New solar cell may be most efficient in the world

July 13, 2017

Washington, Jul 13: Scientists have designed a new solar cell that converts direct sunlight to electricity with 44.5 per cent efficiency, and may potentially be the most efficient solar cell in the world.solar

The prototype integrates multiple cells stacked into a single device capable of capturing nearly all of the energy in the solar spectrum, researchers said.

The approach developed by researchers at George Washington University (GWU) in the US is different from the solar panels one might commonly see on rooftops or in fields.

The new device uses concentrator photovoltaic (CPV) panels that employ lenses to concentrate sunlight onto tiny, micro-scale solar cells.

Due to their small size - less than one millimetre square - solar cells utilising more sophisticated materials can be developed cost effectively, researchers said.

The stacked cell acts almost like a sieve for sunlight, with the specialised materials in each layer absorbing the energy of a specific set of wavelengths.

By the time the light is funnelled through the stack, just under half of the available energy has been converted into electricity. By comparison, the most common solar cell today converts only a quarter of the available energy into electricity.

"Around 99 per cent of the power contained in direct sunlight reaching the surface of Earth falls between wavelengths of 250 nanometres (nm) and 2,500 nm, but conventional materials for high-efficiency multi-junction solar cells cannot capture this entire spectral range," said Matthew Lumb, lead author of the study published in the journal Advanced Energy Materials.

"Our new device is able to unlock the energy stored in the long-wavelength photons, which are lost in conventional solar cells, and therefore provides a pathway to realising the ultimate multi-junction solar cell," said Lumb.

While scientists have worked towards more efficient solar cells for years, this approach has two novel aspects.

First, it uses a family of materials based on gallium antimonide (GaSb) substrates, which are usually found in applications for infra-red lasers and photodetectors. The novel GaSb-based solar cells are assembled into a stacked structure along with high efficiency solar cells grown on conventional substrates that capture shorter wavelength solar photons.

In addition, the stacking procedure uses a technique known as transfer-printing, which enables three dimensional assembly of these tiny devices with a high degree of precision.

This particular solar cell is very expensive, however researchers believe it was important to show the upper limit of what is possible in terms of efficiency.

Despite the current costs of the materials involved, the technique used to create the cells shows much promise, researchers said.

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Agencies
May 27,2020

Due to impacts of COVID-19, shipments of total mobile phones are forecast to decline 14.6% in 2020, while smartphone shipments will achieve a slightly slower decline of 13.7 % year over year to total 1.3 billion units this year, according to a Gartner forecast on Tuesday.

"While users have increased the use of their mobile phones to communicate with colleagues, work partners, friends and families during lockdowns, reduced disposable income will result in fewer consumers upgrading their phones," Ranjit Atwal, Senior Research Director at Gartner, said in a statement.

"As a result, phone lifetimes will extend from 2.5 years in 2018 to 2.7 years in 2020," said Atwal.

In 2020, affordable 5G phones were expected to be the catalyst to increase phone replacements, but now it is unlikely to be the case.

5G phones are now forecast to represent only 11% of total mobile phone shipments in 2020.

"The delayed delivery of some 5G flagship phones is an ongoing issue," said Annette Zimmermann, Research Vice President at Gartner.

"Moreover, the lack of 5G geographical coverage along with the increasing cost of the 5G phone contract will impact the choice of a 5G phone."

Overall, spending on 5G phones will be impacted in most regions apart from China, where continued investment in 5G infrastructure is expected, allowing providers in China to effectively market 5G phones.

The combined global shipments PCs, tablets and mobile phones are on pace to decline 13.6% in 2020, according to the forecast.

PC shipments are expected to decline 10.5% this year. Shipments of notebooks, tablets and Chromebooks are forecast to decline slower than the PC market overall in 2020.

"The forecasted decline in the PC market in particular could have been much worse," said Atwal.

