Technik sleduje spotřebu energie.

Because it is the direct object of the verb sleduje.

The basic dictionary form is spotřeba = consumption.
In the sentence, the technician is monitoring the consumption, so Czech puts spotřeba into the accusative singular:

• spotřeba = nominative
• spotřebu = accusative

This is a very common pattern for feminine nouns ending in -a.

Here, energie is in the genitive singular, because it depends on spotřeba.

So the structure is:

• spotřeba energie = consumption of energy

In English, we use of. In Czech, that relationship is often shown by the genitive case instead.

So:

• spotřeba = consumption
• energie = of energy

That is why the sentence has spotřebu energie, not spotřebu energii.

Sleduje is the 3rd person singular present tense form of sledovat.

The subject is technik, which is singular, so the verb must also be singular:

• já sleduji / sleduju = I monitor
• ty sleduješ = you monitor
• on/ona sleduje = he/she monitors

So Technik sleduje... means The technician monitors...

Not literally in the physical sense. In this sentence, sledovat means something like:

• monitor
• track
• observe

So Technik sleduje spotřebu energie is more like The technician monitors energy consumption than The technician follows energy consumption.

Czech sledovat can sometimes correspond to English follow, but in technical contexts monitor or track is often the best translation.

Because Czech has no articles.

English needs words like a, an, and the, but Czech normally does not use anything equivalent. Whether the meaning is definite or indefinite is understood from context.

So Technik can mean:

• a technician
• the technician

And spotřebu energie can mean:

• energy consumption
• the energy consumption

The context tells you which is meant.

Yes. Czech word order is more flexible than English word order because the case endings help show what each word is doing.

The neutral order here is:

• Technik sleduje spotřebu energie.

But you could also say:

• Spotřebu energie sleduje technik.

That would put more emphasis on spotřebu energie.

Even when the order changes, the endings still show that:

• technik is the subject
• spotřebu is the object

Grammatically, technik is a masculine noun. It usually refers to a male technician.

For a female technician, Czech commonly uses:

• technička

So:

• Technik sleduje spotřebu energie. = a male technician is monitoring energy consumption
• Technička sleduje spotřebu energie. = a female technician is monitoring energy consumption

In the present tense, the verb sleduje itself does not show gender.

A rough pronunciation guide is:

TECH-neek SLE-du-ye SPOT-rzhe-bu E-ner-gi-ye

A few important points:

• Czech stress is usually on the first syllable of each word.
• ch in technik is not English ch; it is the throaty sound heard in German Bach or Scottish loch.
• je in sleduje sounds roughly like ye.
• ř in spotřebu is a special Czech sound; English does not really have it. At first, an approximate rzh is fine.

It is a very common collocation, especially in technical, environmental, and business contexts.

It simply means:

• energy consumption

You will also see similar phrases such as:

• spotřeba elektřiny = electricity consumption
• spotřeba plynu = gas consumption
• spotřeba vody = water consumption

So yes, this is a very natural and common Czech phrase.

Grammatically, yes, but it would mean something different.

• Technik sleduje spotřebu energie. = The technician monitors energy consumption
• Technik sleduje energii. = The technician monitors energy

The second sentence is much less specific and may sound odd in many contexts. In your original sentence, the focus is not on energy itself, but on how much energy is being consumed. That is why spotřebu energie is the natural expression.