electricity demand, according to a report.

A detailed study of the world’s coastlines has found that offshore windfarms alone could provide more electricity than the world needs – even if they are only built in windy regions in shallow waters near the shore.

Analysis by the International Energy Agency (IEA) revealed that if windfarms were built across all useable sites which are no further than 60km (37 miles) off the coast, and where coastal waters are no deeper than 60 metres, they could generate 36,000 terawatt hours of renewable electricity a year. This would easily meeting the current global demand for electricity of 23,000 terawatt hours.

“Offshore wind currently provides just 0.3% of global power generation, but its potential is vast,” the IEA’s executive director, Fatih Birol, said.

The study predicts offshore wind generation will grow 15-fold to emerge as a $1tn (£780bn) industry in the next 20 years and will prove to be the next great energy revolution.

The IEA said earlier this week that global supplies of renewable electricity were growing faster than expected and could expand by 50% in the next five years, driven by a resurgence in solar energy. Offshore wind power would drive the world’s growth in clean power due to plummeting costs and new technological breakthroughs, including turbines close to the height of the Eiffel Tower and floating installations that can harness wind speeds further from the coast.

The next generation of floating turbines capable of operating further from the shore could generate enough energy to meet the world’s total electricity demand 11 times over in 2040, according to IEA estimates.

The report predicts that the EU’s offshore wind capacity will grow from almost 20 gigawatts today to nearly 130 gigawatts by 2040, and could reach 180 gigawatts with stronger climate commitments.

In China, the growth of offshore wind generation is likely to be even more rapid, the IEA said. Its offshore wind capacity is forecast to grow from 4 gigawatts to 110 gigawatts by 2040 or 170 gigawatts if it adopts tougher climate targets.

Birol said offshore wind would not only contribute to generating clean electricity, but could also offer a major opportunity in the production of hydrogen, which can be used instead of fossil fuel gas for heating and in heavy industry.

That this report comes from the IEA is telling.  It has in the past been far too conservative about the cost declines in renewables and about the rise in the penetration of renewables in the grid.  Good to see an analysis which is less favourable to fossil fuels.

There are no technological or financial impediments to de-carbonising our entire electricity grid.  The constraints now are political.