Ice sheets in Greenland are melting so rapidly due to high temperatures in the Arctic that the amount of ice melt from Tuesday was enough to cover all of Florida in two inches of water, according to the researchers at Polar Portal.
A massive ice melting event is taking place in #Greenland, according to @PolarPortal It would be enough to cover F… https://t.co/kZdBLFjDQ6— World Meteorological Organization (@World Meteorological Organization)1627548056.0
Greenland has lost 18.4 billion tons of surface mass since last Sunday. While not as bad as 2019, this is the third instance of extreme melting in the past decade and the scientists say the area of land melting is larger this time.
"In the past decade, we've already seen that surface melting in Greenland has become both more severe and more erratic," Thomas Slater, a glaciologist at the University of Leeds told CNN. "As the atmosphere continues to warm over Greenland, events such as yesterday's extreme melting will become more frequent."
As reported by CNN:
In 2019, Greenland shed roughly 532 billion tons of ice into the sea. During that year, an unexpectedly hot spring and a July heat wave caused almost the entire ice sheet's surface to begin melting. Global sea level rose permanently by 1.5 millimeters as a result.
As Greenland's surface continues to thaw, Slater said coastal cities around the world are vulnerable to storm-surge flooding, especially when extreme weather coincides with high tides. Melting from Greenland is expected to raise global sea level between 2 and 10 centimeters by the end of the century, he added.
"While such events are concerning, the science is clear," Slater said. "Meaningful climate targets and action can still limit how much the global sea level will rise this century, reducing the damage done by severe flooding to people and infrastructure around the world."
For a deeper dive:
- New Study Changes Understanding of How Greenland's Ice Melts ... ›
- Greenland and Antarctica Already Melting at 'Worst-Case-Scenario ... ›
The Whatcom County Council in Washington state has unanimously passed permanent land-use policies that ban new fossil fuel infrastructure, becoming the first in the U.S. to pass such a measure.
The ordinance prohibits the construction of new refineries or coal facilities and places more restrictions on expansion of fossil fuel facilities at Cherry Point, such as requiring offsets for greenhouse gases emitted from any expansions and rigorous environmental review.
Whatcom is currently polluted by two of Washington's five oil refineries, and five years ago saw the cancellation of the country's largest planned coal export facility due to concerns from the Lummi Tribe around fishing treaty rights.
"What's been happening in Whatcom County for the last 10 years and in the state and Oregon is that people have been saying no to these new proposals coming forward one by one by one," said Matt Krogh, director of the Safe Cities campaign for Stand.earth. "And people are winning."
For a deeper dive:
- Existing fossil fuel plants will push the world across a dangerous ... ›
- Vancouver council puts freeze on new fossil fuel infrastructure - The ... ›
- Washington's Port Of Vancouver Says No To New Fossil Fuel Projects ›
- County in Washington state becomes first in the US to ban new fossil ... ›
- Washington State's Largest County Just Banned New ... - 350.org ›
Making the switch to solar energy can help you lower or even eliminate your monthly electric bills while reducing your carbon footprint. However, before installing a clean energy system in your home, you must first answer an important question: "How many solar panels do I need?"
To accurately calculate the ideal number of solar panels for your home, you'll need a professional assessment. However, you can estimate the size and cost of the system based on your electricity bills, energy needs and available roof space. This article will tell you how.
If you make a purchase using the links included, we may earn commission.
Factors That Influence How Many Solar Panels You Need
To determine how many solar panels are needed to power a house, several factors must be considered. For example, if there are two identical homes powered by solar energy in California and New York, with exactly the same energy usage, the California home will need fewer solar panels because the state gets more sunshine.
The following are some of the most important factors to consider when figuring out many solar panels you need:
Size of Your Home and Available Roof Space
Larger homes tend to consume more electricity, and they generally need more solar panels. However, they also have the extra roof space necessary for larger solar panel installations. There may be exceptions to this rule — for example, a 2,000-square-foot home with new Energy Star appliances may consume less power than a 1,200-square-foot home with older, less-efficient devices.
When it comes to installation, solar panels can be placed on many types of surfaces. However, your roof conditions may limit the number of solar panels your home can handle.
For example, if you have a chimney, rooftop air conditioning unit or skylight, you'll have to place panels around these fixtures. Similarly, roof areas that are covered by shadows are not suitable for panels. Also, most top solar companies will not work on asbestos roofs due to the potential health risks for installers.
