Software predicts power output for wind

By RenewableEnergyWorld.com


Substation Relay Protection Training

Our customized live online or in‑person group training can be delivered to your staff at your location.

  • Live Online
  • 12 hours Instructor-led
  • Group Training Available
Regular Price:
$699
Coupon Price:
$599
Reserve Your Seat Today
There's a storm brewing, the wind speed is picking up and you're asking yourself: Just how much electricity will a particular wind park produce in the next five days?

How much electricity will all the wind parks located in particular region, or even country, produce in the next few days for the national grid? Will the wind keep on blowing? And whereabouts exactly?

Thanks to a new system developed by a German university spin-off, it's now possible to obtain an accurate forecast of the energy output from wind parks for up to ten days in advance.

The Previento system, developed at Oldenburg University in northern Germany in cooperation with researchers from Denmark's Riso National Laboratory, can predict not only how much electricity a specific wind park in Germany will produce but also the total amount of electricity the 20,000 or so wind parks dotted around the country will generate in the coming days and with a high level of accuracy.

Armed with these predictions, Germany's grid operators can now calculate the amount of additional electricity they will need from fossil-fuel plants to compensate for troughs in wind output — and so ensure the expected power demand is covered reliably.

"The German electricity industry has to able to plan today how much electricity it will need tomorrow as well as how that electricity will be produced. That is what our system helps them to do," Dr. Matthias Lange from energy & meteo systems, the Oldenburg spin-off, said.

"Accurate predictions about wind power allow grid operators to save millions of euros through efficient scheduling," he added.

A system that can predict how much electricity is going to be available from wind power for the national grid has become so important in Germany because wind's share of the country's electricity generation is growing all the time, and reshaping the electricity industry.

Wind power accounted for 7.2 percent of Germany's total electricity consumption at the end of 2007 with 22,200 megawatts (MW) of installed capacity.

According to the German Wind Energy Association (BWE), installed capacity is set to double by 2020 with 45,000 MW installed on land and 10,000 MW offshore.

In fact, the BWE estimates that every fourth kilowatt hour of electricity will be coming from wind power within 12 years.

"The amount of wind power used today in Germany is so big that all the other types of power plants have to adapt themselves around the wind power output and increase or decrease their contribution depending on what wind does," said Lange.

Because Previento can give plenty of warning about big deviations and sudden peaks and troughs in wind power output, it also plays a big role in the regional energy spot markets. The amount of wind power entering the grid impacts electricity prices: the more wind power available, the lower the electricity price becomes, Lange explained. This is because less conventional energy has to be purchased by energy providers for the next few days to cover the expected demand.

The predictions are more accurate, the shorter the timeframe — but predictions for up to 10 days in advance are available, Lange said. The prediction error of the system is within 5 percent in 70 percent of the cases in Germany.

So what makes Previento's predictions so accurate?

According to Lange, the key is that the system was developed inside Oldenburg's physics department — and atmospheric physics as well as the shape of local terrain strongly influences the amount of electricity a wind park will produce.

The system calculates the amount of wind available at any particular location using a variety of weather models available from multiple weather services. The German Weather Services, for example, supplies information on wind speed, wind direction, pressure and a vertical temperature profile for rectangular grids with a resolution of 7 kilometers.

Previento processes this data and combines it with data about the features of local terrain of a wind park, such as the amount of wooded area or the bodies of water around a wind park to form an accurate estimation of the electricity output at any given time.

The system is proving a global hit with interest in it coming from Spain, Scandinavia, America, Canada and Ireland.

The system was developed in 2001 by the energy meteorology research group at the Carl von Ossietzky Universität Oldenburg and ForWind, the center for wind energy research based in Oldenburg. The energy & meteo spin-off company was founded in 2004, and is a pioneer in the new discipline of energy meteorology which puts weather forecasts at the service of renewable energy.

Related News

The City of Vancouver is hosting an ABB FIA Formula E World Championship race next year, organizers have announced

Vancouver Formula E 2022 delivers an all-electric, net-zero motorsport event in False Creek, featuring sustainability initiatives, clean mobility showcases, concerts, and tourism boosts, with major economic impact, jobs, and a climate action conference.

 

Key Points

A net-zero, all-electric race in False Creek, uniting EV motorsport with sustainability, concerts, and local jobs.

