Offshore-wind-energy

Long-lasting coatings for offshore renewable energy

EU researchers have developed an innovative and environmentally friendly new aluminium-based coating to provide protection for offshore energy installations.

The Advanced Coatings for Offshore Renewable Energy (ACORN) project has developed a new protective coating that will extend the lifetime of marine structures to 20 or more years and avoid the need for supplementary cathodic protection.

The result will be an entirely new, non-paint solution for the protection of offshore renewable energy steel structures including docks, buoys, and oil and gas rigs. Once successful, the coating will boost the competitiveness of the industry and help trigger a widespread roll-out of the different offshore technologies.

Corrosion, fouling and cavitation represent a huge challenge for the industry, especially since offshore structures cannot be dry-docked to fix these problems.

Use of a pure aluminium coating

The project involved the creation of a highly differentiated and patentable technical solution that could even be extended in the longer term. It uses thermally sprayed aluminium (TSA) – a substance with proven long-term corrosion resistance – to provide a matrix coating with a lifespan of 20 + years.

This porous mix is then dotted with environmentally-friendly active antifouling substances in very tiny concentrations (< 1 %) which will be gradually exposed at the active surface of the coating as the TSA corrodes away at a rate of 10µm per year.

Project scientists chose a 99.5 % pure aluminium coating applied with the twin arc spraying method. The eco-friendly anti-fouling substances were then chosen for their performance, commercial availability and regulatory approval for use in EU waters.

Scientists also evaluated the inert antifoul carriers for stability in seawater, hydrophobicity and for low processing temperatures to protect the anti-fouling agents. Barnacle resistance tests were then undertaken in marine trials off the coast of Sweden.

Coatings for tidal power to boost lifespan

ACORN is also developing a corrosion and cavitation-resistant coating with a 10 + year design life for tidal energy generators which operate in high-velocity environments.

Three coatings were selected: a tungsten carbide containing alloy, an aluminium oxide and an iron-based alloy. They were chosen for their behaviour under cavitation conditions, compatibility with the substrate material, corrosion performance, a lack of heavy metal content, environmental safety and finally, cost and manufacturing considerations. The three substances were coated onto initial test coupons and assessed for resistance to both cavitation and seawater corrosion.

Computer simulations supported the studies on hydrofoils and model turbine blades in a cavitation tunnel to fully assess each coating’s performance under expected service conditions.

Now that the project is working on the commercialisation of the new coating, it is hoped that this will make a major contribution to providing environmentally safe solutions as global energy demands and a shift towards renewable energies will likely see the construction of more offshore energy installations over the next decades.

(Source: www.phys.org)

solar balloon

High-Soaring Balloons Could Be The Future Of Solar Energy

When it comes to solar energy, we’ve long known that solar panels must be placed in areas with as much access to sunlight as possible for optimal power output. But even then, clouds or bad weather can interrupt energy production.

Now, it turns out, the scientists at the Japanese-French Laboratory for Next Generation Photovoltaic Cells in Tokyo are developing a way to solve this problem: by placing solar panels above the clouds.

“You get much more light up there,” Jean-Francois Guillemoles, co-director of the NextPV lab, told The Huffington Post. “There is a potential that generated electricity from this technology, when mature, could be made at costs much lower than that of coal.”

The researchers are investigating how to use mostly lightweight polymers to make giant solar panel balloons equipped with generators. The balloons would be tethered to the ground, and their cables would transmit the electric power down to Earth. The diagram below explains the idea.

The researchers plan to float the generators just above the clouds, about 6 kilometers (roughly 3.7 miles) high and below airplane routes, Guillemoles said. But a possible long-term option would be for the balloons themselves to float even higher, at around 20 kilometers (about 12.4 miles) high.

Sunlight is approximately five times more abundant above the clouds than it is on the ground.

“It has the potential to make solar energy more sustainable and faster to deploy at large scale,” Guillemoles said.

The idea of locating a solar farm high in the sky isn’t new — proposals to use solar power from Earth-orbiting satellites date back to the 1970s, for instance — but only preliminary studies have been presented so far, according to Guillemoles. NextPV lab is looking into launching a prototype as a next step.

“As far as I know, there is no real demonstration of any sort, and that is what is needed at this stage,” he said. “We should explore paths that have potential for solving our more pressing issues: sustainable development for all, security and safety of energy supply, and large-scale deployment.”

When it comes to the future of energy, what other ideas are out there? Watch the “Talk Nerdy To Me” episode below for four promising sources of energy that just may power our future.

(Source: Huffington Post)

Renewable energy supply to double in major economies by 2030

“These new renewable energy targets send strong signals to energy markets and investment circles,” said Jennifer Morgan, Global Director, Climate Program, WRI.

“Combined with the Paris climate agreement, it’s clear that renewable energy is poised to surge forward in the next 15 years bringing clean and affordable power to millions of people worldwide.”

These economies are among many which have announced new renewables targets in the past 12 months ahead of a United Nations’ climate conference in Paris from Nov. 30 to Dec. 11 to fight global warming from 2020.

Canada and Russia, which are also among the world’s top 10 emitting countries, were not included in the study because they have not announced post-2020 renewable energy targets.

So far, plans submitted to the U.N. by around 150 countries to cut greenhouse gases will only slow climate change and not limit rising global temperatures to two degrees Celsius, a threshold seen by scientists as avoiding the worst effects of climate change.

(Editing by Mark Potter)
Read more at Reutershttp://www.reuters.com/article/2015/11/05/us-climatechange-renewables-idUSKCN0SU0YW20151105#QIRG1m840J5TUDM5.99