Amount of Direct Sunlight in Your Area
Where there is more sunlight available, there is more energy that can be converted into electricity. The yearly output of each solar panel is higher in states like Arizona or New Mexico, which get a larger amount of sunlight than less sunny regions like New England.
The World Bank has created solar radiation maps for over 200 countries and regions, including the U.S. The map below can give you an idea of the sunshine available in your location. Keep in mind that homes in sunnier regions will generally need fewer solar panels.
© 2020 The World Bank, Source: Global Solar Atlas 2.0, Solar resource data: Solargis.
Number of Residents and Amount of Energy You Use
Households with more members normally use a higher amount of electricity, and this also means they need more solar panels to increase energy production.
Electricity usage is a very important factor, as it determines how much power must be generated by your solar panel system. If your home uses 12,000 kilowatt-hours (kWh) per year and you want to go 100% solar, your system must be capable of generating that amount of power.
Type of Solar Panel and Efficiency Rating
High-efficiency panels can deliver more watts per square foot, which means you need to purchase fewer of them to reach your electricity generation target. There are three main types of solar panels: monocrystalline, polycrystalline and thin-film. In general, monocrystalline panels are the most efficient solar panels, followed closely by polycrystalline panels. Thin-film panels are the least efficient.
How to Estimate the Number of Solar Panels You Need
So, based on these factors, how many solar panels power a home? To roughly determine how many solar panels you need without a professional assessment, you'll need to figure out two basic things: how much energy you use and how much energy your panels will produce.
According to the latest data from the U.S. Energy Information Administration (EIA), the average American home uses 10,649 kWh of energy per year. However, this varies depending on the state. For example:
- Louisiana homes have the highest average consumption, at 14,787 kWh per year.
- Hawaii homes have the lowest average consumption, at 6,298 kWh per year.
To more closely estimate how much energy you use annually, add up the kWh reported on your last 12 power bills. These numbers will fluctuate based on factors like the size of your home, the number of residents, your electricity consumption habits and the energy efficiency rating of your home devices.
Solar Panel Specific Yield
After you determine how many kWh of electricity your home uses annually, you'll want to figure out how many kWh are produced by each of your solar panels during a year. This will depend on the specific type of solar panel, roof conditions and local peak sunlight hours.
In the solar power industry, a common metric used to estimate system capacity is "specific yield" or "specific production." This can be defined as the annual kWh of energy produced for each kilowatt of solar capacity installed. Specific yield has much to do with the amount of sunlight available in your location.
You can get a better idea of the specific yield that can be achieved in your location by checking reliable sources like the World Bank solar maps or the solar radiation database from the National Renewable Energy Laboratory.
To estimate how many kW are needed to run a house, you can divide your annual kWh consumption by the specific yield per kilowatt of solar capacity. For example, if your home needs 15,000 kWh of energy per year, and solar panels have a specific yield of 1,500 kW/kW in your location, you will need a system size of around 10 kilowatts.
Paradise Energy Solutions has also come up with a general formula to roughly ballpark the solar panel system size you need. You can simply divide your annual kWh by 1,200 and you will get the kilowatts of solar capacity needed. So, if the energy consumption reported on your last 12 power bills adds up to 24,000 kWh, you'll need a 20 kW system (24,000 / 1,200 = 20).
So, How Many Solar Panels Do I Need?
Once you know the system size you need, you can check your panel wattage to figure how many panels to purchase for your solar array. Multiply your system size by 1,000 to obtain watts, then divide this by the individual wattage of each solar panel.
Most of the best solar panels on the market have an output of around 330W to 360W each. The output of less efficient panels can be as low as 250W.
So, if you need a 10-kW solar installation and you're buying solar panels that have an output of 340W, you'll need 30 panels. Your formula will look like this: 10,000W / 340W = 29.4 panels.
If you use lower-efficiency 250-watt solar panels, you'll need 40 of them (10,000W / 250W = 40) panels.
Keep in mind that, although the cost of solar panels is lower if you choose a lower-efficiency model over a pricier high-efficiency one, the total amount you pay for your solar energy system may come out to be the same or higher because you'll have to buy more panels.
How Much Roof Space Do You Need for a Home Solar System?
