La puissance souscrite change le tarif.

In French utility or electricity-contract language, puissance souscrite is a fixed, technical expression. It means the contracted power level in your plan, not just power in a general sense.

So puissance alone is a broad word, but puissance souscrite points to a specific thing in an energy contract.

• puissance = power / capacity
• souscrite = subscribed / contracted

In everyday French outside this context, a learner would not usually guess this exact meaning just from the literal words, so it is worth learning as a set phrase.

In French, adjectives often come after the noun, especially when they are more descriptive, technical, or derived from past participles.

Here, souscrite is the past participle of souscrire, used like an adjective:

• puissance = noun
• souscrite = adjective-like past participle describing that noun

So French naturally says:

• la puissance souscrite

rather than putting souscrite before the noun.

Because puissance is a feminine singular noun.

When a past participle is used adjectivally in French, it agrees with the noun it describes:

• masculine singular: souscrit
• feminine singular: souscrite
• masculine plural: souscrits
• feminine plural: souscrites

Since puissance is feminine singular, the correct form is souscrite.

Change is the third-person singular present form of changer.

The subject is La puissance souscrite, which is singular, so the verb must also be singular:

• la puissance souscrite change

This is just the normal present tense, often used in French for general facts, rules, or statements.

In this sentence, change can feel broader than the English verb changes.

Depending on context, French changer can mean:

• to change
• to modify
• to alter
• to affect

In an energy or billing context, La puissance souscrite change le tarif means that the contracted power level changes/affects the tariff. So even if the literal translation uses changes, the practical idea is often closer to determines or influences.

Because tarif is the direct object of the verb changer here.

French commonly uses changer quelque chose for to change something:

• changer le tarif
• changer le prix
• changer la date

So there is no preposition here.

If you said changer de tarif, that would mean something different: to switch tariff / move to another tariff. That is not the same structure or meaning.

French uses definite articles more often than English does.

Here, le tarif refers to the relevant tariff in the situation being discussed, such as the tariff on an electricity contract. French often uses le / la / les where English might say:

• the tariff
• your tariff
• or sometimes just a bare noun, depending on context

So le tarif sounds normal and natural in French.

It is natural, but it sounds a bit technical or administrative. You are likely to see it in:

• electricity or energy contracts
• pricing explanations
• utility websites
• customer-service information

A native speaker would understand it, but it belongs more to the language of billing and contracts than casual conversation.

Yes, modifie is grammatically fine and may sound a little more explicit to an English speaker. However, change le tarif is also perfectly understandable.

That said, in real administrative French, you might also see alternatives like:

• La puissance souscrite influe sur le tarif
• La puissance souscrite a une incidence sur le tarif
• Le tarif dépend de la puissance souscrite

These can sound slightly more precise depending on the context.

A rough pronunciation guide is:

• puissance ≈ pwee-sahns
• souscrite ≈ soo-skreet

A bit more carefully:

• puissance: the ui sounds like a quick wee
• an in puissance is nasal
• souscrite ends with a pronounced t

So the whole phrase sounds roughly like:

la pwee-sahns soo-skreet

As always, the exact French sounds are not identical to English ones, but this approximation helps.