Phoenix induction boiler for central heating and hot water + photovoltaic

I had a sas of 27 kw with a feeder
Lightly 10 - 12 tons went per season ...
I was heating mostly without a basement ...

Even if I get a thousand a month, I will be happy ...

As for the buffer, I think it will cover these few hours without reheating ..
There will be no heating between 7:00 and 13:00, i.e. 5 hours, and between 16 and 21 also 5 hours.
The rest at the lowest tariff ..

As for the plumbers. Most did not know what an induction furnace or an electrode furnace was.

As for water and ecectrolysis. The water should not be replaced once a year.

As for electric heaters.
I had heaters in the boiler every few years, even the best ones.


As for the ecectrolysis

In those people who have electrode furnaces, I have not heard that there is a problem with the pipes.

It is a bit similar to gas in a car. We all know that gas destroys the engine etc. I have been driving on gas for 20 years and every car I have installed returns after a few months and nothing happened to the engines.

Tom2349 wrote:

I had a sas of 27 kw with a feeder
Lightly 10 - 12 tons went per season ...
I was heating mostly without a basement ...

And here comes the basement

Tom2349 wrote:

Even if I get a thousand a month, I will be happy ...

But you are naive.
Let's count, because we already have some data.
Let's take an average of 11 tons of coal with a calorific value of 22MJ / kg. I count the weakest coal that can still be burned in the feed boiler. If I took into account better coal, the calculations would be even more pessimistic.

11,000 kg of coal x 22MJ = 242,000MJ = 242GJ of energy
242GJ = approx. 67222.2kWh
You got that much energy from burning 11 tons of coal.
Assuming the real efficiency of a coal-fired boiler at 50%, this gives us the result of approximately 33611kWh. You needed that much energy to keep your home warm.
1kWh in the first tariff costs about PLN 0.65
1kWh in the 2nd tariff costs about PLN 0.3.
To get 33611kWh of electricity in the first tariff you will have to spend about PLN 21847
To obtain 33611kWh of electricity in the 2nd tariff, about PLN 10,083

Tom2349 wrote:

As for the buffer, I think it will cover these few hours without reheating ..
There will be no heating between 7:00 and 13:00, i.e. 5 hours, and between 16 and 21 also 5 hours.
The rest at the lowest tariff ..

Oh .... vain hopes
So let's count.
An insulated house with an area of 450 m2 will need about 25kW of heating power at -20'C to keep it inside + 20'C.

You have a 1000 liter buffer and convection heaters that need water at a temperature of not less than 50'C to heat.
The lowest useful temperature of the buffer must not be less than 50 ° C.
Assuming that it will heat the buffer up to 100'C, you will increase the water temperature in the buffer by a maximum of 50'C.
So let's count how much energy you can store in such a buffer:
4.2kJ x 50'C x 1000 liters = 210000kJ = 210MJ
210MJ = approx. 58.34kWh
So you will accumulate energy for 2 hours of heating in the first tariff. So you will have to heat up for 6 hours in the first tariff.

This buffer will only be sufficient for you only when the outside temperature does not drop below 7-8'C.
At lower temperatures, you will have to heat the house in tariff 1, and here the costs are rising.

So as you can see, it does not look optimistic. I think you burned a bit better coal, i.e. with a calorific value closer to 24-25MJ / kg, and the actual boiler efficiency could have been slightly higher.

Tom2349 wrote:

As for the plumbers. Most did not know what an induction furnace or an electrode furnace was.

And those who know well what an induction and electrode furnace are, you don't want to listen.

Tom2349 wrote:

As for water and ecectrolysis. The water should not be replaced once a year.

How many times a year you will have to change the water depends on the quality of the water you fill the system with.

Tom2349 wrote:

As for electric heaters.
I had heaters in the boiler every few years, even the best ones.

Well, look, and I often replaced heaters that worked for over 10 years and a boiler used every day.

Tom2349 wrote:

As for the ecectrolysis
In those people who have electrode furnaces, I have not heard that there is a problem with the pipes.

And how many of these people have been heating with such a boiler for several years?

Tom2349 wrote:

It is a bit similar to gas in a car. We all know that gas destroys the engine etc. I have been driving on gas for 20 years and every car I have installed returns after a few months and nothing happened to the engines.

And I experienced burnout of the valves in the engine in my wife's car, which caused the car to catch fire because the gas started to shoot and damaged the air intake pipe. The car caught fire and if it weren't for the help and quick reaction of the TIR driver who put out the car with his large fire extinguishers, the car would have completely burned down. Before the intervention of the truck driver, accidental drivers gave their 3 fire extinguishers + 2 extinguishers from my wife's car without even making an impression on the fire. If not for the large fire extinguishers from the TIR, the car would burn completely. Since then, I have not been gassing cars and buying gassed ones. Previously, I was a huge supporter of gas, but after this event I am already a skeptic, especially since I calculated it completely does not pay off for me, because I use several cars. It would make sense if I were to do long tours. But it happens that I drive 3 cars in turns during the day.

In sum:
We have approx. 7 heating months.
On average, it is about PLN 1,500 for each month. in the coldest months you will have bills of PLN 2000-2500 per month. Assuming you can only heat on tariff II.

Added after 46 [minutes]:

PS
Forget about photovoltaics with such a heating system.
1kW of photovoltaics produces approximately 0.95MWh of energy annually.
You need over 67 MWh of energy to heat your home.

