Netselskabet undersøger strømafbrydelsen.

Because -et is the definite article attached to the noun.

In Danish, instead of usually saying the as a separate word, you often add the definite ending to the noun:

• et netselskab = a network company / a grid company
• netselskabet = the network company / the grid company

So Netselskabet means the grid company.

This is very common in Danish:

• et hus → huset = the house
• en bil → bilen = the car

Here, netselskab is a neuter noun, so its definite ending is -et.

Because Danish usually puts the at the end of the noun.

So instead of:

• the company

Danish often says:

• selskabet

And instead of:

• the outage

Danish says:

• afbrydelsen

This is one of the biggest differences from English. The definite article is often a suffix:

• en afbrydelse = an interruption
• afbrydelsen = the interruption

A separate definite word such as den/det is used in some other structures, especially with adjectives:

• strømafbrydelsen = the power outage
• den alvorlige strømafbrydelse = the serious power outage

Yes. Danish very often combines nouns into one compound word.

Netselskabet is built from:

• net = network/grid
• selskab = company
• -et = the

So:

• netselskab = network company / grid company
• netselskabet = the network company / the grid company

This happens all the time in Danish:

• togstation = train station
• mobiltelefon = mobile phone
• elselskab = electricity company

A good rule: if English uses several nouns together, Danish often writes them as one word.

Undersøger is present tense.

The infinitive is:

• at undersøge = to investigate / to examine

The present tense is:

• undersøger = investigates / is investigating

So the sentence can mean:

• The grid company investigates the power outage or, more naturally in English,
• The grid company is investigating the power outage

Danish present tense often covers both:

• simple present
• present continuous

That is normal.

Because many Danish verbs form the present tense with -er.

For at undersøge:

• infinitive: undersøge
• present: undersøger

Other examples:

• at arbejde → arbejder
• at købe → køber
• at undersøge → undersøger

Also, Danish verbs do not change according to person the way English sometimes does. So the same present form is used with all subjects:

• jeg undersøger = I investigate
• du undersøger = you investigate
• han undersøger = he investigates
• de undersøger = they investigate

It is another compound noun.

It can be broken down like this:

• strøm = electricity / power / current
• afbrydelse = interruption
• -n / -en = the

So:

• strømafbrydelse = power outage / power cut
• strømafbrydelsen = the power outage

Literally, it is something like the electricity interruption.

This kind of compound-building is extremely common in Danish, so it is useful to train yourself to spot the parts inside long words.

Because Danish nouns have different grammatical genders.

There are two genders in modern Danish:

• common gender → usually takes en in the indefinite form and -en in the definite form
• neuter gender → usually takes et in the indefinite form and -et in the definite form

So:

• et netselskab → netselskabet
• en afbrydelse → afbrydelsen

You have to learn the gender of each noun together with the noun itself.

A very useful habit is to memorize nouns with their article:

• et selskab
• en afbrydelse
• en strøm
• et net

No, this is the normal main clause word order in Danish:

Subject + verb + object

• Netselskabet = subject
• undersøger = verb
• strømafbrydelsen = object

So it matches basic English order:

• The grid company
  • is investigating
    • the power outage

Danish often follows this pattern in simple statements.

The main thing to remember is that Danish is a V2 language, which means the finite verb normally comes in the second position in main clauses. In this sentence, the subject comes first, so the verb naturally comes second.

Yes. At undersøge is a broad verb.

Depending on context, it can mean:

• investigate
• examine
• look into
• inspect

In this sentence, investigating or looking into is probably the most natural English choice, but examining is not wrong in a broader sense.

Because in Danish, compounds are normally written as one word, not as separate words.

So Danish writes:

• netselskab
• strømafbrydelse

not:

• net selskab
• strøm afbrydelse

Writing them as two words would usually look wrong to a Danish reader, or it could change the meaning.

This is a very common spelling issue for learners, especially English speakers, because English often uses separate words where Danish uses compounds.

Not in this context.

Although net can mean net or network in different contexts, here netselskab usually refers to a company that operates the electricity grid.

So in this sentence, Netselskabet is best understood as:

• the grid company
• the utility network company
• sometimes simply the utility company, depending on context

Because the sentence also contains strømafbrydelsen (the power outage), the electricity-grid meaning is the obvious one.

It would be:

• Et netselskab undersøger en strømafbrydelse.

That means:

• A grid company is investigating a power outage.

Compare the forms:

• et netselskab = a grid company

• netselskabet = the grid company

• en strømafbrydelse = a power outage
• strømafbrydelsen = the power outage

This is a good way to see how Danish moves between indefinite and definite forms.

No. Danish does not capitalize all nouns.

So:

• netselskabet
• strømafbrydelsen

are normally written with lowercase letters.

In your sentence, Netselskabet has a capital N only because it is the first word of the sentence, not because it is a noun.