Joe DeCarolis
@jfdecarolis.bsky.social
Focused on applying state-of-the-art data systems, models, and analysis to inform decision making on energy. Professor at NC State University; served as the 10th Administrator of the U.S. Energy Information Administration. Personal account.
Pinned
DeCarolis named head of Engineering and Public Policy
Joseph DeCarolis has been named head of the Department of Engineering and Public Policy.
engineering.cmu.edu
Some personal news: This November, I'll be returning to Carnegie Mellon (@cmu.edu) as head of the Department of Engineering and Public Policy (EPP).
I'm honored and excited to help lead EPP into its next chapter.
engineering.cmu.edu/news-events/...
I'm honored and excited to help lead EPP into its next chapter.
engineering.cmu.edu/news-events/...
Funny story about George Dantzig's formulation of the canonical diet program to test his newly developed simplex algorithm. The lesson? Embed some common sense in the model formulation.
Thanks to @bistline.bsky.social for sharing.
Thanks to @bistline.bsky.social for sharing.
Modeling Monday: In honor of George Dantzig's 111th birthday, everyone knows the "late to class/solves two open problems thinking they were homework" story. Fewer know the hilarious backstory of the diet problem. Buckle up for an operations research thread... 🧵
November 13, 2025 at 12:50 PM
Funny story about George Dantzig's formulation of the canonical diet program to test his newly developed simplex algorithm. The lesson? Embed some common sense in the model formulation.
Thanks to @bistline.bsky.social for sharing.
Thanks to @bistline.bsky.social for sharing.
Reposted by Joe DeCarolis
Today we submitted our public comment on critical flaws in EPA's rationale for rescinding its authority to regulate greenhouse gas emissions.
This proposed move is a big deal with profound implications for our future. Today's the last day to comment. www.cmu.edu/cit/veg/publ...
This proposed move is a big deal with profound implications for our future. Today's the last day to comment. www.cmu.edu/cit/veg/publ...
September 22, 2025 at 8:42 PM
Today we submitted our public comment on critical flaws in EPA's rationale for rescinding its authority to regulate greenhouse gas emissions.
This proposed move is a big deal with profound implications for our future. Today's the last day to comment. www.cmu.edu/cit/veg/publ...
This proposed move is a big deal with profound implications for our future. Today's the last day to comment. www.cmu.edu/cit/veg/publ...
Excellent piece by @bencasselman.bsky.social on the BLS data revisions.
The U.S. Energy Information Administration, another federal statistical agency, faces similar data challenges. The accuracy vs timeliness tradeoff is universal: data collected at higher frequency is inherently noisier.
The U.S. Energy Information Administration, another federal statistical agency, faces similar data challenges. The accuracy vs timeliness tradeoff is universal: data collected at higher frequency is inherently noisier.
Data revisions are a normal, necessary part of trying to measure a $30 trillion economy in real time. They can also be jarring, especially for people who don't obsessively scrutinize every jobs report.
So I dug into the how and why of revisions. A few big takeaways:
#EconSky
So I dug into the how and why of revisions. A few big takeaways:
#EconSky
Why the B.L.S. Regularly Revises Jobs Data
www.nytimes.com
August 7, 2025 at 2:36 AM
Excellent piece by @bencasselman.bsky.social on the BLS data revisions.
The U.S. Energy Information Administration, another federal statistical agency, faces similar data challenges. The accuracy vs timeliness tradeoff is universal: data collected at higher frequency is inherently noisier.
The U.S. Energy Information Administration, another federal statistical agency, faces similar data challenges. The accuracy vs timeliness tradeoff is universal: data collected at higher frequency is inherently noisier.
Reposted by Joe DeCarolis
And here the timely EIA data (and analysis) on oil trade volumes through the Strait of Hormuz - 20% of global oil consumption:
www.eia.gov/todayinenerg...
www.eia.gov/todayinenerg...