After you estimate how many solar panels power a house, the next step is calculating the roof area needed for their installation. The exact dimensions may change slightly depending on the manufacturer, but a typical solar panel for residential use measures 65 inches by 39 inches, or 17.6 square feet. You will need 528 square feet of roof space to install 30 panels, and 704 square feet to install 40.
In addition to having the required space for solar panels, you'll also need a roof structure that supports their weight. A home solar panel weighs around 20 kilograms (44 pounds), which means that 30 of them will add around 600 kilograms (1,323 pounds) to your roof.
You will notice that some solar panels are described as residential, while others are described as commercial. Residential panels have 60 individual solar cells, while commercial panels have 72 cells, but both types will work in any building. Here are a few key differences:
- Commercial solar panels produce around 20% more energy, thanks to their extra cells.
- Commercial panels are also more expensive, as well as 20% larger and heavier.
- Residential 60-cell solar panels are easier to handle in home installations, which saves on labor, and their smaller size helps when roof dimensions are limited.
Some of the latest solar panel designs have half-cells with a higher efficiency, which means they have 120 cells instead of 60 (or 144 instead of 72). However, this doesn't change the dimensions of the panels.
Conclusion: Are Solar Panels Worth it for Your Home?
Solar panels produce no carbon emissions while operating. However, the EIA estimates fossil fuels still produce around 60% of the electricity delivered by U.S. power grids.
Although the initial investment in solar panels is steep, renewable energy systems make sense financially for many homeowners. According to the Department of Energy, they have a typical payback period of about 10 years, while their rated service life is up to 30 years. After recovering your initial investment, you will have a source of clean and free electricity for about two decades.
Plus, even if you have a large home or find you need more solar panels than you initially thought you would, keep in mind that there are both federal and local tax credits, rebates and other incentives to help you save on your solar power system.
To get a free, no-obligation quote and see how much a solar panel system would cost for your home, fill out the 30-second form below.
One part of President's Biden's infrastructure plan, a Civilian Climate Corps (CCC), could help places like storm-battered Lake Charles, Lousiana recover from extreme weather and prepare for future storms, Rolling Stone reports.
Many residents in Lake Charles are still recovering from Hurricanes Laura and Delta which hit the region last year, even as a new hurricane season begins. Currently, many in the region are relying on nonprofits and the federally funded, voluntary civil society program AmeriCorp to recover, as FEMA aid has been slow or nonexistent.
The CCC, which is based on the New Deal-era Civilian Conservation Corps, could help. Among other things, the program would put people to work restoring natural environments. In Lake Charles and coastal communities like it, restoring wetlands not only improves the natural habitat, but also can also serve as a buffer to absorb hurricane storm surge. At the funding level proposed in Biden's plan, the CCC would operate on a much smaller scale than the original Civilian Conservation Corps, employing around 200,000 people.
'However, there are several plans from Congressional Democrats calling for a more robust program that focuses on environmental justice and calls for investments in local-led adaptation projects. In May, members of the Sunrise Movement marched from New Orleans to Houston to highlight the potential of a CCC along the Gulf Coast. The fossil fuel industry supports up to 10 percent of jobs in Louisiana and even more in Lake Charles, so a program that offers employment would be welcome in the region.
"People feel forced to choose between putting food on their table and getting rid of the petrochemical plants," said Jenna Hanes, who marched with Sunrise. But a CCC would mean "workers can gain skills for the future, that aren't in an industry that's going to eventually die."
For a deeper dive:
- Biden Signs Sweeping Executive Orders on Climate and Science ... ›
- Sunrise Movement Launches Campaign for Guaranteed Jobs ... ›
The U.S. Environmental Protection Agency (EPA) announced Monday it is kicking off a new rulemaking process to pass stricter requirements for how coal power plants dispose of wastewater, undoing a major rollback implemented in the last year of the Trump administration.
Wastewater pollution from coal plants is poured into nearby rivers and streams and often contains toxic metals including arsenic, lead and mercury, which seriously harm marine life and have been linked to cancer, heart disease and other health problems.
Despite the change, the Biden administration said it does not plan to immediately reinstate the stricter requirements that were in effect before the rollback, and instead will allow the current system to stay in place while working to strengthen those rules.