✅ Net-zero, all-electric FIA championship round in Canada

✅ False Creek street circuit with concerts and green mobility expo

✅ Projected $80M impact and thousands of local jobs

 

The City of Vancouver is hosting an ABB FIA Formula E World Championship race next year, organizers have announced, aligning with the city's EV-ready policy to accelerate adoption.

The all-electric race is being held in the city's False Creek neighbourhood over the 2022 July long weekend as green energy investments accelerate nationwide, according to promoter OSS Group Inc.

Earlier this year, Vancouver city council voted unanimously in support of a multi-day Formula E event that would include a conference on climate change and sustainability amid predicted EV-demand bottlenecks in B.C.

"Formula E is a win on so many levels, from being a net-zero event that supports sustainable transportation to being a huge boost for our hard-hit tourism sector, our residents, who can access rebates for home and workplace charging, and our local economy," Coun. Sarah Kirby-Yung said in a news release Thursday.

As the region advances sustainable mobility, B.C.'s EV charging expansion continues to lead the country.

The promoter said the Formula E race will bring $80 million in economic value and thousands of jobs to the city, with infrastructure like new EV chargers at YVR also underway, but did not provide any details on how it came to those estimates.

More details on the events surrounding the race, including planned concerts and other EV showcases like Everything Electric, are expected to be announced in the fall.

The last time a Formula E World Championship event came to Canada was the Montreal ePrix in 2017. Montreal Mayor Valerie Plante later cancelled planned Formula E events for 2018 and 2019, citing cost overruns and sponsorship troubles.

 

Related News

View more

Here are 3 ways to find out where your electricity comes from

US energy mix shows how the electric grid blends renewables, fossil fuels, nuclear, and hydro, varying by ISO/RTO markets, utilities, and state policies, affecting carbon emissions, pricing, reliability, and access.

 

Key Points

The US energy mix is the grid's source breakdown by region: fossil fuels, renewables, nuclear, and hydro.

✅ Check ISO or RTO dashboards for real-time generation by fuel source.

✅ Utilities may offer green power plans or RECs at modest premiums.

✅ Energy mix shifts with policy, pricing, and grid reliability needs.

 

There are few resources more important than energy. Sure, you may die if you don't eat for days. But your phone will die if you go too long without charging it. Energy feeds tech, the internet, city infrastructure, refrigerators, lights, and has evolved throughout U.S. history in profound ways. You get the idea. Yet unlike our other common needs, such as food, energy sources aren't exactly front of mind for most people. 

"I think a lot of people don't put a lot of bandwidth into thinking about this part of their lives," said Richard McMahon, the SVP of energy supply and finance at Edison Electric Institute, a trade group that represents investor-owned electric companies in the US. 

It makes sense. For most Americans, electricity is always there, and in many locations, there's not much of a choice involved, even as electricity demand is flat across the U.S. today. You sign up with a utility when you move into a new residence and pay your bills when they're due. 

But there's an important reality that indifference eschews: In 2018, a third of the energy-related carbon-dioxide emissions in the US came from the electric power sector, according to the US Energy Information Administration (EIA). 

A good chunk of that is from the residential sector, which consistently uses more energy than commercial customers, per EIA data.

Just as many people exercise choice when they eat, you typically also have a choice when it comes to your energy supply. That's not to say your current offering isn't what you want, or that switching will be easy or affordable, but "if you're a customer and want power with a certain attribute," McMahon said, "you can pretty much get it wherever you are." 

But first, you need to know the energy mix you have right now. As it turns out, it's not so straightforward. At all.

This brief guide may help. 

For some utility providers, you can find out if it publishes the energy mix online. Dominion Energy, which serves Idaho, North Carolina, Ohio, South Carolina, Utah, Virginia, West Virginia, and Wyoming, provides this information in a colored graphic. 

"Once you figure out who your utility is you can figure out what mix of resources they use," said Heidi Ratz, an electricity markets researcher at the World Resources Institute.

But not all utilities publish this information.

It has to do with their role in the grid and reflects utility industry trends in structure and markets. Some utility companies are vertically integrated; they generate power through nuclear plants or wind farms and distribute those electrons directly to their customers. Other utilities just distribute the power that different companies produce. 

Consider Consolidated Edison, or Con Ed, which distributes energy to parts of New York City. While reporting this story, Business Insider could not find information about the utility's energy mix online. When reached for comment, a spokesperson said, "we're indifferent to where it comes from."

