Stephen Jarvis

@stephenjarvis.bsky.social

5443 Followers 561 Following

Assistant Professor in Environmental Economics at LSE. Posting mostly about energy/enviro research. https://stephenjarvis.github.io/

Guardian political live blog post following Andy Burnham's speech as new Labour leader, reads: "Burnham claims he has not yet made any decisions about who will be in his 'top team' Earlier in the speech Burnham claimed he had not yet decided on key cabinet appointments. He said: 'Contrary to what you may keep on reading, I haven’t made any decisions yet about who will be in that top team, but I will soon. And when I have, you will see it reflects all parts of our party, all communities.'"
Picture of street in Washington DC with hazy smoke-filled skies.
Map showing observed or predicted residential air conditioning adoption shares for countries and subnational regions around the world.
Chart showing declining share of UK universities active and/or posting on X. In Feb 2025 roughly 90% were still active, but by May 2026 it is now less than 40%.
Plot showing the cumulative adjustment function from simulating the impact on the utility rate of return from a one percentage point shock to the underlying benchmark index. Here we compare approved rates of return and nominal 10-year US Treasuries as our benchmark rate. We plot the change in the nominal rate of return on equity over the subsequent six years. We find evidence of asymmetric adjustment. Rates of return adjust faster to a positive shock (solid line) than to a negative shock (dashed line). In the long run, both converge to a roughly 50% pass-through rate. The degree of asymmetric adjustment appears strongest in the rates of return that utilities propose, but is still present to a notable extent in the rates of return that regulators ultimately approve.
The plot shows return on equity (RoE) gap, by different CAPM benchmarks (percentage points for approved RoE minus estimated benchmark cost of capital). Lines show gap increases from around zero (or negative in 1980s) to steadily positive from 1990s to 2020s, with premium ranging from +0.5 to +5 percentage points in certain instances.
Figure plots the approved return on equity from our rate cases over the 40 year time period spanned by our sample. We also plot various risky and risk-free market rates for comparison. A couple of features jump out. The gap between the approved return on equity and other measures of the cost of capital has increased substantially over time. Consistent with a story where regulators adjust slowly, approved RoE has fallen slightly (in both real and nominal terms), but much less than other costs of capital. This is the key stylized fact that motivates our examination of the return on equity that utilities earn, the implications this may have for their incentives to invest in capital, and the costs they pass on to consumers.
Picture of DC union station
Picture of parliament and the London eye from next to the Thames
View standing on the sea wall by heysham nuclear power plant
Picture of iced coffee on a table
Average retail household electricity prices for select countries from 1990 to 2025. Can see UK used to be well below the EU average and Japan, similar to Korea and about 50% above the US. Has risen steadily since 2005 and now above EU average and Japan, and double US/Korea. Source: https://www.iea.org/reports/electricity-2026
Chart shows monthly average wholesale electricity prices for European countries from 2018 to 2026. Prices generally move closely together with a large common price spike in 2022. Spain/France somewhat lower in recent years due to fuel mix and policy interventions. UK generally middle of the pack and similar to Germany. Source: https://ember-energy.org/data/european-electricity-prices-and-costs/
Image of Micky Haller from The Lincoln Lawyer
Picture of LSE campus
Ad for Palantir Technologies on the DC metro with the tagline “software that dominates”
Chart shows electricity net load (demand net of renewables) in California over time. Can see net load getting lower and lower in the middle of the day as solar output increases over time.
Bike propped against a wall with the sea behind
Bar chart showing capacity for different power supply sources in GB. Purple is existing. Blue is proposed that will be prioritised by 2030. Green is proposed that will be prioritised by 2035. Can see Offshore Wind and Solar are largest with reformed queue meeting entire requirement. Onshore Wind still falls short of planned target. Despite a significant haircut of proposed projects, Batteries still has capacity 2-3x the original planned requirement.