The administration said it feared asking a court to revert back to the pre-Trump standard, put in place by former President Obama in 2015, because it could result in reverting to a previous, even more lax 1982 standard. However, by not enforcing stricter rules now, toxic wastewater can continue flowing into waterways for several more years.
"If their timeline is 2024, that's four years of damage," Brett Hartl, government affairs director at the Center for Biological Diversity, told the Washington post. "The industry is getting the better end of the deal out of this."
As reported by Courthouse News:
Under the new proposed EPA rule, coal power plants that use steam to generate electricity will be expected to install equipment that can better treat heavy metals, but the agency's notice is otherwise short on details. It does, however, say the rule will bring the agency in line with an executive order President Joe Biden signed in January.
Less than a day into his first term, Biden directed all federal agencies to review rules issued in the last four years under former President Donald Trump. Specifically, he asked agencies to assess whether those rules are consistent with the new administration's policy to "listen to science, improve public health and protect the environment, [ensure] access to clean air and water, [limit] exposure to dangerous chemicals and pesticides, [hold] polluters accountable" and reduce greenhouse gases while bolstering climate change resilience.
For a deeper dive:
- Biden Has Pledged to Advance Environmental Justice – Here's How ... ›
- Biden's EPA Pick Michael Regan Urged to Address Environmental ... ›
- 12 Trump Attacks on the Environment Since the Election - EcoWatch ›
Lake Powell fell to just 33% capacity Monday, marking the lowest level on record, in large part due to a climate-change driven drought in the region.
The reservoir, which is the country's second largest, is fed by the Colorado River and provides water for more than 40 million people across the region, including farmers, ranchers and native communities. Reduced snowpack, dry winters, and extreme heat are all worsening the region's megadrought and contributing to the reservoir's decline.
Lake Mead, another critical reservoir along the Colorado River, also reached historic lows last month. The Colorado River's flow has decreased 20% over the past century, half of which was due to climate change, and it could decrease by as much as 30% come mid-century. The low levels at both Lake Mead and Lake Powell are threatening the ability of the Glen Canyon Dam, a hydroelectric power plant, to supply power to several Western states.
Federal officials are expected to declare a water shortage on the Colorado River for the first time next month, triggering cutbacks next year in Arizona and Nevada.
"Over time, cities are going to need to conserve more and more water, and that doesn't get any easier with climate change," John Fleck, the director of the Water Resources Program at the University of New Mexico, told CNN.
For a deeper dive:
- America's Two Largest Water Reservoirs at Record Lows - EcoWatch ›
- Remarkable Drop in Colorado River Water Use Sign of Climate ... ›
- Drought-Stricken Colorado River Basin Could See Additional 20 ... ›
The 2020 Summer Olympics kicked off in Tokyo on Friday and there are already signs the toughest part of the competition may just be the extreme heat and humidity in what is expected to be the hottest Olympics on record.
Temperatures in Tokyo this time of year are usually in the high 80's, but a heat wave is pushing temperatures into the 90s. The heat index on Saturday made it feel like 100°F and humidity levels were above 80% on Sunday. Temperatures in July and August are 5.15°F/2.7°C warmer than they were last time Tokyo hosted the games in 1964, and on average, there are eight more days of 95-plus-degree weather.
Athletes are feeling the heat already: ahead of the Opening Ceremony on Friday, Russian Archer Svetlana Gomboeva collapsed during a qualifying event due to the heat. The Tennis tournament, which began Saturday, was also affected by the heat, as Russian player Anastasia Pavlyuchenkova required a medical timeout after feeling dizzy due to the heat. Then, several athletes participating in the triathlon, which finished Monday morning, had to be helped off the track due to overheating.
Extreme heat is now the deadliest weather event, and it is only getting worse as the planet continues warming. Despite this, currently, the International Olympic Committee doesn't take climate change into consideration when selecting host cities. Japan's proposal to host the 2020 games, for example, claimed "this period provides an ideal climate for athletes to perform their best" because of its "many days of mild and sunny weather."
