SolarGPU

Courtesy translation. The Spanish text at solargpu.es/contrato is the one that applies.

Host contract: terms of the lease of use of the node

This is what you sign with SolarGPU. It is written to be understood without a lawyer, and under each clause we explain why it is there: almost all of them exist so that the agreement works, is legal and costs you neither an extra formality nor an extra tax.

Version 1.0, 16 September 2026. These terms summarise the contract you sign; in case of difference, the signed text prevails. They are not legal advice: how what you earn is taxed is explained in Host taxation.
What it is
Lease of use of your node (lease of movable property)
What you earn
A rent for every kWh the node consumes, at the rate of its class
Term
One year, renewable. You can leave whenever you want with 30 days' notice, without penalty
Who invoices
SolarGPU, on your behalf; you accept each invoice in the app
Who owns the node
Yours, before, during and after
  1. Who signs and what is leased
  2. What this contract is, and what it is not
  3. What SolarGPU does
  4. What you do
  5. The rent: how much, how it is measured, when it is paid
  6. The energy
  7. Invoices, VAT and withholding
  8. Referrals
  9. Term and end of the contract
  10. Warranty and breakdowns
  11. Liability
  12. Data and security
  13. Assignment of the contract
  14. Applicable law and changes

1Who signs and what is leased

The signatories are the host — the person or company that owns the node — and Acceleration Robotics S.L.U. (SolarGPU brand), Spanish tax ID B01952092, with registered office in Vitoria-Gasteiz. The host grants SolarGPU the exclusive use of a SolarGPU node identified by its serial number, installed at the address the host indicates, so that SolarGPU can operate it by offering compute and artificial intelligence services to third parties.

Why. The object of the contract is the machine, not your work or your electricity. That is what makes the Tax Agency treat you as a lessor and not as a business.

2What this contract is, and what it is not

  1. It is a lease of movable property (articles 1542 et seq. of the Spanish Civil Code), with a rent calculated according to use.
  2. It is not a provision of services by the host: the host carries out no activity, serves no one, and neither operates nor administers the node.
  3. It is not a sale of energy: the node consumes the host's electricity on the host's premises, and neither the host nor SolarGPU delivers energy to anyone (clause 6).
  4. It is not a company, a joint ownership or a silent partnership: the node is not contributed to anyone and remains the host's property.

Why. Each "it is not" closes a door that would cost you money: self-employed social security, electricity regulation and losing ownership of the equipment. See Taxation, point 1.

3What SolarGPU does

  1. Configures the node remotely, keeps it updated and secure, lists it on the compute marketplaces, sets the prices, serves the customers and collects payment from them. The commercial risk is SolarGPU's: if no one rents, no one gets paid, and the host owes nothing.
  2. Isolates customer workloads in containers or virtual machines and confines the node to its own network: it does not access other devices in the home or the host's network beyond what the node needs to reach the internet.
  3. Measures the node's consumption with its own meter and publishes in the app, for the host, the consumption, the hours of use and what the host is due.
  4. Issues the invoices on the host's behalf, applies and pays in the withholding, delivers the annual certificate and prepares the VAT returns (clause 7).
  5. Pays the rent every month by bank transfer to the host's account.

4What you do

  1. Keep the node plugged in, switched on and connected to the internet by cable, in a ventilated, dry place, with a compliant electrical installation.
  2. Not use the node for anything else, not connect peripherals to it or modify its software or hardware for the duration of the contract. This is the condition for the VAT deduction (Spanish VAT Act art. 95: exclusive use).
  3. Give notice in the app before switching it off or disconnecting it, except in an emergency, and report any breakdown or change of address.
  4. Allow SolarGPU remote access to the node (the node only) and, if a repair is needed, facilitate its collection and delivery.
  5. Declare whether they act as a private individual, self-employed person or company and whether the node is assigned to a business activity, and keep their tax details up to date (tax ID, address, account).
  6. Sign the tax census registration (Form 036) that SolarGPU prepares, if not already registered as a business for VAT purposes, and accept each invoice in the app.

Why. These are the four things the node's output depends on — power, network, space and time — and the two that the described tax treatment depends on: exclusive use and correct details.

5The rent: how much, how it is measured, when it is paid

  1. The rent is the product of the kilowatt-hours the node consumes during the month and the rate of its class (SG0.25, SG0.5, SG1, SG2, SG7 or SG70), according to the table published at solargpu.es/en/pricing on the date of signing or renewal. The current rate is recorded in the contract with its date.
  2. The rate does not change during the current contract year. The public table is reviewed every quarter according to the compute market; if at the annual renewal the class rate is different, SolarGPU gives 30 days' notice and the host can accept it or not renew, without penalty.
  3. Consumption is measured with the node's meter and shown in the app. While a node has no meter, consumption is estimated with a model and marked as estimated; the host can ask for the meter to be installed at any time.
  4. It is settled by calendar month. SolarGPU issues the invoice in the first days of the following month and pays by bank transfer within fifteen days of its acceptance. Amounts pending acceptance do not accrue interest.
  5. If the node does not consume because it is switched off, broken down or without network, there is no rent for that time: the rent follows use.

Why. A rent indexed to consumption is what makes the lease fair without anyone having to take anyone's word: the meter is in plain view of both. And the fixed rate per contract year is what guarantees it does not change for the duration of your contract.