Transport secretary Heidi Alexander rules out 'national pay-per-mile' scheme for electric vehicles in budget Heidi Alexander, the transport secretary, has said the government will not be introducing “a national pay-per-mile scheme” for the drivers of electric vehicles (EVs). Earlier this month the Daily Telegraph reported that a pay-per-mile scheme for EVs would be introduced in the budget. The paper said the scheme would come in from 2028 and that it would cost the average EV driver £250 a year. At the time the government did not confirm the story. But it did not deny it either, and it issued a statement saying that it wanted a “fairer” scheme that would compensate for the fact that fuel duty, the main tax for drivers, is only paid by people with petrol or diesel cars. Today Alexander ruled out a pay-per-mile scheme for EVs – at least on a national level.
Image shows rankings of top 10 professions with highest and lowers private school attendance. Average for UK population is 7%. Notably at the top end are armed forces (63%), senior judges (62%), shadow cabinet (52%), lords (52%), columnists (50%) etc. Notably at the bottom end are, footballers (4-5%), pop stars (10%), cabinet (7%), trade union leaders (12%), university vice chancellors (15%) etc.
Map showing wind farms across GB. Grey circles are based on the max capacity of the wind farm, with an inner yellow circle representing output. Lots of large yellow circles basically indicating wind farms operating close to their maximum capacity.
Screenshot of live stats from the GB power grid. Piechart for generation shows 70% wind/solar/hydro, 10% nuclear/biomass, 13% gas, 9% interconnectors and -2% storage. Prices currently £7.5/MWh and emissions at 59g/MWh.
Pie charts show the share of electricity demand in Laos going to different end-use sectors. In 2024 this is 39% industrial, 15% commercial/government/agriculture, 22% residential and 24% crypto.
xkcd comic on sports commentary. One presenter says "A weighted random number generator just provided a new batch of numbers". The other replies "Let's use them to build narratives!"
The prime minister’s first choice to take over Angela Rayner’s housing and local government responsibilities was Ed Miliband, but he refused to leave energy and climate change. This appears to have been the one part of the reshuffle that didn’t quite go Starmer’s way.
Picture of a park in east London on a Sunday afternoon with a cricket match being played.
Duty free section at a UK airport
Nesta figure showing heat pumps installed elsewhere adoption across Europe steadily increasing from less than 2 million in 2011 to 5 million in 2021. About 80% are air-to-air and 20% are air-to-water.
The dominance of neoclassical economics in our university curricula has created a world where we are told there is no alternative — only technical adjustments to a system that is fundamentally fair, rational and efficient. But this is fiction. Economics today resembles Catholic theology in medieval Europe: a rigid doctrine guarded by a modern priesthood who claim to possess the sole truth. Dissenters are shunned. Non-economists are told to “think like an economist” or not think at all. This is not education. It’s indoctrination.
Rethinking Economics, a group of activists that emerged from the post-crash student rebellion, recently took stock of the state of economics taught at UK universities in its curriculum health check. The findings are sobering. “The climate crisis and socio-ecological issues are broadly absent from economic curricula,” it found. Seventy-five per cent of universities “do not teach any ecological economics”. The report shows how the mainstream’s best-ranked universities often perform the worst in preparing students for the real world. We are training future economists to fail again.
Chart shows outturn balancing costs from 2018-2023. Constraint costs have roughly doubled, although receded slightly from peak during 2022 energy crisis.
Chart shows average residential prices by region in 2024 in GB. Meryside and North Wales is 32.5 p/kwh compared to 30.4 p/kwh in Yorkshire.
Comparison between GB and European wholesale electricity prices under national and nodal pricing. Under national GB has the highest average, but after nodal reforms most English/Welsh areas shift closer to the middle and Scottish areas become by far the lowest price.
Map showing interconnector interconnectors in 2040 overlayed on sub-national GB price changes after zonal pricing reforms.
Map of today's Nordpool prices showing variation across the 4 sub-regons within Norway (2-75 EUR/MWh) and the 4 sub-regions within Sweden (22-45 EUR/MWh)
Chart from Ofgem's locational pricing assessment showing rising cost of balancing costs. Part of the recent increase is due to the Ukraine crisis increasing gas prices, but the steady rise in constraint costs is also clear and expected to continue rising into the 2030s.