June 22, 2025 at 8:29 PM
And here the timely EIA data (and analysis) on oil trade volumes through the Strait of Hormuz - 20% of global oil consumption:
www.eia.gov/todayinenerg...
www.eia.gov/todayinenerg...
I was happy to participate in this event and explain how the U.S. Energy Information Administration meets energy data needs in the United States. 🔌💡
💡 ICYMI: Europe’s energy information problem
Europe suffers from an under-provision of energy information. @nworbmot.bsky.social
@jfdecarolis.bsky.social @bmcwilliams.bsky.social &
@gzachmann.bsky.social discussed possible solutions
🔗Watch the event recording:
Europe suffers from an under-provision of energy information. @nworbmot.bsky.social
@jfdecarolis.bsky.social @bmcwilliams.bsky.social &
@gzachmann.bsky.social discussed possible solutions
🔗Watch the event recording:
Europe’s energy information problem
Is Europe flying blind on energy policy — and how can better data help steer the transition?
buff.ly
May 13, 2025 at 12:33 PM
I was happy to participate in this event and explain how the U.S. Energy Information Administration meets energy data needs in the United States. 🔌💡
Some personal news: This November, I'll be returning to Carnegie Mellon (@cmu.edu) as head of the Department of Engineering and Public Policy (EPP).
I'm honored and excited to help lead EPP into its next chapter.
engineering.cmu.edu/news-events/...
I'm honored and excited to help lead EPP into its next chapter.
engineering.cmu.edu/news-events/...
DeCarolis named head of Engineering and Public Policy
Joseph DeCarolis has been named head of the Department of Engineering and Public Policy.
engineering.cmu.edu
May 6, 2025 at 12:54 PM
Some personal news: This November, I'll be returning to Carnegie Mellon (@cmu.edu) as head of the Department of Engineering and Public Policy (EPP).
I'm honored and excited to help lead EPP into its next chapter.
engineering.cmu.edu/news-events/...
I'm honored and excited to help lead EPP into its next chapter.
engineering.cmu.edu/news-events/...
Reposted by Joe DeCarolis
If you want to lower energy costs for Americans, you must first understand the US energy system. You can't do that without the robust, accurate data the EIA provides.
The Trump Administration's haphazard dismantling of the EIA will hurt our ability to increase access to cheap, reliable energy.
The Trump Administration's haphazard dismantling of the EIA will hurt our ability to increase access to cheap, reliable energy.
Over 100 employees leave US EIA, putting crucial energy data at risk, sources say
The U.S. government's energy statistics arm is set to lose over 100 employees after the Trump administration's latest round of resignation offers, putting at risk some of the most closely watched energy reports globally, three sources told Reuters.
www.reuters.com
April 30, 2025 at 3:48 PM
If you want to lower energy costs for Americans, you must first understand the US energy system. You can't do that without the robust, accurate data the EIA provides.
The Trump Administration's haphazard dismantling of the EIA will hurt our ability to increase access to cheap, reliable energy.
The Trump Administration's haphazard dismantling of the EIA will hurt our ability to increase access to cheap, reliable energy.
EIA’s Annual Energy Outlook 2025 (AEO2025) was published this week: www.eia.gov/outlooks/aeo/
I’ve taken some time with the published data, and want to share some high-level insights from my personal perspective. 🔌💡
🧵👇
I’ve taken some time with the published data, and want to share some high-level insights from my personal perspective. 🔌💡
🧵👇
Annual Energy Outlook 2025 - U.S. Energy Information Administration (EIA)
www.eia.gov
April 17, 2025 at 6:15 PM
EIA’s Annual Energy Outlook 2025 (AEO2025) was published this week: www.eia.gov/outlooks/aeo/
I’ve taken some time with the published data, and want to share some high-level insights from my personal perspective. 🔌💡
🧵👇
I’ve taken some time with the published data, and want to share some high-level insights from my personal perspective. 🔌💡
🧵👇
🔌💡
A great short update from EIA on grid connected battery capacity. And check out the linked page that is a long read on forms of grid storage and their uses.
www.eia.gov/todayinenerg...
www.eia.gov/energyexplai...
www.eia.gov/todayinenerg...
www.eia.gov/energyexplai...