That's because, in New York, distribution utilities like Con Ed often buy energy through a wholesale marketplace.

Take a look at this map. If you live in one of the colored regions, your electricity is sold on a wholesale market regulated by an organization called a regional transmission organization (RTO) or independent system operator (ISO). Distribution utilities like Con Ed often buy their energy through these markets, based on availability and cost, while raising questions about future utility revenue models as prices shift. 

Still, it's pretty easy to figure out where your energy comes from. Just look up the ISO or RTO website (such as NYISO or CAISO). Usually, these organizations will provide energy supply information in near-real time. 

That's exactly what Con Edison (which buys energy on the NYISO marketplace) suggested. As of Friday morning, roughly 40% of the energy on the market place was natural gas or other fossil fuels, 34% was nuclear, and about 22% was hydro. 

If you live in another region governed by an ISO or RTO, such as in most of California, you can do the same thing. Like NYISO, CAISO has a dashboard that shows (again, as of Friday morning) about 36% of the energy on the market comes from natural gas and more than 20% comes from renewables. 

In the map linked above, you'll notice that some of the ISOs and RTOs like MISO encompass enormous regions. That means that even if you figure out where the energy in your market comes from, it's not going to be geographically specific. But there are a couple of ways to drill down even further. 

The Environmental Protection Agency has a straightforward tool called Power Profiler. You can enter your zip code to see the fuel mix in your area. But it's not perfect. The data are from 2016 and, in some regions of the country like the upper Midwest, they aren't much more localized, and some import dirty electricity due to regional trading. 

The World Resources Institute also has a tool that allows you to see the electricity mix by state, based on 2017 data from EIA. These numbers represent power generation, not the electricity actually flowing into your sockets, but they offer a rough idea of what energy resources are operating in your state. 

One option is to check with your utility to see if it has a "green power" offering. Over 600 utilities across the country have one, according to the Climate Reality Project, though they often come at a slightly higher cost. It's typically on the scale of just a few more cents per kilowatt-hour. 

There are also independent, consumer-facing companies like Arcadia and Green Mountain Energy that allow you to source renewable energy, by virtually connecting you to community solar projects or purchasing Renewable Energy Certificates, or RECs, on your behalf, as America goes electric and more options emerge. 

"RECs measure an investment in a clean energy resource," Ratz said, in an email. "The goal of putting that resource on the grid is to push out the need for dirtier resources."

The good news: Even if you do nothing, your energy mix will get cleaner. Coal production has fallen to lows not seen since the 1980s, amid disruptions in coal and nuclear sectors that affect reliability and costs, while renewable electricity generation has doubled since 2008. So whether you like it or not, you'll be roped into the clean energy boom one way or another. 

 

Related News

View more

Metering Pilot projects may be good example for Ontario utilities

Ontario Electricity Pricing Pilot Projects explore alternative rates beyond time-of-use, with LDCs and the Ontario Energy Board testing dynamic pricing, demand management, smart-meter billing, and residential customer choice to enhance service and energy efficiency.

 

Key Points

Ontario LDC trials testing alternatives to time-of-use rates to improve billing, demand response, and efficiency.

✅ Data shared across LDCs and Ontario Energy Board provincewide

✅ Tests dynamic pricing, peak/off-peak plans, demand management

✅ Insights to enhance customer choice, bills, and energy savings

 

The results from three electricity pilot projects being offered in southern Ontario will be valuable to utility companies across the province.

Ontario Energy Minister Glenn Thibeault was in Barrie on Tuesday to announce the pilot projects, which will explore alternative pricing plans for electricity customers from three different utility companies, informed by the electricity cost allocation framework guiding rate design.

"Everyone in the industry is watching to see how the pilots deliver.", said Wendy Watson, director of communications for Greater Sudbury Utilities.

"The data will be shared will all the LDCs [local distribution companies] in the province, and probably beyond...because the industry tends to share that kind of information."

Most electricity customers in the province are billed using time-of-use rates, including options like the ultra-low overnight rates that lower costs during off-peak periods, where the cost of electricity varies depending on demand.

The Ontario Energy Board said in a media release that the projects will give residential customers more choice in how much they pay for electricity at different times, reflecting changes for Ontario electricity consumers that expand plan options.