"However, government lockdowns due to COVID-19 forced businesses and schools to enable millions of people to work from home and increase spending on new notebooks, Chromebooks and tablets for those workers. Education and government establishments also increased spending on those devices to facilitate e-learning."

Gartner said that 48 per cent of employees will likely work remotely at least part of the time after the COVID-19 pandemic, compared to 30 % pre-pandemic.

Overall, the work from home trend will make IT departments shift to more notebooks, tablets and Chrome devices for work.

"This trend combined with businesses required to create flexible business continuity plans will make business notebooks displace desk based PCs through 2021 and 2022," said Atwal.

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Agencies
June 18,2020

New Delhi, Jun 18: Vodafone Idea on Thursday told the Supreme Court that it has incurred Rs 1 lakh crore losses as it insisted it is not in a position to furnish bank guarantees.

A bench comprising Justices Arun Mishra, S. Abdul Nazeer, and M.R. Shah, taking up the adjusted gross revenue (AGR) matter through video conferencing, directed the telecom companies to submit their financial documents and books for the last 10 years.

Asking Vodafone if it was a foreign company, the bench said that how can the company say it would not furnish any bank guarantee.

"What if you fly away overnight in future without paying anything?" it asked.

Senior advocate Mukul Rohatgi, representing Vodafone Idea, denied his client is a completely foreign firm and cited before the bench its tie-ups and investments.

Vodafone owes over Rs 58,000 crore as AGR dues and so far, has paid close to Rs 7,000 crore.

Rohatgi contended before the court that the telecom company is in a tough situation, and cannot furnish any fresh bank guarantee, as profits have eluded the company in past many quarters. He submitted before the bench that Rs 15,000 crore bank guarantees are lying with the government, and his client's losses are over Rs 1 lakh crore.

"I cannot offer any more surety," he informed the bench.

Justice Mishra noted that this is public money and these dues should be recovered. "Do not tell us that you will pay if you were to make profits... the money must come," he noted.

Justice Shah observed that the telecom industry is the only industry which earned during the Covid-19 pandemic. "After all, this money will be used for public welfare", he said.

Rohatgi argued that his client would have to fold up if orders were issued to clear dues tomorrow. "11,000 employees will have to go without notice, as we cannot pay them," he added.

Senior advocate Abhishek Manu Singhvi, appearing for Bharti Airtel, contended before the court that out of Rs 21,000 crore AGR dues, the company has already deposited a sum of Rs 18,000 crore.

He argued that his client has given a bank guarantee, in excess of demand, to DoT, and supported the proposal for phased repayment of remaining AGR dues. He insisted that the company needs to sit down with the government and calculate the dues. Airtel owes Rs 25,976 crore after paying Rs 18,000 crore, as per the government.

Senior advocate Arvind Datar, representing Tata Telecom, informed the bench that his client has paid Rs 6,504 crore in AGR dues so far, and furnishing a bank guarantee may adversely impact investments in the sector.

The total AGR dues are close to Rs 1.5 lakh crore.

The top court will now take up the matter in the third week of July.

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Agencies
February 27,2020

Feb 27: With the window to submit comments on India's proposed personal data protection law closing on Tuesday, a period of anxious wait for final version of the Bill started for social media firms.

This comes even as global Internet companies have called on the government for improved transparency related to intermediary Guidelines (Amendment) Rules and allay fears about the prospect of increased surveillance and prompting a fragmentation of the Internet in India that would harm users.

As per the proposed amendments, an intermediary having over 50 lakh users in the country will have to be incorporated in India with a permanent registered office and address.

When required by lawful order, the intermediary shall, within 72 hours of communication, provide such information or assistance as asked for by any government agency or assistance concerning security of the state or cybersecurity.

This means that the government could pull down information provided by platforms such as Wikipedia, potentially hampering its functioning in India.

