Fighting Climate Change with Heat Pumps

Geez, it’s hot. We’ve been sweltering through record-high temperatures here in California. Our house is one of the 30% of California homes without air conditioning. And our furnace is getting older. If we replaced our furnace with a heat pump, we could get efficient heating and efficient cooling all in one. And we’d be doing our part to move the decarbonization-via-building-electrification ball forward. So we’re getting heat pump curious.

Joe Biden is excited about heat pumps. He recently invoked the Defense Production Act to ramp up domestic production, and the Inflation Reduction Act includes generous heat pump tax credits and rebates. Governor Gavin is also heat-pumped. He’s offering rebates to California households that will help him meet his target of 6 million new residential heat pumps by 2030.

Some recent research out of UC Davis finds that, for households that are installing AC for the first time, or households that need to replace their old air conditioner with a new unit, it makes climate sense to make the AC a heat pump and replace the furnace. We’re pretty convinced we have a heat pump in our future. For us, the question is not whether to heat pump…but when?

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UC Davis Developing Tech Using Current Air Conditioning Systems to Combat Climate Change Effects

DAVIS, Calif. (KGO) — The Western Cooling Efficiency Center at UC Davis is trying to develop new air technology that addresses problems with the grid and the challenges of climate change using our current AC systems.

This research would address the problem of energy consumption in peak periods on hot days.

“The grid is stressed late afternoon and what occurs is that there’s too much demand for electricity. One way to address that is to use a battery. This new technology instead of using a battery uses a liquid that absorbs moisture and by using this liquid that absorbs moisture it acts like a battery but is much less expensive that a battery for doing the same thing,” said Mark Modera, the former Director of the Cooling Efficiency Center.

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Heat pumps: Coming to a home near you?

Karl Johnson was just looking for a way to keep his Corbin Park home, built in the early 20th century, comfortable.

The gas-fed furnace was on its way out, and his central air conditioner had already failed. To cool the home, Johnson had several portable units running throughout the day in the summer, belching hot air back into the rooms and driving up his energy bill each month.

“At some point, it’s just insanity to keep up with trying to address the issue,” Johnson said.

So he started researching central air systems online and settled on a heat pump for his home – a combination heating and cooling, electrified system that policymakers and the White House have been pushing as a method to reduce greenhouse gas emissions.

Democrats’ Inflation Reduction Act, which passed the Senate by a razor-thin 51-50 vote on Sunday, includes a major boost for climate-friendly energy systems, including heat pumps. 

The bill includes rebates and incentives for the purchase of heat pumps for both air and water conditioning in residential structures. The legislation would provide rebates of up to $8,000 to install heat pumps in homes for the next decade, according to Bloomberg. Those who wouldn’t qualify for the rebate could still get tax credits of up to $2,000.

The inflation act also piggybacks on a decision made by President Joe Biden in June to use the Defense Production Act to spur domestic production of appliances that help curb carbon emissions, including heat pumps, by providing $500 million in that effort, according to The Hill.

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Do DIY air filters work against California wildfire smoke? What to know about cost and safety

Do-it-yourself air filters are safe, effective and can be used to protect your lungs from California wildfire smoke.

Wildfire smoke is harmful and can stretch hundreds of miles. The smoke from the 2021 Dixie Fire in California was felt as far as Denver, The New York Times reported. Here are two safe options, according to the University of California, Davis, the U.S. Environmental Protection Agency and the California Air Resources Board.

WHEN SHOULD I USE AN AIR FILTER?
Good air filters can remove dangerous smoke particles from your home. According to the California Air Resources Board, indoor air cleaners help filter out small particulate matter that can cause health concerns.

Wildfire smoke produces harmful air pollutants that can aggravate existing health problems and increase the risk of heart attack or stroke.

The resource board recommends using a certified air cleaner whenever the air quality index is at an unhealthy level, which you can check at AirNow.gov. The agency also says if a board-certified commercial system is not an option for your home, a DIY is an OK alternative.

“These temporary air cleaners should be used with extreme caution, and only if other air cleaning options are unavailable,” the board writes on its website. It says never leave the device unattended and only use box fans manufactured in the last 10 years (after 2012), as those fans “will have a fused plug, which will prevent electrical fires if the device is knocked over.”