U.S. battery capacity increased 66% in 2024 - U.S. Energy Information Administration (EIA)
www.eia.gov
March 17, 2025 at 3:41 PM
🔌💡
Meredith Fowlie discusses recent work examining the impacts of ⬆️ U.S. LNG exports.
⬆️ exports will put ⬆️ pressure on domestic prices, but models disagree on the global GHG impacts. Short-term displacement of coal tends to ⬇️ emissions, but longer-term delay in renewable adoption can ⬆️ emissions 🔌💡
⬆️ exports will put ⬆️ pressure on domestic prices, but models disagree on the global GHG impacts. Short-term displacement of coal tends to ⬇️ emissions, but longer-term delay in renewable adoption can ⬆️ emissions 🔌💡
New Energy Institute Blog Post: It’s Game on for Liquefied Natural Gas (LNG) Exports - Meredith Fowlie
#naturalgas #fossilfuels #greenhousegasemissions #coal #renewableenergy
energyathaas.wordpress.com/2025/02/24/i...
#naturalgas #fossilfuels #greenhousegasemissions #coal #renewableenergy
energyathaas.wordpress.com/2025/02/24/i...
February 25, 2025 at 7:26 PM
Meredith Fowlie discusses recent work examining the impacts of ⬆️ U.S. LNG exports.
⬆️ exports will put ⬆️ pressure on domestic prices, but models disagree on the global GHG impacts. Short-term displacement of coal tends to ⬇️ emissions, but longer-term delay in renewable adoption can ⬆️ emissions 🔌💡
⬆️ exports will put ⬆️ pressure on domestic prices, but models disagree on the global GHG impacts. Short-term displacement of coal tends to ⬇️ emissions, but longer-term delay in renewable adoption can ⬆️ emissions 🔌💡
Great panel on an important topic...
What's the role of advanced technologies in future energy systems? Join us for a webinar next Thursday, Feb. 13: umich.zoom.us/webinar/regi...
February 6, 2025 at 5:14 PM
Great panel on an important topic...
In the run-up to my Senate confirmation, I was told to sell my 10 shares of Apple stock — 10 shares — to avoid a conflict of interest. Why? Because I could direct my agency's IT dept to purchase Apple products.
Frustrating that the most powerful can flout the rules the rest of us take so seriously.
Frustrating that the most powerful can flout the rules the rest of us take so seriously.
Our deep dive into Musk's takeover: Even some officials who like what Musk is doing feel helpless to hold him accountable. His allies are diving in to agencies, gaining access to systems, planning layoffs, and proposing a sweeping AI initiative to review contracts. www.nytimes.com/2025/02/03/u...
Inside Musk’s Aggressive Incursion Into the Federal Government (Gift Article)
The billionaire is creating major upheaval as his team sweeps through agencies, in what has been an extraordinary flexing of power by a private individual.
www.nytimes.com
February 4, 2025 at 3:19 AM
In the run-up to my Senate confirmation, I was told to sell my 10 shares of Apple stock — 10 shares — to avoid a conflict of interest. Why? Because I could direct my agency's IT dept to purchase Apple products.
Frustrating that the most powerful can flout the rules the rest of us take so seriously.
Frustrating that the most powerful can flout the rules the rest of us take so seriously.
Reposted by Joe DeCarolis
Macro-Energy Systems is now on Bluesky! MES is an emergent field and research community that focuses on large-scale, systems-level, long-term aspects of energy systems and their implications for other systems.
Follow this account for MES community updates, and visit our website for more!
Follow this account for MES community updates, and visit our website for more!
Macro-Energy Systems
www.macroenergysystems.org
January 29, 2025 at 9:16 PM
Macro-Energy Systems is now on Bluesky! MES is an emergent field and research community that focuses on large-scale, systems-level, long-term aspects of energy systems and their implications for other systems.