In the open letter to IT Minister Ravi Shankar Prasad, leading browser and software development platform like Mozilla, Microsoft-owned GitHub and Cloudflare earlier called for improved transparency by allowing the public an opportunity to see a final version of these amendments prior to their enactment.

According to a Business Insider report, Indian users may lose access to Wikipedia if the new intermediary rules for internet and social media companies are approved.

Since the rules would require the website to take down content deemed illegal by the government, it would require Wikipedia to show different content for different countries.

Anusha Alikhan, senior communications director for Wikimedia told Business Insider that the platform is built though languages and not geographies. Therefore, removing content from one country, while it is still visible to other country users may not work for the company’s model.

India is one of Wikipedia’s largest markets. Over 771 million Indian users accessed the site in just November 2019.

Also read: Explained: What is the Personal Data Protection Bill and why you should care

The Personal Data Protection Bill, 2019, which was introduced in Lok Sabha in the winter session last year, was referred to a Joint Parliamentary Committee (JPC) of both the Houses.

The government last month decided to seek views and suggestions on the Bill from individuals and associations and bodies concerned and the last date for submitting the comments was on Tuesday.

Prasad, while introducing the Personal Data Protection Bill, 2019, in the Lok Sabha on December 11, announced that the draft Bill empowers the government to ask companies including Facebook, Google and others for anonymised personal data and non-personal data.

There was a buzz when the Bill's latest version was introduced in the Lok Sabha, especially the provision seeking to allow the use of personal and non-personal data of users in some cases, especially when national security is involved.

Several legal experts red-flagged the issue and said the provision will give the government unaccounted access to personal data of users in the country.

In their submission to the JPC, several organisations also flagged that the power to collect non-personal and anonymised data by the government without notice and consent should not form part of the Bill because of issues regarding effective anonymisation and potential abuse.

"Clauses 35 and 36 of the Bill provide unbridled access to personal data to the Central Government by giving it powers to exempt its agencies from the application of the Bill on the basis of various broad worded grounds," SFLC.in, a New Delhi-based not-for-profit legal services organisation, commented.

The Software Alliance, also known as BSA, a trade group which includes tech giants such as Microsoft, IBM and Adobe, among others said that the current version of the privacy bill pose substantial challenges, including the sweeping new powers for the government to acquire non-personal data, restrictions on data transfers, and local storage requirements.

"We urge the Joint Parliamentary Committee, as it considers revisions to the Bill, to eliminate provisions concerning non-personal data from the Personal Data Protection Bill and to remove the data localisation requirements and restrictions on international data flows," said Venkatesh Krishnamoorthy, Country Manager-India, BSA.

The Personal Data Protection (PDP) Bill, 2019 draws its origins from the Justice B.N. Srikrishna Committee on data privacy, which produced a draft of legislation that was made public in 2018 ("the Srikrishna Bill").

The mandatory requirement for storing a mirror copy of all personal data in India as per Section 40 of the Srikrishna Bill has been done away with in the PDP Bill, 2019, meaning that companies like Facebook and Twitter would be able to store data of Indian users abroad if they so wish.

But the bill prohibits processing of sensitive personal data and critical personal data outside India.

What is more, what constitutes critical data has not been clearly defined.

As per the proposals, social media companies will have to modify their application as they are required to have a system in place by which a user can verify themselves.

So legal experts believe that some system to upload identification documents should be there and something like the Twitter blue tick mark should be there to identify verified accounts.

"The 2019 Bill introduces a new category of data fiduciaries called social media intermediaries ('SMIs'). SMIs are a subcategory of significant data fiduciaries ('SDFs') and will be notified by the Central government after due consultation with the DPA, or the Data Protection Authority. Clause 26(4) of the Bill defines SMIs as intermediaries who primarily or solely enable online interaction between two or more users," SFLC.in said.

"On a plain reading of the definition, online platforms like Facebook, Twitter, YouTube, TikTok, ShareChat and WhatsApp are likely to be notified as SMIs under the Bill," it added.

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