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close up of an EV being charged

Ask a Scientist: In Search of a ‘Green’ Electric Car Battery

Lithium-ion batteries are the most popular battery in use today. First commercialized in 1991, their cost has declined by a remarkable 97 percent over the last three decades, enabling the rapid growth of mobile phones, laptops and more recently, electric cars. Global demand for the batteries is projected to increase dramatically by the end of this decade, largely due to the growing adoption of electric vehicles (EVs) around the world.

More EVs is good news for the climate. After all, as a 2020 Union of Concerned Scientists (UCS) analysis shows—and an updated, soon-to-be-released analysis will confirm—EVs’ lifecycle global warming emissions are dramatically lower than that of gas- and diesel-powered vehicles. But mining the materials used in EV batteries, including cobalt, lithium and nickel, comes with its own set of public-health, environmental and human-rights challenges. Despite EVs’ considerable environmental benefits, it will be imperative to “green” the material sourcing process to ensure a more sustainable and ethical supply chain as the world transitions to an electrified transportation system.

Fortunately, scientists are on the case. They are altering battery chemistries to reduce reliance on certain metals, such as cobalt, for example, and coming up with ways to recycle and repurpose batteries to minimize the need for new raw materials altogether.

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Activists fear a new threat to biodiversity—renewable energy

A small Nevada wildflower named Tiehm’s buckwheat might still be living in obscurity if it had not happened to grow in soil full of lithium. As it is, that could prove its downfall.

Lithium is needed to make the high-powered batteries that are helping the world transition to electric vehicles. Demand is soaring, and mining companies are eager to take it out of the ground at several new sites in Nevada, already home to the only existing lithium mine in the U.S.

But Tiehm’s buckwheat is rarer than lithium. It grows only on approximately 10 acres of land at Rhyolite Ridge in southwestern Nevada—right where one of the new lithium mines is planned.

“One guy on a bulldozer could drive it extinct in one afternoon,” says Patrick Donnelly, the Great Basin Director for the Center for Biological Diversity and one of the flower’s biggest advocates. 

He and some other conservationists see the flower and the mine as emblematic of a broad and disturbing trend: There is a growing conflict, they say, between efforts to address two environmental crises—a rapidly warming climate on the one hand, and a staggering rise in extinction on the other. 

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A District Energy System Design Could Cut More Emissions for Proposed Davis Innovation Sustainability Campus

Homes and businesses use over 25 percent of California’s energy. With a number of different space heating and cooling technologies available to developers, it is important to understand and quantify potential greenhouse gas (GHG) impacts.

A study, completed by the UC Davis Western Cooling Efficiency Center (WCEC), analyzed the GHG emissions for two different heating and cooling options for a proposed development in Davis – the Davis Innovation Sustainability Campus (DiSC). Researchers analyzed GHG emissions for: 1) the proposed all-electric, high-efficiency design, which would use packaged heat pump equipment for heating and cooling the buildings and 2) a potential upgrade to an all-electric, very high efficiency design, which would use a district energy system. A district energy system uses a central plant heat pump and chiller to heat and cool water that is piped to buildings for heating and cooling. 

“Based on predicted energy consumption data provided by Trane, we found that a district energy system could further improve energy efficiency by 26%, reduce total energy consumption by 14%, and reduce GHG emissions by 16% over the already highly efficient proposed design,” said lead researcher David Vernon, Co-Director of Engineering for the UC Davis Western Cooling Efficiency Center.

DiSC energy system options

DiSC is a proposed development that would build new residential, office, laboratory, and manufacturing buildings on the eastern edge of Davis. The developer team is required by the Davis City Council to build an all-electric design with an energy efficiency level 30% more efficient than required by Title 24 building codes.

“The developer funded us to look at a district energy system design with large thermal energy storage because it has the potential to greatly reduce GHG emissions,” Vernon said. “It can help stabilize the grid by using energy when renewable generation is high and reducing energy consumption when renewable generation is low.”

To meet California’s climate goals requires large increases in renewable energy generation, energy storage, and load shifting technologies. District energy systems with large thermal energy storage have the potential to be an effective energy storage and load shifting strategy. The WCEC mission is to advance design, monitoring, and objective reporting of the performance of these types of technologies to inform policy and economic decisionmakers.

Energy modeling and analysis

The heating, ventilation, and air conditioning (HVAC) manufacturer Trane completed energy models of the proposed baseline and district energy system designs and provided the hourly energy consumption results. The WCEC researchers then used these hourly energy consumption results to calculate Time Dependent Valuation—a metric that incorporates the social and environmental impacts of energy used to evaluate energy efficiency, total energy consumption, and GHG emissions of the designs.   