Picture of Cruachan Dam in Scotland
Picture of SFO international terminal
View from the train of the mountains
Chart shows annual number of UFO sightings in the UK from 1940 to the present. There is a large increase from the 1990s until the mid-2000s, after which there is a steady decline.
Chart shows traffic speeds during peak hours in New York City business district from September 2024 to March 2025. There is a substantial 20% increase in traffic speeds once congestion pricing is introduced in January.
Picture shows screenshot from dashboard of live grid data for Great Britain. Wind, solar and nuclear make up almost the entire generation mix with a very small amount of gas/biomass. Also substantial exports on the intereconnectors to France, Ireland and Norway.
Picture shows the view down the valley in Banff with the snow capped mountains in the distance.
Picture shows one of the wind turbines up close. The turbine is about 120m tall and several others can be seen off in the distance.
Video shows a boat heading out towards an offshore wind farm. The turbines can be seen turning in the distance before the camera pans to see the people standing at the front of the boat.
Bar chart showing average planning decision times from initial submission to first grant or refusal decision, this time weighted by project capacity. Results are broken down by technology type. Batteries have average decision times of approx 300 days with a slight increase in recent years. Similar story for solar with an average of 400 days. Offshore wind varies from year-to-year due to small number of projects, with average times ranging from approx 500-1000 days in most years. Onshore wind is consistently around 700-1000 days with no clear trend.
Bar chart showing average planning decision times from initial submission to first grant or refusal decision. Results are broken down by technology type. Batteries have average decision times of approx 250 days with no clear trend in recent years. Similar story for solar with an average of 150 days. Offshore wind varies from year-to-year due to small number of projects, with average times ranging from approx 500-1000 days in most years. Onshore wind is consistently around 500-700 days with no clear trend.
Table showing the imports and exports of electricity from each of the UK’s border connections. Currently they are serving 16% of UK supplies with most coming from France and Norway. Numbers are: Belgium 0.21GW 0.9% Denmark 0.00GW 0.0% France 3.00GW 12.8% Ireland −0.96GW −4.1% Netherlands 0.14GW 0.6% Norway 1.40GW 6.0%
Chart showing electricity supply in Spain over the past day (April 29th). After system recovered by 4am the majority of supply has come from hydro, wind and solar, with gas making up the remainder. Data runs until 10pm at which time demand is starting to fall.
Table showing estimated costs for different onshore grid transmission technologies. Data is as follows: 400 kV a.c. Overhead Line £1,186 400 kV a.c. Underground Cable £5,333 400 kV a.c. Cable in Tunnel £14,104 275 kV a.c. Pressurised Air Cable (2.3 GW) £3,952 132 kV a.c. Superconducting Cable (1.4 GW) £7,782 Reconductoring using HTLS a.c. conductor (75 km only) £1,981 Use of alternative a.c. tower technologies (15 km and 75 km, 4,988 MW double circuit rating) £1,731 Onshore HVDC VSC (2 GW, 700 km, single circuit) £2,273 Onshore HVDC LCC (8 GW, 700 km, single circuit) £1,679 UHV onshore a.c. transmission (8 GW, 700 km, single circuit) £883
Chart showing the total demand in the Spanish power grid during the day. Around midday there is a sudden drop from 25GW to 10GW. There is then a slow recovery from this level to 18GW in the last hour. Still well below the forecast level, but potentially on a trajectory to return to the forecast level overnight.
Prof Chenghong Gu, Department of Electronic & Electrical Engineering, University of Bath, explained: “High temperature, high humidity, rough conductor surfaces, can cause corona effects on transmission conductors. The current in these conductors produce electric fields, and they can interact with the electric charges in the ambient atmosphere. “Under certain conditions, this can cause the vibrations of conductors. Then, the vibrations can cause the changes of the physical characteristics of conductors, reflecting in their key parameters, such as their impedance, reactance. The stability of power systems is very sensitive to these parameters, and if they keep changing, currents in transmission lines, voltages in different locations, and system frequency would change. In the worst case, system frequency could drop too low, and customers must be cut off to re-balance the supply and demand.”
Chart showing grid system freqency in Great Britain today. The frequency line fluctuates around 50 Hz within the green operating frequency tolerance range.