Near-free at the margin.
The solar-installation subsidy stack defrays the cost of the rainwater layer to the point where the water infrastructure approaches free.
The economic insight at the centre of the memorandum
Solar photovoltaic panels installed for energy generation are also the rainwater catchment surface. Tilted, glass-fronted, hydrophobic, self-cleaning. The Spanish IDAE NextGen 30% subsidy and the EU NextGen Climate Fund already absorb a meaningful share of the solar layer CAPEX. The water layer bolts on at incremental cost, engineered to EU Drinking Water Directive 2020/2184 compliance.
The economic consequence is unusual and material: the solar-installation subsidy stack defrays the cost of the rainwater-catchment layer to the point where the water infrastructure approaches free at the margin. That sentence is the canonical thesis of the memorandum. It is not a marketing claim — it is an accounting outcome of stacking a state-funded solar incentive against an incremental engineering layer that shares the same surface, the same install crew, and the same permitting envelope.
The typical estate, in four numbers
These four numbers describe a typical Ibiza luxury estate at roughly 400 m² of contiguous roof — the realistic median of the addressable book. Larger estates scale proportionally: the combined system cost and the absolute annual saving both rise with roof area, while payback stays inside the same 3–5 year window. Larger roofs do not shorten the payback; they widen the absolute saving and the absolute subsidy capture. The geometry of the curve is consistent across the portfolio.
What Las Lluvias earns on a single installation
Revenue is itemised, never bundled. Each installation carries distinct lines — design and engineering, registration and compliance, subsidy capture across the IDAE NextGen, regional and municipal layers, and certification consulting against the EU DWD, Passivhaus and BREEAM standards. The bundle obscures the unit economics; the itemisation is the unit economics.
On top of the consultancy lines sit the hardware install margin and an optional ongoing certification subscription — the recurring layer that converts a one-off install into a relationship. Villa-scale and hotel-scale installations occupy distinct brackets, the latter reflecting larger roof areas, more demanding storage geometry, and commercial-grade certification. The per-line economics and project-value brackets are shared with qualified investors under confidentiality.
The layers, named honestly
The subsidy stack is real, layered, and currently favourable. It is also time-bound. Each layer must be named with its scheme of origin and its current state, never aggregated into a single optimistic percentage.
- Spanish IDAE NextGen — residential solar self-consumption (RD 244/2019 framework, NextGen funding envelope). Currently absorbing ~20–30% of solar CAPEX on qualifying residential installations. Wind-down risk: 2027–2028 as the NextGen allocation depletes; future framework not yet legislated.
- EU NextGen Climate Fund — variable per project, eligibility dependent on building-performance certification and regional disbursement schedule
- Regional Balearic incentives — Decreto-Ley 1/2020 drought-emergency framework and successor instruments, typically targeting rainwater capture and water-efficiency upgrades
- Municipal deductions — IBI and ICIO reductions vary by municipio; Santa Eulàlia, Sant Joan and Sant Josep each operate distinct schedules
Stacked, the total subsidy bandwidth currently sits at ~20–35% of solar CAPEX defrayed. The honest framing: the upper end of that range is what makes the water-layer-near-free thesis work today. If the IDAE NextGen layer winds down in 2027–2028 without a successor, the arithmetic tightens. The Year 1 Ibiza-only pilot programme is sized to land inside the current window.
Savings-based financing — the instrument being developed
One of the revenue layers being explored is a savings-based financing instrument. The design intent is that the household pays for the system from the certified saving it produces — the water and electricity bill that no longer arrives — rather than from new household cash. The system would be capitalised against the verified annual saving, and the household would route what it would otherwise pay the utility into the financing layer until the instrument retires.
If the instrument matures, it converts the unit-economics conversation from a CAPEX question into a cash-flow question — which is the question the luxury homeowner is more comfortable answering. Until then, every installation in the Year 1 cohort is sized to clear on the unfinanced 3–5 year payback alone.
The pre-seed round
Las Lluvias is raising a pre-seed round to fund the first year of Ibiza-only operations — the proof cohort of installations, the IP filing programme, EU Drinking Water Directive certification of the treatment system, and the first technical hires.
Round size and terms are shared with qualified investors under confidentiality. Active conversations are underway with strategic operators and angels whose expertise sits directly adjacent — luxury Ibiza construction, climate-tech infrastructure, and venture engineering.
Investors — request the confidential memorandum and current terms at [email protected].