Follow this account for MES community updates, and visit our website for more!
Follow this account for MES community updates, and visit our website for more!
Reposted by Joe DeCarolis
Calling all Macro Energy Systems enthusiasts. I created this macro energy systems starter pack. Featuring @jessedjenkins.com @gruberte.bsky.social @jfdecarolis.bsky.social @patricia-levi.bsky.social #energySky
Let me know in the comments who I missed and I'll add them.
go.bsky.app/TTnoSNL
Let me know in the comments who I missed and I'll add them.
go.bsky.app/TTnoSNL
December 3, 2024 at 1:54 AM
Calling all Macro Energy Systems enthusiasts. I created this macro energy systems starter pack. Featuring @jessedjenkins.com @gruberte.bsky.social @jfdecarolis.bsky.social @patricia-levi.bsky.social #energySky
Let me know in the comments who I missed and I'll add them.
go.bsky.app/TTnoSNL
Let me know in the comments who I missed and I'll add them.
go.bsky.app/TTnoSNL
I had the honor to deliver the MITei Fall Colloquium this year. My title sums it up: “Stay humble and prepare for surprises: lessons for the energy transition”
The talk features new animations showing past EIA projections versus reality.
Some highlights. 🧵👇 🔌💡
www.youtube.com/watch?v=V0fL...
The talk features new animations showing past EIA projections versus reality.
Some highlights. 🧵👇 🔌💡
www.youtube.com/watch?v=V0fL...
Stay humble and prepare for surprises: Lessons for the energy transition with Joseph F. DeCarolis
YouTube video by MIT Energy Initiative
www.youtube.com
November 25, 2024 at 8:39 PM
I had the honor to deliver the MITei Fall Colloquium this year. My title sums it up: “Stay humble and prepare for surprises: lessons for the energy transition”
The talk features new animations showing past EIA projections versus reality.
Some highlights. 🧵👇 🔌💡
www.youtube.com/watch?v=V0fL...
The talk features new animations showing past EIA projections versus reality.
Some highlights. 🧵👇 🔌💡
www.youtube.com/watch?v=V0fL...
Project BlueSky is an EIA initiative to develop a next generation energy systems model.
Today, as a first step, we released an open source BlueSky prototype on GitHub under the Apache 2.0 license 🔌💡
github.com/EIAgov/BlueSky
🧵👇
Today, as a first step, we released an open source BlueSky prototype on GitHub under the Apache 2.0 license 🔌💡
github.com/EIAgov/BlueSky
🧵👇
GitHub - EIAgov/BlueSky
Contribute to EIAgov/BlueSky development by creating an account on GitHub.
github.com
October 31, 2024 at 7:05 PM
Project BlueSky is an EIA initiative to develop a next generation energy systems model.
Today, as a first step, we released an open source BlueSky prototype on GitHub under the Apache 2.0 license 🔌💡
github.com/EIAgov/BlueSky
🧵👇
Today, as a first step, we released an open source BlueSky prototype on GitHub under the Apache 2.0 license 🔌💡
github.com/EIAgov/BlueSky
🧵👇
Behold, EIA developed a new Sankey diagram to represent the U.S. energy system! 🔌💡 www.eia.gov/totalenergy/...
🧵👇
🧵👇
October 29, 2024 at 5:17 PM
Behold, EIA developed a new Sankey diagram to represent the U.S. energy system! 🔌💡 www.eia.gov/totalenergy/...
🧵👇
🧵👇
This week, EIA released its Winter Fuels Outlook, which estimates household energy expenditures for the upcoming winter.
tl;dr: Expenditures are expected to be about the same as last winter. Lower prices compensate for a slightly colder winter. 🔌💡
See more here:
www.eia.gov/outlooks/ste...
tl;dr: Expenditures are expected to be about the same as last winter. Lower prices compensate for a slightly colder winter. 🔌💡
See more here:
www.eia.gov/outlooks/ste...
