Which Generator for a Home & Heat Pump? Inverter vs Portable vs Stationary

Every day we receive a few emails with this (or a very similar) question:

"Good morning, I want to buy a generator to use in emergency situations to power, for example, a freezer, a heat pump, a deep-well pump, and to charge flashlights, a radio and a phone. A crisis generator — solid equipment that won’t let me down and will last for years. Three-phase. I live in a detached house in the countryside and I’m self-sufficient. I need equipment that, if necessary, during blackouts, will get the job done. I want everything to work automatically. I think around 10 kW should be enough. I forgot to add that the induction hob must work as well. Which generator should I buy and how much money do I need to allocate for it? Thank you for your reply. Kind regards."

This time we will be very specific. Review the table and see what types of generators you can buy, what power ranges each type offers, and roughly how much each type of generator costs.
Below the table you’ll find a QUICK CONCLUSION explaining why it is THIS way and not otherwise, and what the real purpose is of the generators we are discussing today.
One more quick explanation: in the table we use commonly used, everyday terms for different machine types:

- INVERTER - generators built using inverter technology.
- PORTABLE - open-frame portable generators (traditional units in a steel frame).
- STATIONARY - generator sets intended for professional outdoor operation as stationary applications.
- QUESTIONABLE QUALITY - units that are easy to confuse with portable generators; low-end Far East products that represent nothing but problems and hassle.

Responsive table with sticky header

WHICH GENERATOR SHOULD YOU CHOOSE TO POWER A HOME, OFFICE OR A MODERN BUILDING?
DISADVANTAGES, ADVANTAGES AND PRICES OF EACH SOLUTION.
TYPE OF GENERATOR USED	ADVANTAGES OF THIS SOLUTION	DISADVANTAGES OF THIS SOLUTION
	ADVANTAGES OF INVERTER GENERATORS Very stable “230 V” voltage Clean sine wave “~” Accurate frequency “50 Hz” Low THD Compact enclosure Very quiet operation Affordable price Often USB outlets as standard Often 12 VDC outlets as standard Often parallel operation (sync) of 2 generators Often a display showing operating parameters PRICE RANGE From PLN 2,600 to PLN 12,000 (gross) AVAILABLE POWER OUTPUT From 1 kW to 8 kW	DISADVANTAGES OF INVERTER GENERATORS No three-phase “400 V” units Limited resistance to weather conditions We do not recommend them for ATS / automatic transfer switch
	ADVANTAGES OF “PORTABLE” GENERATORS Low prices Sturdy frame Simple design Available in single- and three-phase (230 V / 400 V) Wide choice of power ratings and configurations PRICE RANGE From PLN 3,000 to PLN 25,000 (gross) AVAILABLE POWER OUTPUT From 2 kW to 15 kW	DISADVANTAGES OF “PORTABLE” GENERATORS Despite AVR, frequent voltage fluctuations Frequency fluctuations (Hz) Loud operation Usually high THD Limited resistance to weather conditions We do not recommend them for ATS / automatic transfer switch
	ADVANTAGES OF “STATIONARY” GENERATORS Designed to work with ATS / automatic transfer switch Manual or automatic operation Stable power supply parameters Diesel engines at 1500 RPM High-quality alternators Low fuel consumption Continuous operation possible – 24/7 Large fuel tanks Quiet operation – well soundproofed enclosures Works in all weather conditions Unlimited choice of power output Long-term investment PRICE RANGE From PLN 40,000 (gross) AVAILABLE POWER OUTPUT From 7 kW and above (no upper limit)	DISADVANTAGES OF “STATIONARY” GENERATORS High price Large size
	ADVANTAGES OF “QUESTIONABLE QUALITY” GENERATORS NONE PRICE RANGE From PLN 300 (gross)	DISADVANTAGES OF “QUESTIONABLE QUALITY” GENERATORS Very large voltage fluctuations Very unstable frequency (Hz) Very loud Very high THD Limited resistance to weather conditions Falsified technical data Counterfeit certificates Very poor build quality Unreliable engines Unreliable alternators No service and no spare parts No warranty No quality

- Quick conclusion about what’s in the table -

If we are talking about a modern home / office (heat pump, automation, electronics, servers, router, induction hob), then stable power supply parameters are crucial, and for convenience, the ability to operate automatically. And this is the simple truth: not every “10 kW” works the same — what matters is voltage quality, frequency stability, and whether the generator is truly ready to cooperate with an ATS. That’s why we share our knowledge and experience—so you can tell what is true and what is not.

