Incorporating energy efficiency measures can reduce the amount of storage needed to power the nation’s buildings entirely with renewable energy, according to analysis conducted by researchers at the U.S. Department of Energy’s (DOE’s) National Renewable Energy Laboratory (NREL).
As more communities plan to eventually rely on 100% renewable energy, the researchers offer a strategy that could guide their paths — one that shifts away from long-duration storage.
“Minimizing long-duration storage is a key element in trying to achieve the target cost-effectively,” said Sammy Houssainy, co-author with William Livingood of a new paper that outlines an approach to 100% renewables. The research paper, “Optimal Strategies for a Cost-Effective and Reliable 100% Renewable Electrical Grid,” appears in the Journal of Renewable and Sustainable Energy.
The researchers considered solar and wind as the source of renewable energy, given that most plans for meeting the 100% target take those into account. They also used the Department of Energy’s EnergyPlus and OpenStudio building energy modeling tools to simulate energy demand, considering such factors as building size, age, and occupancy type. Data from the U.S. Energy Information Administration informed the scientists about the existing building stock characteristics and energy load used by the buildings.
Further, the researchers separated the country into five climate zones, ranging from the hot and humid (Tampa, Florida) to the very cold (International Falls, Minnesota). The other zones encompassed the cities of New York, El Paso, and Denver. Knowing the extremes of heating and cooling demands in each zone enabled the researchers to select the appropriate mix of renewable power sources to minimize any needed storage.
While varying definitions exist in the literature, for purposes of this study the researchers define long-duration storage as energy storage systems that meet electricity demands for more than 48-hour durations. Therefore, long-duration energy storage provides power days or months after the electricity is generated. However, most long-duration storage technologies are either immature or not available everywhere. The two NREL researchers calculated reaching the last 75% to 100% of renewable energy would result in significant increases in costs associated with long-duration energy storage. Instead of focusing on storage, the researchers emphasized the optimal mix of renewable resources, oversized generation capacities, and investments in energy efficiency. The researchers note that multiple pathways exist to reach 100% renewable and, as the costs and performance of technologies change, new pathways will emerge, but they identified a key pathway that is achievable today.
They also determined that oversizing renewable capacities by a factor of 1.4 to 3.2 and aiming for 52% to 68% in energy savings through building energy-efficiency measures lead to cost-optimal paths depending on region of the country. Houssainy said making homes and offices more energy efficient reduces the amounts of renewable resources needed, decreases the amount of storage, and cuts transmission costs, ultimately supporting the implementation of a carbon-free energy system.
“What’s included in the paper is really a multistep process to follow,” Livingood said. “That process is applicable to large cities, as well small cities. Now, the end result will change, city to city, as this multistep process is followed to cost-optimally achieve the target.”
For example, Tampa would generate all of its electricity from solar panels, while International Falls would receive 100% from wind turbines, the researchers calculated, in order to have the least reliance on storage.
“It is not intended to replace the need for site-specific, detailed engineering design and planning processes for buildings, electric grid, and energy infrastructure,” Livingood said, “but we believe that our novel calculation methodology yields overarching concepts and conclusions that are broadly relevant and applicable. For cost-effectively achieving 100% renewable scenarios, our newly developed calculation methodology provides general principles that help guide these detailed engineering design and planning processes.”
DOE’s Building Technologies Office funded the research, under the advisement of Andrew Burr (formerly DOE).
NREL is the U.S. Department of Energy’s primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for DOE by the Alliance for Sustainable Energy LLC.
Electric bikes are booming in popularity across the US, and cities are starting to take notice. From famous programs like those in Denver to smaller initiatives around the country, local governments are rolling out rebate and incentive programs to make e-bikes more affordable, especially for lower-income residents. The goal? Get more people out of cars and onto two wheels.
E-bike incentives vary widely by city and state, but the overall trend is clear: public officials increasingly see e-bikes as a low-cost, low-emission transportation solution that checks a lot of boxes. E-bikes are cheaper than cars, don’t require gas, and are far more accessible than public transit in many neighborhoods. And with the ability to flatten hills and shrink long commutes, they’re attracting a much broader audience than traditional bikes.