Pilot projects can help improve service

Watson says these kinds of projects give LDCs the chance to experiment and explore new ways of delivering their service, including demand-response initiatives like the Peak Perks program that encourage conservation.

"Any pilot project is a great way to see if in practice if the theory proves out, so I think it's great that the province is supporting these LDCs," she says.

GSU recently completed its own pilot project, the Home Energy Assessment and Retrofit (HEAR) program, which focused on customers who use electric baseboards to heat their homes, amid broader provincial support for electric bills to ease costs."We installed some measures, like programmable thermostats and a few other pieces of equipment into their house," Watson says. "We also made some recommendations about other things that they could do to make their homes more energy efficient."

At the end of the program, GSU provided customers with a report so that they could the see the overall impact on their energy consumption.

Watson says a report on the results of the HEAR program will be released in the near future, for other LDCs interested in new ways to improve their service.

"We think it's incumbent on every LDC...to see what ideas that they can come up with and get approved so they can best serve their customers."

 

Related News

View more

A tidal project in Scottish waters just generated enough electricity to power nearly 4,000 homes

MeyGen Tidal Stream Project delivers record 13.8 GWh to Scotland's grid, showcasing renewable ocean energy. Simec Atlantis Energy's 6 MW array of tidal turbines advances EU power goals and plans an ocean-powered data center.

 

Key Points

A Scottish tidal energy array exporting record power, using four 1.5 MW turbines and driving renewable innovation.

✅ Delivered 13.8 GWh to the grid in 2019, a project record.

✅ Four 1.5 MW turbines in Phase 1A, 6 MW installed.

✅ Plans include an ocean-powered data center near site.

 

A tidal power project in waters off the north coast of Scotland, where Scotland’s wind farms also deliver significant output, sent more than 13.8 gigawatt hours (GWh) of electricity to the grid last year, according to an operational update issued Monday. This figure – a record – almost doubled the previous high of 7.4 GWh in 2018.

In total, the MeyGen tidal stream array has now exported more than 25.5 GWh of electricity to the grid since the start of 2017, according to owners Simec Atlantis Energy. Phase 1A of the project is made up of four 1.5 megawatt (MW) turbines.

The 13.8 GWh of electricity exported in 2019 equates to the average yearly electricity consumption of roughly 3,800 “typical” homes in the U.K., where wind power records have been set recently, according to the company, with revenue generation amounting to £3.9 million ($5.09 million).

Onshore maintenance is now set to be carried out on the AR1500 turbine used by the scheme, with Atlantis aiming to redeploy the technology in spring.

In addition to the production of electricity, Atlantis is also planning to develop an “ocean-powered data centre” near the MeyGen project.

The European Commission has described “ocean energy” as being both abundant and renewable, and milestones like the biggest offshore windfarm starting U.K. supply underscore wider momentum, too. It’s estimated that ocean energy could potentially contribute roughly 10% of the European Union’s power demand by the year 2050, according to the Commission.

While tidal power has been around for decades — EDF’s 240 MW La Rance Tidal Power Plant in France was built as far back as 1966, and the country’s first offshore wind turbine has begun producing electricity — recent years have seen a number of new projects take shape.

In December last year, Scottish tidal energy business Nova Innovation was issued with a permit to develop a project in Nova Scotia, Canada, aiming to harness the Bay of Fundy tides in the region further.

In an announcement at the time, the firm said a total of 15 tidal stream turbines would be installed by the year 2023. The project, according to the firm, will produce enough electricity to power 600 homes, as companies like Sustainable Marine begin delivering tidal energy to the Nova Scotia grid.

Elsewhere, a business called Orbital Marine Power is developing what it describes as the world’s most powerful tidal turbine, with grid-supplied output already demonstrated.

The company says the turbine will have a swept area of more than 600 square meters and be able to generate “over 2 MW from tidal stream resources.” It will use a 72-meter-long “floating superstructure” to support two 1 MW turbines.

 

Related News

View more

American Households Struggle with Sky-High Energy Bills During Extreme Summer Heat

US Summer Energy Bills Crisis is driven by record heatwaves, soaring electricity prices, AC cooling demand, energy poverty risks, and LIHEAP relief, straining low-income households, vulnerable seniors, and budgets amid volatile utilities and peak demand.

