Hungary's battery storage revenue stack after PICASSO and MARI: arbitrage vs aFRR vs imbalance

Battery storage revenue in Hungary is a stack of streams: arbitrage on the HUPX power exchange, payments to hold reserve for the grid operator MAVIR, energy payments when that reserve is called, and sometimes a state contract. Since October 2026 reserve energy clears on European platforms, and imbalance is a risk to manage rather than a product.

HUPX is the Hungarian Power Exchange. MAVIR is Hungary's transmission system operator (TSO). FCR is frequency containment reserve. aFRR and mFRR are automatic and manual frequency restoration reserve. PICASSO and MARI are the European platforms that exchange aFRR and mFRR energy. Everything below is as of October 2026.

What revenue streams can a grid-scale battery earn in Hungary?

A battery in Hungary can sell energy in trading markets, sell reserve capacity to MAVIR, sell reserve energy when MAVIR activates it, and receive state support. Each stream pays differently and fills at a different speed.

The duration column is general market logic, not a MAVIR figure. Sources for the other cells are in the sections below.

When did MAVIR join PICASSO and MARI?

MAVIR accessed PICASSO on 1 October 2026 and MARI on 5 October 2026. ENTSO-E's PICASSO notice is dated 2 October and states the 1 October access. Its MARI note is dated 6 October and states 5 October.

MAVIR's own announcements, in Hungarian, agree. Its 1 October news item says Hungary's market moved to standard aFRR and mFRR products at 00:00 and connected to PICASSO at 02:00. Its 5 October item says MAVIR connected to MARI that day.

According to MAVIR's 3 September workshop slides, the programme also introduced standard balancing products and moved all settlements to euro (except renewable support schemes). The slides say Slovakia, Austria and Slovenia had already joined.

How does arbitrage on HUPX pay?

A battery buys power when the price is low and sells when it is high, and the spread minus losses is the revenue. HUPX runs the day-ahead auction, which is coupled with the rest of Europe, and a continuous intraday market that it launched in 2016, coupled through the European XBID framework (HUPX).

Day-ahead prices have been set per quarter-hour since delivery on 1 October 2025, and 60-minute contracts remain available (HUPX).

The spread can be wide. In April 2026, Photon Energy's dataset for Hungary shows day-ahead prices from minus 500 to 291.8 EUR/MWh, with a mean of 96.6. For a simulated 1 MW / 1 MWh battery it calculated 6,016.4 EUR per MW from day-ahead arbitrage alone, and 11,567.1 EUR per MW for a 1 MW / 2 MWh unit.

Treat those figures as a one-month simulation. Photon assumes ideal hourly operation, 94% round-trip efficiency and a standalone battery.

How does MAVIR buy FCR and aFRR capacity?

MAVIR buys reserve capacity in tenders and pays providers for the MW they hold available. Its system services page, in Hungarian, describes monthly, daily and intraday capacity tenders run through its BOSs system. Its tender results page lists monthly FCR and aFRR results for 2026.

The capacity procurement plan of 31 August 2026, in Hungarian, sets the volumes. For October 2026 it lists these average requirements:

• aFRR up: about 203 MW (monthly baseload 100 MW, monthly peak-load 70 MW, plus daily hourly products).
• aFRR down: about 262 MW.
• mFRR up: about 343 MW, of which 300 MW is a daily product.
• mFRR down: about 24 MW.
• FCR: 25 MW monthly plus 20 MW daily.

From 1 October 2026 MAVIR also offers quarter-hour intraday capacity products for downward aFRR and downward mFRR. The plan says the requirement figures are reviewed before each procurement round, so they move.

MAVIR's settlement page, in Hungarian, lists control-energy settlement for aFRR and mFRR but not for FCR. A new provider also needs MAVIR accreditation, and the system services page says most accreditations are paused until at least the second half of October 2026.

What prices did MAVIR award for reserve capacity in 2026?

The table gives, for each delivery month, the average of the awarded prices in MAVIR's monthly result sheets, weighted by awarded MW and by the days in each delivery block. It is this site's calculation, in HUF per MW per hour. Baseload covers 24 hours and peak-load 08:00 to 20:00.

October 2026, the first month tendered in euro, averaged EUR 27.4 per MW per hour for FCR, 6.2 for aFRR up baseload, 14.6 for aFRR up peak-load and 4.5 for aFRR down. The table covers monthly products only, so daily and intraday capacity and mFRR capacity are not in it. These are awarded prices, not a battery's income.

The series has no single direction. FCR rose more than four-fold from March to July and then held near 10,600 to 10,950. Downward aFRR peaked at 15,500 in May and fell to 2,930 by September. Baseload aFRR up fell to 1,590 in May and recovered to 4,150 by September. Nine months is too short to call a trend, and a battery's income depends on its own bids and available hours.

What did PICASSO change for aFRR energy?

PICASSO moved aFRR energy pricing from a national pay-as-bid method to a European one. MAVIR's slides describe the platform as optimising every four seconds and setting a cross-border marginal price (CBMP), with 225 prices in each 15-minute settlement period.

Bids from Hungarian providers are submitted from 12:00 on the day before delivery until 25 minutes before it. The slides add that an activation priced above the CBMP is still paid as bid, but it does not move the CBMP or the imbalance price.

For a battery, the practical effect is that aFRR energy now competes with other countries' bids. Argus reports that market participants expect Hungarian batteries to compete with Slovak ones, which can bid lower because they pay lower grid fees.

