houses

Trends in rooftop solar

October 8, 2024 By EarthWise Leave a Comment

Rooftop solar power in the United States has increased by a factor of ten over the past decade and the majority of that growth has been in the past six or seven years. At this point, about 7% of American homes have solar panels on their roofs – about 5 million in total.

Rooftop solar really began experiencing widespread use about 20 years ago. Over that time period, the amount of electricity that panels are able to produce has grown substantially and the cost of solar power systems has dropped dramatically.

Twenty years ago, the median sized residential solar system generated 2.4 kilowatts of power. In 2023, the median size was 7.4 kilowatts. Roofs haven’t gotten bigger; solar panels have gotten better.

More importantly, 20 years ago, the average cost of installing solar power was $12 a watt. In 2023, the cost was $4.20 a watt.

Americans in fact pay considerably more for solar power than citizens in many other countries. The reason is not the price of the equipment; it is so-called soft costs. These include labor, financing, and permitting. Driving down soft costs is complicated and difficult. For one thing, it is important for solar industry jobs to have high pay and good benefits.

The cost of solar also varies significantly by state. California is the leading state for solar power and its median solar cost is the $4.20 a watt, the same as the national average. Nevada has the lowest cost at $3.40 a watt and Utah has the highest at $5.20 a watt.

**********

Web Links

Bigger and Less Expensive: A Snapshot of U.S. Rooftop Solar Power and How It’s Changed

Photo, posted September 18, 2011, courtesy of Team Massachusetts 4D Home via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fungus And Carbon Storage | Earth Wise

July 26, 2023 By EarthWise Leave a Comment

It is well-known that plants and trees store enormous amounts of carbon. What has not been common knowledge is that the vast underground network of fungi across the world’s lands stores billions of tons carbon, roughly equivalent to 36% of yearly global fossil fuel emissions.

These mycorrhizal fungi form symbiotic relationships with almost all land plants. The fungi transport carbon, converted by sugars and fats by plants, into soil. They have been supporting life on land for at least 450 million years and form sprawling underground networks everywhere – even beneath roads, gardens, and houses – on every continent on earth.

An international team of scientists analyzed hundreds of studies looking at plant-soil processes to understand how much carbon is being stored by fungi on a global scale. The findings, published in the journal Current Biology, revealed that over 13 billion tons of CO2 is transferred from plants to fungi each year, more than China emits annually. This process transforms the soil beneath our feet to a massive carbon pool and constitutes the most effective carbon storage activity in the world.

Given that fungi have such a crucial role in mitigating carbon emissions, the researchers are recommending that fungi should be considered in biodiversity and conservation policies. More needs to be done in protecting the underground networks of mycorrhizal fungi. The UN has warned that human activities are degrading soils and that 90% of the world’s soils could be degraded by 2050. Not only would this obviously be very bad for the productivity of crops and plants, but we now know this could be catastrophic for curbing climate change and rising temperatures.

**********

Web Links

Fungi stores a third of carbon from fossil fuel emissions and could be essential to reaching net zero

Photo, posted May 28, 2023, courtesy of Geoff McKay via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Electric Cars And Apartments | Earth Wise

July 10, 2023 By EarthWise Leave a Comment

The transition to electric cars is underway. People are increasingly buying them, carmakers are switching over to making them, and governments are providing incentives as well as legislating the changeover. More and more consumers want to lower their carbon footprints and stop burning fossil fuels. But one very large group of consumers faces an uphill battle in switching to electric cars: people who rent their dwellings.

About one third of our country lives in rented apartments or houses. These nearly 110 million Americans are more likely to be in the bottom half of income and net worth and are more likely to be people of color. These people are less likely to have the spare cash to make upgrades to their property such as car chargers and may not be able to get permission from their landlords to do it anyway.

Renters face what is known as the “split-incentive problem” or the “landlord-tenant problem.” Three-quarters of tenants in the US pay their own utility bills, so they have a strong incentive to conserve electricity, water, and gas. Their landlords, on the other hand, have little incentive to upgrade appliances and systems to be more environmentally responsible. Studies have shown that on average renters use 3% more energy than homeowners for this reason.

There are some landlords who are being proactive and installing facilities for charging cars on their properties. This will undoubtedly become an increasingly sought-after feature for renters. But in the meantime, millions of them have a more difficult time driving electric cars. They can charge at public chargers or perhaps at work. But at the moment, homeowners are three times more likely than renters to own an electric car.

**********

Web Links

The coming battle between Americans who want to go electric and their landlords

Photo, posted July 22, 2022, courtesy of Chris Yarzab via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Carbon Storage In Harvested Wood | Earth Wise

September 26, 2022 By EarthWise Leave a Comment

Trees are an exceedingly important carbon sink on our planet. For this reason, deforestation is a major contributor to climate change. But when trees are harvested for wood products like lumber, much of the carbon in that wood continues to be stored. Even when a wood product is discarded at the end of its useful life, it can keep storing carbon.

Over 90% of new single-family homes in the U.S. are built with wood. Each year, about 400,000 homes, apartment buildings, and other housing units are lost to floods and other natural disasters. Others fall apart from decay or are torn down to be replaced with newer structures. Given how much carbon is stored in houses, it is important to understand what the future trajectory of residential structures will be.