 

Key Points

Rising household energy costs from extreme heat, higher electricity prices, and AC demand, straining vulnerable families.

✅ Record heatwaves drive peak electricity and cooling loads

✅ Tiered rates and volatile markets inflate utility bills

✅ LIHEAP aid and cooling centers offer short-term relief

 

As the sweltering heat of summer continues to grip much of the United States, American households are grappling with a staggering rise in energy bills. The combination of record-breaking temperatures and rising electricity prices is placing an unprecedented financial strain on families, raising concerns about the long-term impact on household budgets and overall well-being.

Record Heat and Energy Consumption

This summer has witnessed some of the hottest temperatures on record across the country. With many regions experiencing prolonged heatwaves, the demand for air conditioning and cooling systems has surged amid unprecedented electricity demand across parts of the U.S. The increased use of these energy-intensive appliances has led to a sharp rise in electricity consumption, which, combined with elevated energy prices, has pushed household energy bills to new heights.

The situation is particularly dire for households that are already struggling financially. Many families are facing energy bills that are not only higher than usual but are reaching levels that are unsustainable, underscoring electricity struggles for thousands of families across the country. This has prompted concerns about the potential for energy poverty, where individuals are forced to make difficult choices between paying for essential services and covering other necessary expenses.

Impact on Low-Income and Vulnerable Households

Low-income households and vulnerable populations are disproportionately affected by these soaring energy costs. For many, the financial burden of high energy bills is compounded by energy insecurity during the pandemic and other economic pressures, such as rising food prices and stagnant wages. The strain of paying for electricity during extreme heat can lead to tough decisions, including cutting back on other essential needs like healthcare or education.

Moreover, the heat itself poses a serious health risk, particularly for the elderly, children, and individuals with pre-existing health conditions. High temperatures can exacerbate conditions such as cardiovascular and respiratory illnesses, making the need for reliable cooling even more critical. For those struggling to afford adequate cooling, the risk of heat-related illnesses and fatalities increases significantly.

Utilities and Energy Pricing

The sharp rise in energy bills can be attributed to several factors, including higher costs of electricity production and distribution. The ongoing transition to cleaner energy sources, while necessary for long-term environmental sustainability, has introduced short-term volatility in energy markets. Additionally, power-company supply chain crises and increased demand during peak summer months have contributed to higher prices.

Utilities are often criticized for their pricing structures, which can be complex and opaque. Some regions, including areas where California electricity bills soar under scrutiny, use tiered pricing models that charge higher rates as energy consumption increases. This can disproportionately impact households that need to use more energy during extreme heat, further exacerbating financial strain.

Government and Community Response

In response to the crisis, various government and community initiatives are being rolled out to provide relief. Federal and state programs aimed at assisting low-income households with energy costs are being expanded. These programs, such as the Low-Income Home Energy Assistance Program (LIHEAP), offer financial assistance to help with utility bills, but demand often outstrips available resources.

Local community organizations are also stepping in to offer support. Initiatives include distributing fans and portable air conditioners, providing temporary cooling centers, and offering financial assistance to help cover energy costs. These efforts are crucial in helping to mitigate the immediate impact of high energy bills on vulnerable households.

Long-Term Solutions and Sustainability

The current crisis highlights the need for long-term solutions to address both the causes and consequences of high energy costs. Investing in energy efficiency and renewable energy technologies can help reduce the overall demand for electricity and lower long-term costs. Improvements in building insulation, the adoption of energy-efficient appliances, and advancements in smart grid technologies to prevent summer power outages are all essential components of a sustainable energy future.

Furthermore, addressing income inequality and supporting economic stability are critical to ensuring that all households can manage their energy needs without facing financial hardship. Policymakers will need to consider a range of strategies, including financial support programs, regulatory reforms, and infrastructure investments, to create a more equitable and resilient energy system.

Conclusion

As American households endure the double burden of extreme summer heat and skyrocketing energy bills, the need for immediate relief and long-term solutions has never been clearer. The current crisis serves as a reminder of the broader challenges facing the nation’s energy system and the importance of addressing both short-term needs and long-term sustainability. By investing in efficient technologies, supporting vulnerable populations, and developing resilient infrastructure, the U.S. can work towards a future where energy costs are manageable, and everyone has access to the resources they need to stay safe and comfortable.

