1001 Smart Cities
🇫🇮 Helsinki

Suvilahti Solar Power Plant (Panel Rental)

🤖 AI-generated summary of the sources below · 🔎 Last verified · ◆ 7 sourced claims, none individually verified yet

This overview was generated with AI from the public sources listed below and checked against them before publication. It has not had a complete human fact-check — treat it as a starting point and follow the sources.

How this atlas is made · What “last verified” means · What “source-checked” means · The full record behind this page

✎ Corrected 27 Aug 2026 Publication date recorded for 4 sources. What changed →

Helen built Finland's largest solar plant to date on the old Suvilahti gasworks site: about 1,200 rooftop panels that residents without a roof of their own could rent for a monthly fee, with the panel's output credited against their bill. The utility announced the scheme in July 2014 and reported a couple of hundred rentals in the first hour; more than 900 panels had been booked by early October, when the first formal rental agreements were signed. Production started in March 2015, and a 2018 wall-mounted addition grew capacity to 363.52kWp.

Live 📅 since 2015
Outcome🎯 Succeeded
Evidence🏛️ Official
what does this mean?The strongest source is the operator's or the city's own reporting — an official report, dataset or press release. It grades who did the looking — not how well the project went. All four grades →
Run byHelen
Scale🏘️ District

📊 Impact

Helen reported a couple of hundred panels rented in the first hour and more than 900 of about 1,200 booked by early October 2014, saying it had met its sales targets. The plant produces roughly 275MWh a year, comparable to the annual consumption of around 100+ one-bedroom apartments.

🎓 Lesson

Read the price before the panel. Renting one cost EUR 4.40 a month and returned an estimated EUR 1 a month of electricity — so the renter pays more each month than the panel returns, buying an association with a solar plant on subscription rather than an investment, and Helen said as much in the figures it published. That is also why it sold: the product asks for a small monthly sum from people who have no roof to put a panel on, not for capital. And the sell-out is worth dating precisely — a couple of hundred in the first hour is a launch-day fact, while filling 1,200 panels took months.

⚡ EnergySolar & PVSmart grid & energy

Sources

↗ Helen (operator) — Solar power production started in the Suvilahti district of Helsinki (18 March 2015)Official launch release: commissioning date, 340kW capacity, 1,188 panels, ~275MWh/year.
↗ Helen (operator) — Aurinkoseinä: solar wall expansion at Suvilahti (11 May 2018)2018 solar-wall expansion: +23.52kWp / 84 panels, total 363.52kWp.
↗ pv magazine (independent trade press)Published 12 May 2015Independent confirmation of 340kW capacity and 'Finland's largest PV system' framing.
↗ Yle (independent press)Published 6 October 2014Published 6 October 2014, and the source for how the rental actually sold. Helen's unit manager Perttu Lahtinen: 'When we launched the service, we had a couple hundred sales in the first hour.' Advance bookings had 'exceeded 900' of about 1,200 panels by the date of the article, and formal rental agreements began that Monday. Also the economics: a monthly rental fee of EUR 4.40 against an estimated EUR 1 a month of electricity credited back, and about 285 watts per panel.

📅 How old is the evidence?

Two clocks, kept apart: when this entry’s sources were published, and what has happened to its record in the atlas. Documented span: since 2015. 4 of 4 sources carry a publication date, from 6 October 2014 to 11 May 2018.

When the sources were published

  1. Yle · pressYle (independent press)
  2. Helen Oy · utilityHelen (operator) — Solar power production started in the Suvilahti district of Helsinki (18 March 2015)
  3. pv magazine International · presspv magazine (independent trade press)
  4. Helen Oy · utilityHelen (operator) — Aurinkoseinä: solar wall expansion at Suvilahti (11 May 2018)

Every source, with links ↑

What happened to this record

  1. Publication date recorded for 4 sources
  2. Entered the record
  3. Sources last read

Every revision, permanent →

Show your work What this page rests on and what it can’t tell you · all 7 claims with their sources · the forensic record

Evidence Passport · public beta 7 addressable claims, 4 source dossiers, one permanent baseline. The passport is unreviewed — an AI-assisted structural migration, not a human or expert endorsement. Every revision keeps a permanent copy under revision history.

