Samoopskrba smanjuje višak električne energije.

Samoopskrba literally means self-supply or self-sufficiency. In an energy context, it often refers to producing and using your own energy, for example from solar panels.

It is built from:

• samo- = self-
• opskrba = supply

Grammatically, it is a feminine singular noun here, in the nominative, because it is the subject of the sentence.

Smanjuje means reduces / is reducing.

It is:

• 3rd person singular
• present tense
• from the imperfective verb family related to smanjivati

It matches samoopskrba, which is singular, so Croatian uses singular verb agreement:

• samoopskrba smanjuje = self-supply reduces

This present tense is the natural choice for a general statement or ongoing effect, like English reduces.

Because višak is a masculine inanimate noun, and in Croatian many masculine inanimate nouns have the same form in the nominative and accusative singular.

So here:

• samoopskrba = subject
• višak = direct object

Even though višak looks unchanged, its role is clear from the sentence structure and meaning.

Because višak normally takes a genitive complement in Croatian.

So the structure is:

• višak = surplus / excess
• električne energije = of electrical energy

This is the same idea as English an excess of electrical energy.

So:

• višak električne energije = surplus of electrical energy

You are not directly describing višak with an adjective here. Instead, energije tells you what the surplus consists of.

Because both words are in the genitive singular feminine:

• energija → energije
• električna → električne

The adjective has to agree with the noun in:

• gender
• number
• case

Since energija is feminine singular and appears in the genitive after višak, the adjective also becomes električne.

Because energija is being used as a mass noun, like energy in English.

Croatian normally treats electrical energy as a single substance/concept, so the singular is natural:

• električna energija = electrical energy
• višak električne energije = a surplus of electrical energy

Using the plural would usually sound unnatural here unless you were talking about different types of energies in a special scientific context.

Yes. Croatian word order is fairly flexible because case endings show grammatical relationships.

This sentence uses a very neutral order:

• Samoopskrba smanjuje višak električne energije.
• subject + verb + object

You could also say:

• Višak električne energije smanjuje samoopskrba.

That would put more emphasis on višak električne energije. It is still understandable, but the original version sounds more neutral and standard.

Because Croatian has no articles.

So a noun like višak can mean:

• a surplus
• the surplus
• just surplus in a general sense

The exact meaning depends on context. In this sentence, English may need the or no article depending on the wider situation, but Croatian does not mark that with a separate word.

Usually reduces.

Croatian present tense often covers both:

• a general truth: Self-supply reduces surplus electrical energy
• an ongoing process: Self-supply is reducing surplus electrical energy

Without extra context, the sentence most naturally sounds like a general statement or regular effect, so English reduces is usually the best match.

A helpful breakdown is:

• sa-mo-op-skr-ba

A few tips:

• pronounce every vowel clearly
• oo is not one long English vowel; it is really o + o
• pskr is a consonant cluster, so say it carefully and steadily

A rough English-friendly guide would be:

• sa-mo-op-skr-ba

The spelling is quite phonetic, so once you know the sounds, Croatian pronunciation is usually straightforward.