For a deeper dive:
Overview: The Wall Street Journal, Popular Science; Weather: NBC News, Axios, The Washington Post; Gomboeva: Yahoo, Reuters, AP; Tennis: Reuters, AP, Insider; Health: Vox; Commentary: Dan Wetzel, Yahoo
- The Health Risks of Our Sweltering Summers - EcoWatch ›
- 10 Ways to Tell if You're Dehydrated - EcoWatch ›
In 2001, the IPCC's Third Assessment warned the greatest increases in heat stress were expected in "mid- to high-latitude (temperate) cities, especially in populations with non-adapted architecture and limited air conditioning." The scientists wrote at the time, "A number of U.S. cities would experience, on average, several hundred extra deaths each summer."
This year's June heat wave killed nearly 800 people in the usually-temperate region where few live in homes with air conditioning. That heat wave would have been "virtually impossible" without human-caused climate change.
For a deeper dive:
- Record-Breaking Heat Is a Clear Sign of Climate Change - EcoWatch ›
- North America Just Experienced Its Hottest June on Record ... ›
- 17 States Under Heat Alerts as Fifth Summer Heat Wave in the U.S. Begins ›
New York City's air quality was the worst in the world on Tuesday, posing a danger to everyone, not just groups considered more vulnerable than the general population. Even thinned by its 2,500 mile journey across the continent, smoke was so thick George Pope, a professor of earth and environmental studies at Montclair State University, couldn't see Manhattan from his New Jersey office.
"You can pretty much always see the skyline, at least a silhouette, if it's a hazy day," he told The Guardian. "This is, like, this is unprecedented." Nearly 80 large wildfires have burned more than 1.3 million acres across 13 states so far this year.
As reported by The Associated Press:
"These fires are going to be burning all summer," said University of Washington wildfire smoke expert Dan Jaffe. "In terms of bad air quality, everywhere in the country is to going to be worse than average this year."
Growing scientific research points to potential long-term health damage from breathing in microscopic particles of smoke. Authorities have scrambled to better protect people from the harmful effects but face challenges in communicating risk to vulnerable communities and people who live very far away from burning forests.
For a deeper dive:
Air quality: The Guardian, AP, Axios, Today Show, The Hill; Fires: Wall Street Journal, USA Today, The Hill; Health risks: AP explainer; Photos: Buzzfeed; Climate Signals background: 2021 Western wildfire season
- What's in Wildfire Smoke, and How Bad Is It for Your Lungs ... ›
- Smoke From Western Wildfires to Spread as Far as New York ... ›
More than two dozen people have been killed by catastrophic flash flooding in central China in recent days.
At least a dozen people drowned in the subway in Zhengzhou, Henan province, and about 100,000 people have been evacuated. Social media videos showed extreme flooding that turned cars into bathtub toys — as well as the harrowing rescue of 150 children and teachers from a flooded kindergarten.
The city was deluged by 24.3" (617.1mm) of rain — 96% of its annual average — in just three days from Saturday to Tuesday. The extreme rainfall, and the severe heatwaves that strained the province's electrical grid just days prior, are both clear signals of the climate crisis, caused by the extraction and combustion of fossil fuels.
"Such extreme weather events will likely become more frequent in the future," Johnny Chan, a professor of atmospheric science at City University of Hong Kong, told Reuters.
As reported by The Washington Post:
Experts and environmental organizations have connected the increase in severe weather events to climate change and China's rapid urbanization. The environmental advocacy organization Greenpeace warned last week that China's cities would face hotter summers and wetter rainy seasons because of climate change. Those conditions could cause more dangerous heat waves and heavier flooding in urban areas, Liu Junyan, the climate and energy project leader for Greenpeace in Beijing, told Al Jazeera.
The floods in Henan follow a string of unusually severe heat waves, floods and fires across the world in recent weeks. Flooding in Germany last week killed at least 165 people, and Canada and the Pacific Northwest have seen record-breaking heat and forest fires.
For a deeper dive:
Reuters, The New York Times, The Washington Post, BBC, The Guardian, France24, Al Jazeera, Bloomberg; Recent heatwaves: Bloomberg; Climate Signals background: Extreme precipitation increase; Extreme heat and heatwaves
Employment in renewable energy and battery-related sectors was far more resilient to the shock of the novel coronavirus pandemic, according to an annual DOE report released Monday.
Overall, one in 10 U.S. energy workers lost their jobs in 2020, with oil and gas workers hit hardest despite billions in bailouts and substantial payouts to executives. Wind energy employment grew by nearly 2%. Jobs in the electric and hybrid-electric vehicle sectors grew by 8% and 6% respectively, and battery storage jobs also increased.