Inspect the claims, one by one — verbatim text, sources and caveats for all 7

The text below is copied verbatim from the published record. Each claim names the source dossiers that carry it; caveats stay attached to the claim they qualify.

Claim 1 clm-fb1cec8125b67473 descriptive
Helen built Finland's largest solar plant to date on the old Suvilahti gasworks site
Published field
snippet · verbatim
Mapping
mapped · no interpretation or interpolation added by this passport
What the mapping says
pv magazine, 12 May 2015, on work underway on 'Finland's largest PV system'; Helen's own launch release gives the Suvilahti gasworks site and the 340 kW capacity.
Caveat
No claim-specific caveat recorded

Sources carrying this claim

  1. pv magazine (independent trade press)
  2. Helen (operator) — Solar power production started in the Suvilahti district of Helsinki (18 March 2015)
Claim 2 clm-d63dda920ebe4490 quantitative
about 1,200 rooftop panels that residents without a roof of their own could rent for a monthly fee, with the panel's output credited against their bill
Published field
snippet · verbatim
Mapping
mapped · no interpretation or interpolation added by this passport
What the mapping says
Yle: 'The project involves 1,200 solar panels' and 'The agreement allows Helsinki Energy customers to rent solar panels, the output from which is then deducted from the customer's monthly electricity consumption.' Helen's release gives 1,188 panels and 340 kW.
Caveat
No claim-specific caveat recorded

Sources carrying this claim

  1. Yle (independent press)
  2. Helen (operator) — Solar power production started in the Suvilahti district of Helsinki (18 March 2015)
Claim 3 clm-965123111d600e6d quantitative
The utility announced the scheme in July 2014 and reported a couple of hundred rentals in the first hour; more than 900 panels had been booked by early October, when the first formal rental agreements were signed
Published field
snippet · verbatim
Mapping
mapped · no interpretation or interpolation added by this passport
What the mapping says
Yle, 6 October 2014: 'In July the utility announced that it would be installing solar panels on the rooftop of a power substation'; 'When we launched the service, we had a couple hundred sales in the first hour'; 'Advance bookings so far have exceeded 900 and the utility began offering formal rental agreements from Monday.'
Caveat
No claim-specific caveat recorded

Sources carrying this claim

  1. Yle (independent press)
Claim 4 clm-94c55053c2d56202 quantitative
Production started in March 2015, and a 2018 wall-mounted addition grew capacity to 363.52kWp
Published field
snippet · verbatim
Mapping
mapped · no interpretation or interpolation added by this passport
What the mapping says
Helen's release of 18 March 2015 announces that solar power production had started at Suvilahti; the release of 11 May 2018 adds a solar wall of 84 panels and 23.52 kWp, taking the total to 363.52 kWp.
Caveat
No claim-specific caveat recorded

Sources carrying this claim

  1. Helen (operator) — Solar power production started in the Suvilahti district of Helsinki (18 March 2015)
  2. Helen (operator) — Aurinkoseinä: solar wall expansion at Suvilahti (11 May 2018)
Claim 5 clm-5487f9cdf06d3287 quantitative
Helen reported a couple of hundred panels rented in the first hour and more than 900 of about 1,200 booked by early October 2014, saying it had met its sales targets
Published field
impact · verbatim
Mapping
mapped · no interpretation or interpolation added by this passport
What the mapping says
Yle quotes Helen's unit manager on both the first hour and the running total, and: 'We have reached our sales targets and are very satisfied.'
Caveat
No claim-specific caveat recorded

Sources carrying this claim

  1. Yle (independent press)
Claim 6 clm-71f2575f6d7dc48f quantitative
The plant produces roughly 275MWh a year
Published field
impact · verbatim
Mapping
mapped · no interpretation or interpolation added by this passport
What the mapping says
Helen's launch release gives an expected annual output of about 275 MWh.
Caveat
An operator figure for expected annual output rather than a metered result.