- INVERTER GENERATORS -

Best for electronics and “sensitive” loads, very good as backup power. They deliver very stable 230 V, a clean sine wave, 50 Hz and low THD, and they are usually quiet and convenient. The downside: virtually no 400 V, limited outdoor toughness, and—importantly— we do not recommend them for ATS, so for full-house automation it is usually not the right choice. Ask yourself if you really need “three-phase” 400 V. Most often customers want to power a “three-phase heat pump”. If it is truly three-phase 400 V, an inverter won’t work. If it is a small single-phase 230 V heat pump, the most powerful inverter models can handle it.

Can you power an induction hob? Yes, because truly three-phase induction hobs are rare; most are single-phase units that are wired across two or three phases. Therefore, the most powerful inverters can also be connected for induction cooking. Using ATS with these machines doesn’t really make sense; however, a manual GENERATOR / GRID changeover switch is a practical solution.

In our opinion, inverter generators are the best choice for emergency power for a small home or office in a crisis or blackout. They also work great on a camping trip or with a camper van :) Good choice for very reasonable money.

- PORTABLE GENERATORS -

They tempt with price and power, but it’s a compromise in power quality. The advantages are low price, simple design, availability of 230/400 V (single- and three-phase) and a wide power selection. The downsides in a modern building are serious. Even with AVR (or capacitor regulation), they can have voltage and frequency fluctuations, so whether sensitive electronics will work properly can be a lottery. You won’t know until you connect and test. They can be loud.

We do not recommend connecting this type of generator to ATS. It’s not what they are designed for and it will not work properly. It is possible and some people recommend it—our answer is no. If you have bought or plan to buy such a generator for your home, connect it via a manual GENERATOR / GRID changeover switch.

Open-frame portable generators are ideal as construction generators, for heavy-duty work, and for field power where there is no mains supply and you need electricity at low cost. This does not change the fact that these are currently the most commonly purchased generators for powering homes and small households in Poland. This is because for a reasonable price they offer high power and three-phase voltage. Also, there is a solid selection of good generators in this class in Poland, and everything we offer in our store are the best designs available in Poland in one place.

Do we recommend them? YES — very much, but mainly for what they are meant for: everyday work on construction sites, portable power, and broadly understood “heavy daily work...”.

Now a concrete question and answer, because the main argument for choosing this type of generator is usually: it must run a heat pump.
Is this type of generator suitable for powering a HEAT PUMP?
YES, it is suitable, but the condition is correct and reliable generator operation. In 90% of cases in this class, correct operation depends on a properly running engine. These generators always use alternators designed for 3000 RPM. If the engine maintains speed in the correct range, voltage and frequency will be within limits. If the engine runs too fast — frequency increases; too slow — frequency decreases. This can be dangerous for powered devices.

That is why the condition for powering heat pumps and electronic devices is a well-maintained generator and, most importantly, a well-serviced engine that maintains proper speed and power, which results in proper voltage parameters and frequency that safely power sensitive loads.

Finally, why don’t we recommend installing ATS on this type of generator? One of the key reasons is that the user should walk up to the generator and start it with the key. This gives at least some control and supervision: did it start, are the RPM correct, is there fuel, are voltages correct or too low/high? After confirming everything is OK, we switch the house over and we have power. Use it wisely, control and check if it works properly, and it will power sensitive devices for a long time without failures. If we leave the unit unattended (which ATS encourages), there is a high chance we will create problems.

- STATIONARY GENERATORS -

These are diesel generator sets with engines running at a constant speed of 1500 RPM. The only sensible solution when the goal is: “The house should operate normally and ATS automation should work properly.” Equipment designed for stationary operation: stable parameters, high-quality alternators, sensible fuel economy, operation in all weather conditions—and most importantly—full ATS compatibility and the ability to operate automatically and continuously (24/7). The downside is price and size, but in return you get a “long-term” solution that truly handles a modern building and gives you comfort with the highest probability that everything will work exactly when you need it. It’s professional and we know it is expensive, but if you can afford it and have enough space and installation options, there is no debate: it’s the best choice.

- QUESTIONABLE QUALITY GENERATORS -

Well, if you’ve made it this far and still plan to buy this type of generator, I still won’t convince you it’s not worth it :) It’s worth finding out for yourself :)