 

Related News

View more

British Columbia Fuels Up for the Future with $900 Million Hydrogen Project

H2 Gateway Hydrogen Network accelerates clean energy in B.C., building electrolysis plants and hydrogen fueling stations for zero-emission vehicles, heavy-duty trucks, and long-haul transit, supporting decarbonization, green hydrogen supply, and infrastructure investment.

 

Key Points

A $900M B.C. initiative by HTEC to build electrolysis plants and 20 hydrogen fueling stations for zero-emission transport.

✅ $900M project with HTEC, CIB, and B.C. government

✅ 3 electrolysis plants plus byproduct liquefaction in North Vancouver

✅ Up to 20 stations; 14 for heavy-duty vehicles in B.C. and Alberta

 

British Columbia is taking a significant step towards a cleaner future with a brand new $900 million project. This initiative, spearheaded by hydrogen company HTEC and supported by the CIB in B.C. and the B.C. government, aims to establish a comprehensive hydrogen network across the province. This network will encompass both hydrogen production plants and fueling stations, marking a major leap in developing hydrogen infrastructure in B.C.

The project, dubbed "H2 Gateway," boasts several key components. At its core lies the construction of three brand new electrolysis hydrogen production plants. These facilities will be strategically located in Burnaby, Nanaimo, and Prince George, ensuring a wide distribution of hydrogen fuel. An additional facility in North Vancouver will focus on liquefying byproduct hydrogen, maximizing resource efficiency.

The most visible aspect of H2 Gateway will undoubtedly be the network of hydrogen fueling stations. The project envisions up to 20 stations spread across British Columbia and Alberta, complementing the province's Electric Highway build-out, with 18 being situated within B.C. itself. This extensive network will significantly enhance the accessibility of hydrogen fuel, making it a more viable option for motorists. Notably, 14 of these stations will be designed to handle heavy-duty vehicles, catering to the transportation sector's clean energy needs.

The economic and environmental benefits of H2 Gateway are undeniable. The project is expected to generate nearly 300 jobs, aligning with recent grid job creation efforts, providing a much-needed boost to the B.C. economy. More importantly, the widespread adoption of hydrogen fuel promises significant reductions in greenhouse gas emissions. Hydrogen-powered vehicles produce zero tailpipe emissions, making them a crucial tool in combating climate change.

British Columbia's investment in hydrogen infrastructure aligns with a global trend. As countries strive to achieve ambitious climate goals, hydrogen is increasingly viewed as a promising clean energy source. Hydrogen fuel cells offer several advantages over traditional electric vehicles, and while B.C. leads the country in going electric, they boast longer driving ranges and shorter refueling times, making them particularly attractive for long-distance travel and heavy-duty applications.

While H2 Gateway represents a significant step forward, challenges remain. The production of clean hydrogen, often achieved through electrolysis using renewable energy sources, faces power supply challenges and requires substantial initial investment. Additionally, the number of hydrogen-powered vehicles on the road is still relatively low.

However, projects like H2 Gateway are crucial in overcoming these hurdles. By creating a robust hydrogen infrastructure, B.C. is sending a strong signal to the industry and, alongside BC Hydro's EV charging expansion across southern B.C., is building a comprehensive clean transportation network. This investment will not only benefit the environment but also incentivize the development and adoption of hydrogen-powered vehicles. As the technology matures and production costs decrease, hydrogen fuel has the potential to revolutionize transportation and play a key role in a sustainable future.

The road ahead for hydrogen may not be entirely smooth, but British Columbia's commitment to H2 Gateway demonstrates a clear vision. By investing in clean energy infrastructure, the province is not only positioning itself as a leader in the fight against climate change, with Canada and B.C. investing in green energy solutions to accelerate progress, but also paving the way for a more sustainable transportation landscape.

 

Related News

View more

Sign Up for Electricity Forum’s Newsletter

Stay informed with our FREE Newsletter — get the latest news, breakthrough technologies, and expert insights, delivered straight to your inbox.

Electricity Today T&D Magazine Subscribe for FREE

Stay informed with the latest T&D policies and technologies.
  • Timely insights from industry experts
  • Practical solutions T&D engineers
  • Free access to every issue

Download the 2025 Electrical Training Catalog

Explore 50+ live, expert-led electrical training courses –

  • Interactive
  • Flexible
  • CEU-cerified