Sources carrying this claim

  1. Helen (operator) — Solar power production started in the Suvilahti district of Helsinki (18 March 2015)
Claim 7 clm-fefcd93b80eb5fab quantitative
Renting one cost EUR 4.40 a month and returned an estimated EUR 1 a month of electricity
Published field
lesson · verbatim
Mapping
mapped · no interpretation or interpolation added by this passport
What the mapping says
Yle: 'For a monthly rental fee of 4.40 euros, customers will see the output of their solar panels deducted from electricity consumption on their monthly bills. The utility estimated that the electricity generated by one panel would correspond to about one euro each month, reducing the panel rental cost to 3.40 euros per month.'
Caveat
No claim-specific caveat recorded

Sources carrying this claim

  1. Yle (independent press)
Forensic record — source dossiers, gaps, hashes and the exact revision this page renders

This layer records what is known about each source, what is still missing, and the exact snapshot this page is rendering. A missing date, archive or hash stays visible as missing.

unreviewed Revision 2026-08-27-editorial-review effective 2026-08-27 · created 2026-08-27

Awaiting operator and domain-expert review; publication of this revision implies neither.

sha256:70147498059d5f130a12557469cd21a9bec930ca3547275b05a47d2376ea2de3
Revision history → Permanent version link → Machine-readable record → Evidence Constitution →
7
of 7 claims mapped
4
source dossiers
4
publication dates recorded
0
archives linked
0
exact locators
0
content captures hashed

Governance facts carried by the record

Operator
Helen
Actor types
utility
Funding model
utility
Funding description
Not recorded
Cost
Not recorded
Ownership
Not recorded
Decision rights
Not recorded
Exit conditions
Not recorded

4 source dossiers

Helen (operator) — Solar power production started in the Suvilahti district of Helsinki (18 March 2015) helen.fi · 4 linked claims

Open original source ↗

Stable source ID
src-8d1b2b9891db732f
Publisher
Name not classified · helen.fi
Type / language
web-page · language not classified
Published
2015-03-18
Updated
Not recorded
Source last checked
No source-level check date
Record last verified
2026-08-27
Dossier created
2026-08-27
Retrieved copy
No local capture recorded
Archive
No archived copy linked
Content hash
No captured content hash
Locator
Open the recorded source note

Official launch release: commissioning date, 340kW capacity, 1,188 panels, ~275MWh/year.

Descriptive only — not page/paragraph exact
Claims linked
Helen (operator) — Aurinkoseinä: solar wall expansion at Suvilahti (11 May 2018) helen.fi · 1 linked claim

Open original source ↗

Stable source ID
src-732a813e008d3dfe
Publisher
Name not classified · helen.fi
Type / language
web-page · language not classified
Published
2018-05-11
Updated
Not recorded
Source last checked
No source-level check date
Record last verified
2026-08-27
Dossier created
2026-08-27
Retrieved copy
No local capture recorded
Archive
No archived copy linked
Content hash
No captured content hash
Locator
Open the recorded source note

2018 solar-wall expansion: +23.52kWp / 84 panels, total 363.52kWp.

Descriptive only — not page/paragraph exact
Claims linked
pv magazine (independent trade press) pv-magazine.com · 1 linked claim

Open original source ↗

Stable source ID
src-b66f6e3133aae210
Publisher
Name not classified · pv-magazine.com
Type / language
web-page · language not classified
Published
2015-05-12
Updated
Not recorded
Source last checked
No source-level check date
Record last verified
2026-08-27
Dossier created
2026-08-27
Retrieved copy
No local capture recorded
Archive
No archived copy linked
Content hash
No captured content hash
Locator
Open the recorded source note

Independent confirmation of 340kW capacity and 'Finland's largest PV system' framing.

