Consumption

Electricity, zero prices on 1 May for six hours

The large production, especially from solar, with the low demand on the public holiday lowers the values

by Sara Deganello

1 May 2026

3' min read

Translated by AI

Versione italiana

Key points

More supply, less demand
How the price is formed
The consequences for the development of renewables

3' min read

Translated by AI

Versione italiana

Electricity, on 1 May throughout Italia, the single national price (Pun Gme Index) touched the value of zero euro per MWh between about 11 a.m. and 5 p.m.. A value that also brought down the daily average: from 106 euros per MWh on 30 April to 87 on 1 May.

The phenomenon had already occurred in the past few days in the southern regions and islands, and was recorded in the zonal piece, which was different for each macro-area.

More supply, less demand

The first time values fell to zero across the country was on 1 May last year. And this is no coincidence: the public holiday - with factories and offices closed - brings with it a lower need for electricity, hence a low demand. In addition, from a seasonal point of view, the widespread use of air conditioners, which traditionally push up energy consumption during the summer, has not yet begun. On the other hand, the warm season pushes the production of energy from the sun to the maximum, resulting in a high supply, higher than the actual demand for electricity in the country.

This leads to two consequences: the collapse of prices during the hours of overproduction in the electricity exchange managed by the Gme - the platform where producers and operators exchange energy on an hourly basis (or rather, since last year on 15-minute slots) to cover the country's needs - and curtailment, i.e. the shutdown of some plants imposed (and remunerated) by the grid operator who is responsible for keeping the electricity system in balance (in which supply and demand must be equal).

As the Gme results show, prices on 1 May 2026 started the day with a value of 122 euros per MWh at 1am, touching 140 euros per MWh at 6am. Then, the descent: 129 at 8 a.m., 100 at 9 a.m., 2 euros per MWh at 10 a.m. At 11 a.m., the price is at zero and starts to rise again at 6 p.m. to 7 euros per MWh, rising to 126 at 7 p.m., 145 at 9 p.m. and 149 at 11 p.m. before closing at 140.

How the price is formed

In the day-ahead market (Mgp) system, energy producers and consumers submit their offers to buy or sell energy for the next day, indicating the quantities they are willing to sell or buy and the associated price. The manager of the energy markets (Gme), who is responsible for managing it, creates an order of merit: it accepts the bids and lines them up, one after the other, from the cheapest to the most expensive, until the expected demand is satisfied. The last accepted offer is the marginal price for that time period. Renewables have dispatching priority, pushing more expensive conventional generation units, e.g. gas, out of the market. Obviously, they fail at night, leaving the marginal price to gas.

Zero or negative wholesale electricity prices - in Italia, it is currently not possible to go below zero - have been common in some parts of Europe for several years. In 2025, Spain recorded around 550 hours of negative prices, France over 500, Germany almost 600 (source: Gem Energy Analytics). Italia is not yet at those levels, quite the contrary.

The consequences for the development of renewables

While zero prices may bring relief in the bill, they do not help to support the development of renewables. If, for example, those plants that found themselves producing free electricity on 1 May had no incentive or fixed-price supply contracts, they would not have been remunerated. This means no revenue, a condition that can obviously discourage investment. Even if purely market-based plants are a minority part of the installed fleet.

There is a solution to this phenomenon: the development of batteries, i.e. systems that store energy when there is overproduction and less demand and release it into the grid when there is less production and more demand. Italia has taken a decisive step in the development of storage systems: last autumn Terna held the first auction of the Macse, a tool that remunerates the storage systems needed by the grid, especially in the south where there is the greatest development of renewables. The first deliveries, however, are scheduled for 2028.

Sara Deganelloredattrice
- LinkedIn
Luogo: Milano
Lingue parlate: italiano, inglese, tedesco
Argomenti: design, economia, cultura
Scheda autore
Trust project