6The energy

  1. The electricity the node consumes is the host's, consumed by equipment belonging to the host on the host's premises. The host does not sell energy to SolarGPU or to third parties, and SolarGPU neither buys nor resells it.
  2. The kilowatt-hour is the unit of measure of the rent of the lease, not the object of a sale.
  3. The host holds their own electricity supply contract and, if they have one, their self-consumption installation, and is responsible for the node being able to be powered from it.

Why. Self-consumption requires the energy to be for your own use. Your own node, in your home, consuming your surplus, complies; selling that energy to a third party does not. This clause puts the boundary in writing, and it is the same one that keeps you from being a "producer" for tax purposes.

7Invoices, VAT and withholding

  1. Self-billing. The host authorises SolarGPU to issue the rent invoices in the name and on behalf of the host (art. 5 of the Invoicing Regulation, Royal Decree 1619/2012). This contract is the prior agreement the regulation requires; each invoice is subject to the host's acceptance in the app and is not paid until accepted. The host can reject an invoice stating the reason, and it is corrected.
  2. VAT. The rent carries the applicable VAT (currently 21 %). SolarGPU pays it to the host together with the rent and the host pays it in on their quarterly return.
  3. Withholding. SolarGPU applies the applicable personal income tax withholding (currently 19 %) to hosts who are private individuals, pays it in to the tax authority competent for the node's location and delivers the annual certificate. If the host is a company and declares that the lease is part of its business activity, no withholding is applied.
  4. VAT returns. SolarGPU prepares the draft of the host's quarterly returns (Form 303) and annual summary (Form 390) from the invoices it issues, and files them if the host authorises it. The host remains the taxpayer and keeps the right to file them on their own.
  5. If the host's tax status changes (private individual, self-employed, company), invoicing is adjusted from the month following notification.

Why. This is what makes "zero work" true with the Tax Agency too: the law allows the invoice to be issued by the payer, and the only obligation you are left with — the VAT return — reaches you ready-made. Details and figures in Taxation, points 2 to 4.

8Referrals

  1. For every host who joins on the host's referral and keeps their node active, the host's rate goes up €0.01/kWh, up to the cap published for their class (for example, from €0.35 to €0.44/kWh on an SG1 with nine referrals).
  2. The increase applies from the month after the referred node is activated and remains as long as that node is under contract.

9Term and end of the contract

  1. One year from the node's activation, renewable year by year unless either party gives notice otherwise.
  2. No lock-in. The host can end the contract at any time with 30 days' notice, without penalty. SolarGPU can do so with 30 days' notice, or immediately if the node is used contrary to clause 4.2 or is tampered with.
  3. On termination, SolarGPU remotely erases its software and the customers' data, leaves the node in a clean, documented state, and settles the last rent. The node remains the host's, with no obligation to return it, sell it or keep leasing it.
  4. The host can sell the node; the buyer may sign a new contract. If the host stops leasing it and puts it to private use, they must regularise the VAT they deducted, as explained in Taxation, point 4.

Why. "The equipment is yours" has to be true on the way out, not just on the way in. Being able to leave at no cost is what protects you if the compute market changes; the contract year is what guarantees your rate.

10Warranty and breakdowns

  1. The node's warranty is that of the purchase contract, separate from this one: three years of statutory warranty if you bought it as a consumer, under the Spanish General Consumer Protection Act, and the manufacturer's warranty in any case.
  2. If the node breaks down, SolarGPU diagnoses it remotely, handles the repair or replacement with the manufacturer or the seller and organises collection and delivery. While the node is not working there is no rent, and neither party owes the other anything for that time.
  3. Normal wear from the node's use is borne by the host, as owner, and is what tax depreciation compensates for. Damage caused by SolarGPU's software or operation is borne by SolarGPU.

11Liability

  1. SolarGPU is liable for the node's operation, for the relationship with customers and for the use they make of the compute: it will hold the host harmless against any third-party claim arising from that use.
  2. The host is liable for their electrical installation, their home network and the obligations in clause 4.
  3. Neither party is liable to the other for loss of profit: SolarGPU does not guarantee the host a minimum rent, and the host does not guarantee SolarGPU availability.
  4. Neither party is liable for what a case of force majeure prevents, including power or network outages beyond their control.

12Data and security

  1. SolarGPU processes the host's data (identity, tax ID, node address, bank account, consumption and hours of use of the node) to perform this contract and meet its tax obligations, and keeps it for the duration of the contract and the subsequent statutory periods. The host's rights are exercised at hola@solargpu.es; the full policy is at Privacy.
  2. The data of SolarGPU's customers that passes through the node is SolarGPU's responsibility; the host has no access to it and no obligation regarding it.
  3. SolarGPU applies to the node the security measures described in clause 3.2 and notifies the host of any incident affecting them.

13Assignment of the contract

SolarGPU may assign the contract to a company in its group that takes over the operation of the nodes, notifying the host and without any term changing. The host may only assign it together with ownership of the node (clause 9.4).

14Applicable law and changes

  1. Spanish law. If the host is a consumer, the courts of their domicile; if a company or professional, those of Vitoria-Gasteiz.
  2. The terms of the signed contract do not change during its term. New versions of this text are published at this address with their date and apply to new contracts and renewals, with the same 30 days' notice as in clause 5.2.

Version 1.0, 16 September 2026. We will publish changes at this same address with their date. Questions: hola@solargpu.es.