Descriptive only — not page/paragraph exact
Claims linked
Yle (independent press) yle.fi · 4 linked claims

Open original source ↗

Stable source ID
src-ed3c8aac6dd2a266
Publisher
Name not classified · yle.fi
Type / language
web-page · language not classified
Published
2014-10-06
Updated
Not recorded
Source last checked
No source-level check date
Record last verified
2026-08-27
Dossier created
2026-08-27
Retrieved copy
No local capture recorded
Archive
No archived copy linked
Content hash
No captured content hash
Locator
Open the recorded source note

Published 6 October 2014, and the source for how the rental actually sold. Helen's unit manager Perttu Lahtinen: 'When we launched the service, we had a couple hundred sales in the first hour.' Advance bookings had 'exceeded 900' of about 1,200 panels by the date of the article, and formal rental agreements began that Monday. Also the economics: a monthly rental fee of EUR 4.40 against an estimated EUR 1 a month of electricity credited back, and about 285 watts per panel.

Descriptive only — not page/paragraph exact
Claims linked
Known limits of this passport
  • Publisher names and source languages have not yet been classified; domains are recorded without guessing.
  • Existing source notes are descriptive locators, not page- or paragraph-exact citations.
  • A missing archive, publication date or content hash is shown as null rather than inferred.
  • The project-level evidence grade ranks the strongest source in the entry; it is not a truth score for every claim.

Continue exploring

Compare this project

🇦🇹 Vienna's Citizens' Solar & Wind Power Plants · Vienna Vienna's Bürgerkraftwerke let 12,200+ residents co-own solar/wind plants since 2012; Suvilahti instead rents utility-owned panels for a fee. 🇯🇵 Tokyo Bay eSG Project · Tokyo Two urban solar builds: Suvilahti's rooftop PV let residents rent panels; Tokyo Bay's offshore floating array (2024) survived a typhoon. 🇦🇪 Shams Dubai Rooftop Solar · Dubai Two distributed-solar models: Suvilahti rents panels to residents; Dubai's Shams Dubai net-meters owner-installed rooftops instead.

Who gets the money out of a rooftop

Rooftop solar is the one energy asset a resident can own, and these four cities answer very differently who is allowed to own it and who collects. The awkward finding is common to all of them: the schemes reach the roofs that were already there.

ProjectSinceStatusOutcomeEvidenceRun byCostWho owns the panel, who gets paid
Cash for Power: Cape Town Buys Back Rooftop SolarCape Town, 🇿🇦 2023 Live Ongoing Official Utility or public operator R55M paid to sellers to Jan 2025 (City figure); bidirectional meter R6,043 incl VAT borne by the customer The resident owns it and can take cash, not just bill credit — but only with a roof, the capital for an array and a City account, so the money moves upward.
Vienna's Citizens' Solar & Wind Power PlantsVienna, 🇦🇹 2012 Live Ongoing Official Utility or public operator €40m+ cumulative citizen investment since 2012 The utility owns and runs the plant; residents buy fixed shares of it and take a guaranteed return as vouchers against their own bill.
Suvilahti Solar Power Plant (Panel Rental)Helsinki, 🇫🇮 2015 Live Succeeded Official Utility or public operator not public The utility owns the panels and rents them by the month to people with no roof of their own, crediting each panel's output to that tenant.
Buiksloterham Positive Energy District (ATELIER)Amsterdam, 🇳🇱 2019 Completed Scaled back Independent City government ≈€19.6M (EU Horizon 2020 contribution) Nobody sold anything to anyone: the grid operator could supply a fraction of the connection capacity requested, and peer-to-peer trading became flexibility management.

Explore the wider context

☀️ Solar & PV guide🏙️ Helsinki city profile⚡ Energy projects📖 Microgrid📖 Smart grid📖 Building performance standard (BPS)
📎 Cite this project

1001 Smart Cities (2026). “Suvilahti Solar Power Plant (Panel Rental)” — Helsinki, Finland. The Smart City Atlas. https://1001smartcities.org/projects/helsinki-suvilahti-solar/ (last verified 2026-08-27). Data: CC BY 4.0.

The underlying data is free to reuse with attribution — see the open data page.

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