October 11, 2024 at 7:48 PM
This week, EIA released its Winter Fuels Outlook, which estimates household energy expenditures for the upcoming winter.
tl;dr: Expenditures are expected to be about the same as last winter. Lower prices compensate for a slightly colder winter. 🔌💡
See more here:
www.eia.gov/outlooks/ste...
tl;dr: Expenditures are expected to be about the same as last winter. Lower prices compensate for a slightly colder winter. 🔌💡
See more here:
www.eia.gov/outlooks/ste...
Hurricane Milton is already affecting Florida’s energy infrastructure.
Some FL gas stations are without fuel given high demand. Fuel must be delivered by truck or ship.
Also, Port Tampa Bay is currently closed. 43% of FL’s petroleum products move through the port. 🔌💡
www.eia.gov/todayinenerg...
Some FL gas stations are without fuel given high demand. Fuel must be delivered by truck or ship.
Also, Port Tampa Bay is currently closed. 43% of FL’s petroleum products move through the port. 🔌💡
www.eia.gov/todayinenerg...
Hurricane Milton nears landfall on Florida’s west coast, disrupts energy infrastructure - U.S. Energy Information Administration (EIA)
www.eia.gov
October 9, 2024 at 7:38 PM
Hurricane Milton is already affecting Florida’s energy infrastructure.
Some FL gas stations are without fuel given high demand. Fuel must be delivered by truck or ship.
Also, Port Tampa Bay is currently closed. 43% of FL’s petroleum products move through the port. 🔌💡
www.eia.gov/todayinenerg...
Some FL gas stations are without fuel given high demand. Fuel must be delivered by truck or ship.
Also, Port Tampa Bay is currently closed. 43% of FL’s petroleum products move through the port. 🔌💡
www.eia.gov/todayinenerg...
EIA's Today in Energy (10/3/24) analyzes the impact of load growth in ERCOT driven by cryptocurrency mining and data centers.
We look at 3 demand cases for 2025 and estimate grid impacts 🔌💡: www.eia.gov/todayinenerg...
We look at 3 demand cases for 2025 and estimate grid impacts 🔌💡: www.eia.gov/todayinenerg...
Data centers and cryptocurrency mining in Texas drive strong power demand growth - U.S. Energy Information Administration (EIA)
www.eia.gov
October 3, 2024 at 9:11 PM
EIA's Today in Energy (10/3/24) analyzes the impact of load growth in ERCOT driven by cryptocurrency mining and data centers.
We look at 3 demand cases for 2025 and estimate grid impacts 🔌💡: www.eia.gov/todayinenerg...
We look at 3 demand cases for 2025 and estimate grid impacts 🔌💡: www.eia.gov/todayinenerg...
Hurricane Helene is affecting energy infrastructure along the U.S. Gulf Coast.
Trade press reports indicate that multiple companies have evacuated staff at offshore oil platforms and paused some production in the Gulf of Mexico. More here: www.eia.gov/todayinenerg...
🔌💡
Trade press reports indicate that multiple companies have evacuated staff at offshore oil platforms and paused some production in the Gulf of Mexico. More here: www.eia.gov/todayinenerg...
🔌💡
Category 3 Hurricane Helene nears landfall, disrupts energy infrastructure - U.S. Energy Information Administration (EIA)
www.eia.gov
September 26, 2024 at 1:47 PM
Hurricane Helene is affecting energy infrastructure along the U.S. Gulf Coast.
Trade press reports indicate that multiple companies have evacuated staff at offshore oil platforms and paused some production in the Gulf of Mexico. More here: www.eia.gov/todayinenerg...
🔌💡
Trade press reports indicate that multiple companies have evacuated staff at offshore oil platforms and paused some production in the Gulf of Mexico. More here: www.eia.gov/todayinenerg...
🔌💡
For all the long-term energy modelers out there: we just released an open source tool that allows you to plot projections from past editions of the Annual Energy Outlook against actual outcomes: github.com/EIAgov/dash-...