A new study by the USDA Forest Service published in the journal PLOS ONE looks at the future of harvested wood products in residential structures. According to the study, wood products in these structures will continue to increase the country’s carbon storage for the next 50 years.

Even after residential structures reach the end of their useful life and much of the materials end up in landfills (which is typical in this country), the wood products do not immediately release their carbon. It may take decades for that to happen.

The study looked at various scenarios for future home construction. Although housing starts are projected to decline in the future, residential housing and the need to maintain existing structures are projected to continue to increase carbon storage in wood products for the next several decades.

The role of trees as a carbon sink does not end when they are harvested for their wood.

**********

Web Links

Carbon Storage in Harvested Wood Products

Photo, posted January 27, 2022, courtesy of Luke McKernan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Floating Homes In The Netherlands | Earth Wise

January 24, 2022 By EarthWise Leave a Comment

The Netherlands is a country that is largely built on reclaimed land and a third of it remains below sea level. The Dutch have long experience with dealing with rising waters. The city of Amsterdam has almost 3,000 houseboats in its canals.

As sea levels continue to rise across the globe, it is no surprise that the Dutch have taken the lead in creating communities composed of floating houses and buildings.

A floating house is a structure fixed to the shore, often resting on steel poles, and usually connected to the local sewer system and power grid. They are much like ordinary houses except that instead of a basement, they have a concrete hull that acts as a counterweight, allowing them to remain stable in the water.

The ones in the Netherlands are often prefabricated, square-shaped, three-story townhouses. Rotterdam, which is 90% below sea level, is home to the world’s largest floating office building as well as a floating farm.

Floating buildings have their challenges, not the least of which are the effects of severe wind and rainstorms, or even the passing of large ships which can make the buildings rock. Infrastructure like electricity and sewer service is not that simple to implement for the buildings. But the benefits of floating buildings may outweigh the costs.

For cities facing worsening floods and a shortage of buildable land, floating homes are a potential solution for expanding urban housing in the age of climate change. Dutch engineers are spearheading floating building projects in Britain, France, and Norway, as well as in threatened island locations like French Polynesia and the Maldives.

**********

Web Links

Embracing a Wetter Future, the Dutch Turn to Floating Homes

Photo, posted May 23, 2007, courtesy of Jeff Hutchison via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Street Trees And Depression | Earth Wise

February 25, 2021 By EarthWise Leave a Comment

**According to a study published in the journal Jama Network Open last fall, the COVID-19 pandemic has tripled the rate of depression in U.S. adults in all demographic groups.**

Previous studies have demonstrated that greenspaces in urban areas can have a positive effect on those people experiencing mental ill health. But most of those studies used self-reporting measures, which makes it difficult to compare results and draw conclusions.

As a result, an interdisciplinary research team from three research organizations in Germany tried to improve upon the work by involving an objective indicator: prescriptions of antidepressants. To figure out whether greenspaces – in this case street trees – could positively influence mental health, the researchers focused on how the number of street trees and their proximity to homes correlated to the number of prescribed antidepressants.

After analyzing data from nearly 10,000 people living in Leipzig, Germany, and combining the findings with data on city street trees, researchers were able to identify an association between antidepressant prescriptions and the number of street trees. The results were controlled for other factors known to be associated with depression, such as employment, gender, age, and body weight.

Having more trees within 100 meters of the home was associated with a reduced risk of being prescribed antidepressants. The association was especially strong for groups of people deprived of street trees.

Street trees in urban cities can not only serve as a nature-based solution for good mental health, but they can also contribute to climate change mitigation and biodiversity conservation.

**********

Web Links

Street trees close to the home may reduce the risk of depression

Photo, posted August 17, 2011, courtesy of Aleksandr Zykov via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Building For Climate Change

May 13, 2019 By EarthWise Leave a Comment

The manifestations of climate change are creating increasingly familiar images: floodwaters rising up house windows, charred buildings in the wake of wildfires, and homes and businesses demolished by storm winds. As these sorts of calamities become ever more common, changes to how houses are built are going to be necessary.

How can homes become more resilient against severe and unpredictable weather?

Research at Carlton University’s Sprott School of Business looks at this issue.

As an example, houses can be framed and finished in certain ways that help protect them from wind and flooding. But such methods are currently only happening in the custom-build fringes of the housing sector. Widespread adoption will require, at the minimum, significant changes to building codes.

Revising building codes is not an easy matter. The codes themselves are highly technical and complex, and beyond that, the process Is often politicized.

Even simple things like hurricane ties, which are small pieces of hardware that prevent a roof from lifting during a severe wind are not now included in building codes. Insurance companies support their use as inexpensive protection for houses. But even though the overall cost is relatively minor, the building industry pushes back at the additional expense.

The need to reduce carbon emissions has created a push for sustainable housing. But the increasingly erratic weather means that houses also need resilience and adaptation. These features will inevitably add costs and incorporating them into building codes requires producing convincing business cases.

The U.S. experienced 394 natural catastrophe events last year costing $225 billion in damage. Finding ways to make homes and businesses more resilient is not just a good idea; it is essential.

**********