Programs like Denver’s wildly popular e-bike rebate initiative have shown how effective these incentives can be. The city offers over $1,00 off an e-bike purchase depending on income level, and the demand has been enormous. Rhode Island recently launched its own statewide rebate program offering up to $750, and cities like Ann Arbor, Oakland, Providence, and dozens of others are following suit with their own variations. A Bend, Oregon program will offer free e-bikes to locals. Washington D.C. is piloting a rebate targeted at delivery workers, and even some utility companies, like Vermont’s Green Mountain Power, have gotten in on the action.
These programs especially benefit lower-income residents, who may rely on expensive or unreliable transportation options to get to work, school, or the grocery store. By offering higher rebates to income-qualified applicants, many programs aim to level the playing field and make car-free living more realistic.
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Of course, not every program has gone smoothly. California’s statewide e-bike incentive, much hyped before its launch, faced repeated delays and technical issues that left many applicants frustrated. While the program finally began distributing vouchers this year, the rollout highlights the challenges of scaling these efforts statewide without sufficient infrastructure or planning.
Still, the momentum is undeniable. As cities grapple with climate goals, traffic congestion, and rising transportation costs, e-bike rebates are a relatively cheap way to make a big impact. The biggest challenge now may be keeping up with demand.
Electrek’s Take:
This is one of those rare win-win policies: cleaner air, less traffic, more mobility for people who need it most – and it’s all powered by a single horsepower and some political will. Let’s hope even more cities plug into this trend.
Of course, funding is the biggest obstacle to keeping programs like these rolling. But with the benefits stacking up, from reduced road damage to improved air quality, hopefully the rewards outweigh the upfront cost.
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Tesla will use Samsung for as a supplier for its self-driving computer’s next-gen hardware in a $16.5 billion deal, according to Tesla CEO Elon Musk.
But despite planning two generations ahead, the company still doesn’t have a solution to bring the promised full autonomy to hardware that it’s been promising that capability to since 2016.
Earlier today, Samsung announced a 22.8 trillion won ($16.5 billion) deal that would run through 2033. In that filing, Samsung did not name the customer, only that it is a “large global company”. Later, Bloomberg reported that the customer is Tesla, and Musk confirmed this on twitter. Then in his usual bravado, he stated that the deal is “likely much more than that.”
Samsung makes the chips for the self-driving computers in Tesla’s current vehicles, but the next generation will be made by TSMC, first in Taiwan and then later in Arizona. Then the next-next generation will be covered by this new Samsung deal.
The new deal is significant due to TSMC’s global dominance of chipmaking. Samsung has had significant unused capacity, so the Tesla deal is a big boost for the company’s chip foundry business.
Tesla has gone through several generations of chips, previous referred to as “HW,” standing for “hardware,” with a number indicating their generation. More recently, Tesla started referring to its chips with “AI” instead of “HW,” in order to incorporate the tech buzzword du jour.
Currently Tesla is on HW4/AI4, and TSMC will make HW5, then Samsung will make HW6 again.
These generations of hardware each get successively more capable, and can handle more data and thus theoretically become better at self-driving tasks.
Current Tesla HW4 vehicles cannot drive themselves, and are only capable of SAE level 2 operation, which requires an attentive driver behind the steering wheel (though Tesla’s solution does work better than most others). Tesla’s ‘Robotaxi’ system is currently operating in Austin without anyone in the driver’s seat, but has a “safety rider” who can take control of the vehicle, blurring the line somewhat on which SAE level it is operating at.
But what about HW3?
There’s a problem with the differentiation between these generations of hardware: ever since 2016, when Tesla was on version 2 of its hardware, it has promised full self-driving capability on all of its vehicles.
Tesla stated, at the time, that every single Tesla vehicle produced after that date had the hardware that would allow for full self-driving.
It eventually became apparent that HW2 would not be capable of full self-driving tasks, and Tesla upgraded to HW3, promising all HW2 customers that they would get a free upgrade to HW3 if they bought Tesla’s Full Self-Driving system, which has varied in price over time but once cost $15,000.
Now, with the change from HW3 to HW4, we’re seeing indications of a similar run-around.
We’ve already seen differing FSD software versions based on which hardware level vehicles have, with HW3 vehicles getting updates later than HW4 vehicles do. On last week’s Q2 earnings call, Tesla CFO Vaibhav Taneja said:
What we want to do is get unsupervised done on hardware four first. Once it’s done, then we’ll go back and look at what we need to do with the hardware three cars. Like I said, the focus is first to get unsupervised out and then we’ll go back and see what more work we need to do.