"While we do have work to do to make our energy sector more robust, we also have a lot of work to do in making our energy sector look like America and to make sure that these new clean energy jobs are paying family-sustaining wages, with good benefits and union membership," DOE Secretary Jennifer Granholm said during a virtual report release.
As reported by Reuters:
The U.S. energy workforce, from fossil fuels to solar power, shed 840,000 jobs in 2020 as the global health crisis sapped demand for transportation fuels and slowed new projects, according to the annual U.S. Energy Employment Report.
The largest declines were in petroleum and natural gas fuels with a combined loss of 186,000 jobs, or 21% of their workforce, according to the report. Employment in the wind energy industry was among the only sectors to grow, rising a modest 1.8%.
The Biden administration is pushing several initiatives to boost clean energy industries as part of a sweeping infrastructure package being hashed out by Congress, arguing that a transition away from fossil fuels can create millions of good-paying union jobs while countering climate change.
For a deeper dive:
- Renewables were the world's cheapest energy source in 2020 ... ›
- UN Leader Calls for Green Coronavirus Recovery on Earth Day ... ›
- BP to Cut 10,000 Jobs as Oil Demand Plummets - EcoWatch ›
The Bootleg Fire has now burned more than 300,000 acres in southern Oregon and continues to grow as more than 80 large wildfires in the West forced evacuations across the region.
The Bootleg Fire, currently the nation's largest fire, is fueled by extremely dry vegetation and low humidity and grew at an average rate of about one football field every five seconds over its first 10 days. It was just 25% contained as of Sunday night PDT.
As reported by CNN:
Hot temperatures have been making the blaze harder to tackle. "Weather's really against us. It's going to be hot, it's going to be dry and air's going to be unstable which helps the heat raise faster, which brings in more air. All things that are negative for firefighters and positive for fire. So it's going to be a real battle today," Operations Section Chief John Flannigan said during his Sunday morning briefing.
Fire spokesperson Katy O'Hara told CNN that weather conditions need to change in order for the fire to be extinguished.
"We are experiencing extremely dry conditions with record to near record temperatures. Conditions on the ground due in part to the historic drought have accelerated the fire season. The combination of the weather and fuel conditions have led to rapid growth of the fire," O'Hara said. "The scope and scale of the Bootleg Fire will require a season-ending weather event such as a significant storm that is either widespread wetting rain or snow, which in southern Oregon typically occurs in the late fall," she said.
For a deeper dive:
- Records Break and Fires Rage as U.S. West Sees Third Heat Wave ... ›
- Flooded NYC Subways Exemplify Why Climate Is Key to ... ›
More than 100 people are dead and about 1,300 still missing in the wake of extreme rain and flooding western Europe. The torrential rainfall — as much as two months' worth in two days, amounts not seen in the summer for at least a century — unleashed flooding that stacked cars like children's toys and drowned residents in their cellars.
Electricity was also cut off for 165,000 in western Germany. Extreme precipitation is one of the clearest and most widespread impacts of climate change. Warmer air holds more water, and thus dumps more water when it rains — just as a bigger bucket can hold and dump more water.
"Entire villages are flooded," Malu Dreyer, the premier of Germany's Rhineland-Palatinate state, said in a speech to the local parliament. "Houses float away just like that." The flooding is one in a recent series of events — including heatwaves in the Arctic and Western U.S. — shocking climate scientists who say the climate impacts they have long predicted are coming sooner, and across a greater area than they expected.
"I am surprised by how far [the rainfall] is above the previous record," Dieter Gerten, who grew up in a village in the affected area and is now professor of global change climatology and hydrology at the Potsdam Institute for Climate Impact Research, told The Guardian. "We seem to be not just above normal but in domains we didn't expect in terms of spatial extent and the speed it developed."
For a deeper dive:
Flooding: The Guardian, AP, The Washington Post, The New York Times, France24, AFP, NBC, Wall Street Journal, NPR; Rain intensity: Axios; Power outages: Bloomberg; Climate scientists: The Guardian, CNN; Photos: Politico EU; Climate Signals background: Extreme precipitation
- How Global Warming Can Cause Europe's Harsh Winter Weather ... ›
- Europe's Recent Droughts 'Unprecedented' in Millennia, Study Finds ... ›