Ces panneaux solaires produisent de l'électricité même quand il fait froid.

French has different forms of “this/that / these/those” (demonstrative adjectives) that must agree in gender and number with the noun.

• ce – masculine singular before a consonant: ce panneau (this/that panel)
• cet – masculine singular before a vowel or mute h: cet homme
• cette – feminine singular: cette voiture
• ces – plural (masculine or feminine): ces panneaux (these/those panels)

In the sentence, you’re talking about more than one solar panel, so you must use the plural form:

• ces panneaux solaires = these/those solar panels

French has a spelling rule for nouns ending in -eau:

• Most nouns ending in -eau form the plural with -eaux, not -eaus.

Examples:

• un bateau → des bateaux (boats)
• un chapeau → des chapeaux (hats)
• un panneau → des panneaux (panels, signs)

The x is silent; you don’t pronounce it. The plural is heard mainly through context or the verb agreement (produisent).

In French, most adjectives come after the noun, unlike English.

• English: solar panels
• French: panneaux solaires

“solaire” here is an adjective meaning “solar” and must follow the noun panneaux.

Also, the adjective must agree in gender and number:

• un panneau solaire (singular, masculine)
• des panneaux solaires (plural, masculine → add -s)

So:

• panneaux solaires (correct)
• solaires panneaux (incorrect word order)

The verb produire (to produce) has to agree with the subject:

• Subject: Ces panneaux solaires → they, third person plural.
• Present tense of produire:
  
  • je produis
  • tu produis
  • il/elle/on produit
  • nous produisons
  • vous produisez
  • ils/elles produisent

So you need the third person plural form: produisent.

Note: the ending -ent is not pronounced; produit and produisent sound the same in normal speech. The difference is visible only in writing and through context (the plural subject).

There are two points here: the article type and the elision (l’).

1. Article type: “de l’” (partitive)
   French uses a partitive article (de + article) for indefinite uncountable things (like “some” electricity, water, bread):

• du (de + le): masculine singular before consonant
• de la: feminine singular before consonant
• de l’: before a vowel sound, masculine or feminine
• des: plural

Électricité is feminine and uncountable here, and it starts with a vowel sound, so:

• de + l’ → de l’électricité = “(some) electricity”

If you said l’électricité alone (with definite article la), it would mean “the electricity” in a more general or specific sense, not “they produce electricity” as a substance.

2. Elision: “de l’électricité” and not “de la électricité”
   Because électricité begins with a vowel sound, la contracts to l’:

• de la
  • électricité → de l’électricité

So “de l’électricité” is the grammatically normal way to say “(some) electricity” here.

You always need both parts: de + article (here, l’):

• de + le → du
• de + la → de la
• de + l’ → de l’
• de + les → des

Since électricité is feminine and starts with a vowel sound, the correct form of the article is l’:

• de + l’ = de l’électricité

Writing de électricité ignores the article, and d’électricité would usually come from de + électricité after elision of e (as in beaucoup d’électricité), but here we want the partitive article, so it must be de l’électricité.

The three expressions have different uses:

1. même quand = even when

   • Introduces a time or situation:
     
     • même quand il fait froid = even when it’s cold (out)
       This fits the idea: solar panels produce electricity even in the situations when it is cold.

2. même si = even if / even though

   • Introduces a condition or a concession:
     
     • même s’il fait froid, ils produisent de l’électricité
       = even if / even though it’s cold, they produce electricity.
       You could rewrite the sentence using même si, but the structure must change:
   • Ces panneaux solaires produisent de l’électricité même s’il fait froid.
     This is grammatical and very natural.

3. quand même = anyway / all the same / still

   • Usually appears after the verb or in a different position, not before quand:
     • Il fait froid, mais ils produisent quand même de l’électricité.
       = It’s cold, but they still produce electricity.

So “même quand il fait froid” is correct and natural for “even when it is cold.”

French uses a special set of expressions with faire to talk about weather:

• il fait froid = it’s cold (weather)
• il fait chaud = it’s hot
• il fait beau = it’s nice (weather)
• il fait mauvais = the weather is bad

Using être changes the meaning:

• il est froid – usually means he/it is cold in a personal or physical sense (e.g., a person or an object is cold in temperature or character).
• c’est froid – this/that is cold (pointing to a specific thing: the soup, the room, etc.)

When you talk about general weather, you almost always use il fait + adjective:

• il fait froid = it’s cold outside / as weather.

Here, “il” is an impersonal pronoun. It doesn’t refer to any person or object; it’s just required grammatically.

French often uses impersonal “il” in weather expressions and some fixed phrases:

• il pleut – it’s raining
• il neige – it’s snowing
• il fait froid – it’s cold
• il est tard – it’s late

In these cases, there is no real subject like “he” or “it” in English; “il” is just a placeholder so the verb can be conjugated.

Yes. lorsque and quand often mean the same thing: “when” (in the sense of “at the time when”).

So you can say:

• Ces panneaux solaires produisent de l’électricité même lorsqu’il fait froid.

It’s correct and a bit more formal or literary than quand. In everyday speech, quand is more common, but both are fine here.

Sentence: Ces panneaux solaires produisent de l’électricité même quand il fait froid.

Approximate pronunciation (using English-like hints):

• Ces → /se/ (like “seh”)
• panneaux → /pa-no/ (no x sound)
• solaires → /so-lɛr/ (final s is silent)
• produisent → /pro-dɥiz/ (final -ent silent)
• de l’électricité → /də le-lek-tri-si-te/ (the l’ is attached: de-le…)
• même → /mɛm/ (like “mem”)
• quand → /kɑ̃/ (final d silent, nasal vowel)
• il → /il/
• fait → /fɛ/ (final t silent)
• froid → /frwa/ (final d silent)

Spoken smoothly (with natural linking):
[se pa-no so-lɛr pro-dɥiz də le-lek-tri-si-te mɛm kɑ̃ til fɛ frwa].