Prices can be sharp. Photon Energy's April 2026 data lists a maximum aFRR up activation price of 25,000 EUR/MWh in Hungary against a mean of 180.5. Its simulated aFRR up activation income for a 1 MW / 1 MWh battery was 7,197.0 EUR per MW (net of recharging cost), against 238.8 EUR per MW for reservation. One month shows no trend, but it shows how unevenly the two parts of aFRR pay.

What did MARI change for mFRR?

MARI links Hungary's mFRR energy market to the other member countries, which now exchange this energy through one platform. MAVIR's slides planned the first MARI exchange for 09:00 on 5 October at the earliest, on the Slovak, Austrian and Slovenian borders.

mFRR clears with two product types, which the slides label SA and DA (scheduled and direct activation in the European standard). Marginal prices from these feed the Hungarian imbalance price. Capacity for mFRR is still bought by MAVIR in its own tenders, with 300 MW of the 343 MW average upward requirement in October bought as a daily product.

Is imbalance a revenue stream for a battery?

Imbalance is a settlement, not a product, and for a battery it is mainly a cost to manage. Each balance responsible party (BRP) that deviates from its schedule pays or receives one price. MAVIR's methodology page, in Hungarian, describes a single-price method. The starting price follows the system direction and the cost of activated reserve, and an incentive element compared with the HUPX day-ahead price encourages parties to close positions before real time.

From the 1 October 2026 business day the price is built differently. According to MAVIR's slides, it uses cross-border and marginal prices weighted by volume over the 15-minute period, with a local avoided-activation value as a last resort. Settlement is in euro, and the price is published about 30 minutes after the period ends. Argus reports that MAVIR chose an average rather than marginal pricing so a four-second spike would not set the whole 15-minute price.

Volatility is the open question. Asked in the workshop, MAVIR said it would see after go-live. Argus reported that market participants expect joining to change imbalance price volatility and battery revenue, not wholesale prices directly.

History is a warning too. Montel wrote in March 2024 that Hungary's system was long (needing downward balancing) in about 80% of quarter-hours over seven consecutive months, and that the price incentives favoured staying long. MAVIR has changed the rules since, so that period shows the risk, not today's level.

Are there contracted or state-backed revenues?

Yes, mainly through a 2023 state scheme. The European Commission approved a €1.1 billion Hungarian scheme for at least 800 MW / 1,600 MWh of storage in June 2023. It combines an investment grant with a two-way CfD for the first ten years of operation. The eligibility rules, the support calculation and the levy that funds it are in METÁR vs METÁROLÓ vs KÁT.

ESS News reports that Greenvolt's 99.8 MW / 288.6 MWh Buj project, fully operating in June 2026, has a ten-year cap-and-floor contract from a government auction, with merchant exposure afterwards. It also reports a HUF 11.3 billion grant.

How does co-location with solar change the stack?

A battery behind a solar park's grid connection shares one export limit with the park. It can charge from the park in low-price hours and sell later, which is the arbitrage stream with a cheaper charging input. How far midday prices fall is in the article on the solar capture rate in Hungary. How shared connections work is in the article on wind, solar and BESS on one grid connection.

SolServices and Huawei Technologies Hungary signed a 150 MW / 300 MWh battery agreement on 30 September 2026, with full operation targeted for Q1 2027 (Hungary Today, MTI). The reasons are set out in why SolServices is adding battery storage.

Serving reserve has an opportunity cost in arbitrage. In Photon Energy's April 2026 model, day-ahead income for a standalone 1 MW / 1 MWh battery fell from 6,016.4 EUR per MW to 4,021.6 once it also served aFRR.

How could the market saturate?

Reserve markets are small compared with the battery fleet now being built, and trading spreads are shared by all batteries. MAVIR data reported by CEENERGYNEWS put installed battery capacity above 700 MW (over 1,400 MWh) on 29 July 2026. Argus reported 984 MW at the beginning of September, up from 146 MW at the end of 2025, and said developers know the market will inevitably saturate as more batteries connect. The two fleet figures come from different sources and dates.

MAVIR's October 2026 average needs are below 350 MW for each product. The two numbers are not like for like, because not every battery is accredited and needs vary by hour. On that comparison the small reserve markets look the most exposed to a growing fleet, although the 2026 results above do not yet show a uniform price fall.

Supply, demand and competition pull in different directions:

1. More supply. Each new battery adds bids to capacity tenders, energy markets and trading spreads.
2. More demand, with limits. PICASSO and MARI let Hungarian providers serve foreign demand. MAVIR planned stepwise limits on this exchange but had not published them on 3 September.
3. More competitors. Argus reports that Slovak batteries can bid lower because they pay lower grid fees. Romania and Croatia are set to join PICASSO in Q2 2027 according to Argus.

What this means for solar park owners and investors

The stack is wider after PICASSO and MARI, and the small reserve markets are the most exposed to a growing fleet. Checks for anyone comparing storage cases:

• Separate the streams. Arbitrage is open-ended, reserve capacity is small, and reserve energy now prices off European platforms. Each should carry its own assumption.
• Do not add them up. A battery cannot sell the same MW in two uses in the same period. Photon's model shows day-ahead income falling when aFRR is added.
• Use awarded prices, not headline needs. MAVIR's monthly results show reserve capacity prices moving several-fold in nine months. A case built on one month's price is fragile.
• Check duration against product. Monthly baseload aFRR keeps power available all day. Longer duration earns more from arbitrage but costs more per MW.
• Treat imbalance as a risk line. The new method has no published track record.
• Re-check the numbers. MAVIR revises its requirement plan, and most accreditations were paused until at least the second half of October 2026.