“Unsupervised” is Tesla’s new name for actual full self-driving, which would allow a vehicle to drive without the supervision of someone in the driver’s seat. This as opposed to “supervised FSD,” a phrase Tesla started using after about a decade of promising full self-driving without delivering it.
Here, Taneja said that HW3 cars will eventually get FSD, but Tesla hasn’t really figured out the path to that, and it’s focusing on new cars first, then will go back around to see what needs to happen.
Previously, Musk had stated that Tesla “will have to upgrade people’s hardware 3 computer,” but more recently it has become apparent that Tesla really doesn’t have a plan for that upgrade. And Taneja’s comments suggest that Tesla will still try to wedge FSD onto HW3, despite previously admitting that the system is not capable of it.
The existence of future HW5 and even HW6 chips also suggest that current systems are not capable of full self-driving. If HW4 is FSD-capable, then why would Tesla need two more generations of chip in the next two years in order to do the tasks that it promised all of its cars could do a full decade prior?
So, much more than having no solution for HW3 cars (or even HW2 cars, some of which have gotten free upgrades, but others who have been charged $1,000 to upgrade to a computer they already paid for), does this mean that Tesla is going to kick the can further down the road, and eventually have no solution for HW4 and HW5 either?
And, when will we know about these solutions? Tesla has sold millions of vehicles with the promise of self-driving which will seemingly need an upgrade at some point. And many of those vehicles are old enough, at this point, to be retired, despite spending up to $15,000 on a piece of software that has never been delivered to them.
An HW6/AI6 computer will surely have all sorts of new whizbang capabilities, but we were promised those capabilities years ago, and they’re still not delivered yet.
The 30% federal solar tax credit is ending this year. If you’ve ever considered going solar, now’s the time to act. To make sure you find a trusted, reliable solar installer near you that offers competitive pricing, check out EnergySage, a free service that makes it easy for you to go solar. It has hundreds of pre-vetted solar installers competing for your business, ensuring you get high-quality solutions and save 20-30% compared to going it alone. Plus, it’s free to use, and you won’t get sales calls until you select an installer and share your phone number with them.
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Mark Kay’s iconic Pink Cadillac awards are driving into the future for 2025. The company’s first-ever electric Pink Cadillac OPTIQ made its debut during the Mary Kay annual Seminar in Charlotte this weekend, symbolizing a “recharged vision” for the future of the popular brand.
Pioneers in monetizing friendships female empowerment and entrepreneurship, the Pink Cadillac is considered one the most coveted symbols of achievement for Mary Kay sales reps, signifying not just great sales (GM Authorityreported that it took ~$102,000 in annual sales to qualify back in 2001), but also leadership, a history of mentoring others, and a sustained reputation of excellence among their peers.
The women you see behind the wheel of the Pink Cadillac are the real deal, in other words, and the big Caddy really does mean something to people in the know.
The iconic pink Cadillac was born in 1968 when Mary Kay Ash purchased a Cadillac Coupe De Ville from a Dallas dealership and promptly had it painted to match the pale pink Mary Kay lip and eye palette. General Motors later named the color Mary Kay Pink Pearl, and the shade is exclusive to Mary Kay.
“For decades, the Mary Kay pink Cadillac has symbolized accomplishment, aspiration, and the power of recognition,” said Ryan Rogers, Chief Executive Officer of Mary Kay. “With the introduction of the all-electric OPTIQ, we’re honoring that iconic legacy while driving into a transformative future—one grounded in our commitment to sustainability and dedication to inspiring and celebrating the achievements of our independent sales force for generations to come.”
Mary Kay announced its new Pink Cadillac with this video, below.
Same Legacy, New Energy
“The legacy continues with the new, all-electric (and still very pink) Cadillac Otiq [sic],” reads the official Mary Kay copy on YouTube. “The Optiq remains instantly recognizable with the pink pearl exterior, while modernizing with sleek, cutting-edge features. In addition, this vehicle showcases our commitment and dedication to sustainability by reducing our carbon footprint while continuing to inspire.”
Speaking of inspiration, I can’t hardly hear the words “Pink Cadillac” without thinking of the song. But, since “Bruce Springsteen” has become something of a trigger word for the MAGA snowflakes in the audience, I’ll post a different, but similarly great song about rose-tinted GM flagships from Dope Lemon. You can let me know what you think of it in the comments.
As ever, the Cadillac is not a “gift,” per se – but typically takes the form of a two year lease paid for by Mary Kay. No word yet on what the exact shape and form the OPTIQ deal will take.
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