Let me explain why this is important. 🔌💡
Let me explain why this is important. 🔌💡
GitHub - EIAgov/dash-benchmark
Contribute to EIAgov/dash-benchmark development by creating an account on GitHub.
github.com
September 13, 2024 at 4:40 PM
For all the long-term energy modelers out there: we just released an open source tool that allows you to plot projections from past editions of the Annual Energy Outlook against actual outcomes: github.com/EIAgov/dash-...
Let me explain why this is important. 🔌💡
Let me explain why this is important. 🔌💡
I know you're all going to miss the early 2000s vibe on the EIA homepage (goodbye carousel and sidebars 👋), but it was time for a refresh...
www.eia.gov
There's *much* more to do, but it's a start.
www.eia.gov
There's *much* more to do, but it's a start.
Homepage - U.S. Energy Information Administration (EIA)
www.eia.gov
September 12, 2024 at 7:26 PM
I know you're all going to miss the early 2000s vibe on the EIA homepage (goodbye carousel and sidebars 👋), but it was time for a refresh...
www.eia.gov
There's *much* more to do, but it's a start.
www.eia.gov
There's *much* more to do, but it's a start.
The U.S. share of electric and hybrid vehicle sales increased in the second quarter of 2024 (2Q24).
BEVs represented 7.1% of light duty sales in 2Q24, about the same as last year. Tesla's market share dropped to 48.9% in 2Q24, first time below 50% since 4Q17.
www.eia.gov/todayinenerg...
🔌💡
BEVs represented 7.1% of light duty sales in 2Q24, about the same as last year. Tesla's market share dropped to 48.9% in 2Q24, first time below 50% since 4Q17.
www.eia.gov/todayinenerg...
🔌💡
U.S. share of electric and hybrid vehicle sales increased in the second quarter of 2024 - U.S. Energy Information Administration (EIA)
www.eia.gov
August 26, 2024 at 8:24 PM
The U.S. share of electric and hybrid vehicle sales increased in the second quarter of 2024 (2Q24).
BEVs represented 7.1% of light duty sales in 2Q24, about the same as last year. Tesla's market share dropped to 48.9% in 2Q24, first time below 50% since 4Q17.
www.eia.gov/todayinenerg...
🔌💡
BEVs represented 7.1% of light duty sales in 2Q24, about the same as last year. Tesla's market share dropped to 48.9% in 2Q24, first time below 50% since 4Q17.
www.eia.gov/todayinenerg...
🔌💡
EIA estimates the U.S. will add nearly 63 GW of new capacity in the electric sector in 2024. The overwhelming majority -- 96% -- will be carbon-free.
☀️ Solar: 37 GW
🔋 Battery: 15 GW
🌬️ Wind: 7.1 GW
💧Nat Gas: 2.6 GW
⚛️ Nuclear: 1.1 GW
www.eia.gov/todayinenerg...
🔌💡
☀️ Solar: 37 GW
🔋 Battery: 15 GW
🌬️ Wind: 7.1 GW
💧Nat Gas: 2.6 GW
⚛️ Nuclear: 1.1 GW
www.eia.gov/todayinenerg...
🔌💡
U.S. power grid added 20.2 GW of generating capacity in the first half of 2024 - U.S. Energy Information Administration (EIA)
www.eia.gov
August 22, 2024 at 8:38 PM
EIA estimates the U.S. will add nearly 63 GW of new capacity in the electric sector in 2024. The overwhelming majority -- 96% -- will be carbon-free.
☀️ Solar: 37 GW
🔋 Battery: 15 GW
🌬️ Wind: 7.1 GW
💧Nat Gas: 2.6 GW
⚛️ Nuclear: 1.1 GW
www.eia.gov/todayinenerg...
🔌💡
☀️ Solar: 37 GW
🔋 Battery: 15 GW
🌬️ Wind: 7.1 GW
💧Nat Gas: 2.6 GW
⚛️ Nuclear: 1.1 GW
www.eia.gov/todayinenerg...
🔌💡