“Our analysis shows that district energy systems offer significant opportunities to reduce energy consumption and GHG emissions compared to more common HVAC designs,” said Vernon. “It is important to note that our results are on the conservative side, and implementation of this design could result in even larger GHG savings.”

This study was funded by Ramco Enterprises, Inc. and the Buzz Oates Group of Companies.

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How Eco-Friendly are Electric Vehicles? It All Depends on the Battery

OAKLAND, Calif. (KGO) — By 2035, every passenger vehicle sold in California must be a zero-emission vehicle.

That means it must run on electricity, hydrogen or another alternative fuel that does not generate air pollution to operate.

The mandate is expected to reduce greenhouse gases in the state by about 35%.

But, while zero-emission vehicles are being touted as one solution to our climate crisis, their batteries could also represent an environmental hazard.

Currently, batteries from first-generation hybrid vehicles are starting to make their way to junkyards.

We visited several auto recyclers in the San Francisco area and found hybrid batteries tossed among other car parts or piled up in a corner. One was dangling from the engine compartment of an old Prius that no longer had a hood and had many parts already pulled out.

Operators did not know what to do with them.

“There are risks associated with these aged batteries or damaged batteries. Lithium-ion batteries that we use in electric vehicles are a fire hazard. It’s important to make sure that these batteries are managed correctly at the end of life,” said Alissa Kendal, a professor of Civil and Environmental Engineering at UC Davis.

Kendall said the metals in the batteries are hazardous and could leach into the environment if they are not properly handled.

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female scientist examining water

Leaks an Untapped Opportunity for Water Savings

Before a drop of treated water in California ever reaches a consumer’s faucet, about 8% of it has already been wasted due to leaks in the delivery system. Nationally, the waste is even higher, at 17%. This represents an untapped opportunity for water savings, according to a study from the University of California, Davis. 

The study, published in the journal Environmental Research Letters, is the first large-scale assessment of utility-level water loss in the United States. It found that leak reduction by utilities can be the most cost-effective tool in an urban water manager’s toolkit, provided utility-specific approaches are used. 

“When I first heard about ‘leaks’ I thought it sounded boring, but leaks are a huge component of our water systems and have a larger opportunity than many other water-saving methods to make an impact,” said lead author Amanda Rupiper, a postdoctoral scholar with the UC Davis Center for Water-Energy Efficiency. “As the first state to regulate its water losses, a lot of eyes are watching California, and this is an opportunity to impact policy here and elsewhere.”

Amid a multiyear drought, the passage of Senate Bill 555 in 2015 made California the first in the nation and among the first in the world to require water utilities to regulate their water losses.

Be Specific

Using data from more than 800 utilities across California, Georgia, Tennessee and Texas, the authors characterized water losses across the country. They developed a model to assess the economically efficient level of losses, and used that model to compare various water loss regulations and modeling approaches.

The study found that one-size-fits-all approaches to leak management are not effective, economical or equitable for utilities, which vary in size and resources. Uniform approaches could lead to the mismanagement of urban water losses. However, applying utility-specific performance standards can deliver a similar amount of water savings at a profit for both utilities and society.

“Regulations that impose a uniform standard across all utilities will result in water reductions that are too stringent in some cases, too relaxed in others, and too costly overall,” the paper concludes.

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Egret standing on solar panels

Floating Solar Panels Could Be the Next Big Thing in Clean Energy

Solar panels can be placed on your roof, on a plot of land, or basically anywhere else where they  are anchored to something solid. That said, there are only so many solid spaces available to install them. To beat climate change, our electricity mix is going to need a lot more renewable energy systems to take over fossil fuels.  Many in the solar industry are looking for a new home for solar panels—possibly even floating on water.

Floating solar farms have been around for over a decade, but water-bound panels became much more prominent in the last few years. The basic idea is to attach solar panels to plastic floats which then drift on a body of water. These floating solar arrays are typically placed on man-made bodies of water—a town’s water reservoir, an irrigation reservoir, a water treatment facility—as to avoid interfering with plant and animal species that live in natural bodies of water. For instance, the United States’ largest floating solar farm sits on a wastewater pond in California and has a nearly five megawatt capacity.

The floating solar industry is expected to grow dramatically over the next decade, but only about two percent of this year’s new solar installations are water-bound.  

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