In the case of a photovoltaic installation, you can only get 70% of the energy from the grid, because the installation would have to have over 10kW of power.
So theoretically, in order to get your electricity to heat this house, you would have to have a photovoltaic installation with a capacity of over 100kW.
The problem is that you can only be a prosumer if your installation does not exceed 50kW.

Therefore, we are building a 50kW installation that will cover half of your electricity needs.
You still have to buy energy for PLN 5,000 a year minimum and spend 150-200,000 PLN. PLN for photovoltaics.

By switching to an air heat pump, you spend approx. 50 thousand. zloty. and you pay about 3500 thousand for heating. PLN per year.
In addition, you can also arrange air conditioning for the summer, because the pump can heat up in winter and cool in summer.

Plumpi wrote:

11,000 kg of coal x 22MJ = 242,000MJ = 242GJ of energy
242GJ = approx. 67222.2kWh
You got that much energy from burning 11 tons of coal.
Assuming the real efficiency of a coal-fired boiler at 50%, this gives us the result of approximately 33611kWh. You needed that much energy to keep your home warm.

Suppose there is DHW energy in this and let it consume 3000 kWh per year for this purpose.
33,611-3,000 = 30,611 kWh per year for central heating purposes
Taking into account 172 heating days according to heat, we actually have 178 kWh per day, i.e. the average, constant heating power is approx. 7.4 kW for the purposes of

With such assumptions, the bills of PLN 1000 / month for electricity due to the use of the boiler for the purposes of what is a beheaded dream.

Thank you for the calculations ..
I bought coal on average for PLN 900, always the best one ..

This week, I install meters for pumps and a stove. I'll have it all figured out.

At the moment, I have the mixing valves set to 40 degrees and at a temperature of minus 3 degrees outside I have 23 degrees at home.

And these calculations were made at a temperature of minus 3 even to minus 5 degrees.

I think a 5 hour buffer will be enough .. We'll see ..

It also installs temperature controllers so that the temperature during sleep is lower at night.

The most expensive fare is in the afternoon, and indirectly until noon.

The house was built in 2005 and I also have heating in the floor on the return ...

For what I have now.
At minus 5 degrees, heaters at 40 and at home 23 degrees.
And this is the most important thing ...

I still think that I will go below 1000 for heating ...
My house is well insulated and the furnace standstill times are getting longer every day.

In order for the condition to be met, on average, PLN 1,000 / month is the annual consumption for purposes, which would have to be below 20,000 kWh and provided that 100% of energy would be generated in the G12 night tariff, where 1kWh is the cost of approx. PLN 0.31 gross.

Added after 1 [minutes]:

Tom2349 wrote:

The most expensive fare is in the afternoon, and indirectly until noon.

I don't know what you get for the tariff, but in G12 the night rates are usually between 22-6 and 13-15, in the remaining hours 6-13 and 15-22 you have the daily rate approx.

Mid-morning peak 7 to 13
Afternoon peak 16 to 21
The remaining hours 1pm to 4pm and 9pm to 7pm

In the photo, no transmission or fixed charges

Tom2349 wrote:

For what I have now.
At minus 5 degrees, heaters at 40 and at home 23 degrees.
And this is the most important thing ...

only this is not due to the boiler, but to your central heating installation and its heating power.
The heating power of the radiators, i.e. their physical size, affects the heat output at a given temperature of the boiler water, and this in turn affects the final air temperatures that can be achieved in the rooms. Building thermal insulation influences the demand for thermal energy and the perception of thermal comfort.
The heat buffer makes a big difference here, because it provides a constant supply of hot water to the radiators, which means you have an effect similar to that of district heating and it certainly increases thermal comfort.
However, I do not see any advantage of your boiler over ordinary electric heaters, if you had them installed in the buffer.

Added after 7 [minutes]:

Tom2349 wrote:

Mid-morning peak 7 to 13
Afternoon peak 16 to 21
The remaining hours 1pm to 4pm and 9pm to 7pm

In the photo, no transmission or fixed charges

I do not know what you have for the tariff, because with me, if not G12, there is possibly a G12w to choose from, but there is also a split between the peak and off-peak, there are no 3 different rates.
Transmission fees are important because they are part of the final cost of 1kWh.
I ignore subscription fees, because you still need to have electricity in the hut, so they will not disappear, at most their rate may change depending on the selected tariff.

BUCKS wrote:

However, I do not see any advantage of your boiler over ordinary electric heaters, if you had them installed in the buffer.

Because you don't know each other. Electrode boilers in relation to the heater have 70-80% higher efficiency, because the heater has an efficiency of only 20-30% ;)

Here I propose to listen to the greatest authority in the world:
https://youtu.be/puRMeMpvV_8?t=155

Plumpi wrote:

Because you don't know each other.

You're right, I'm just an amateur who licked something about heating ;)

I have already seen this video from your link.
Thanks to reading this thread, I am already smarter and next year I will fire a gas boiler and buy an electrode boiler, I will pay PLN 250 / month

By the way, I warn against "free soups".

In my family, a young couple was seduced by an offer from one of the companies. They offered very cheap electricity, and at night, at certain times, even for free. For the heating season of the house, they only paid PLN 1,500 or PLN 1,600, including electricity consumption for household purposes.
They were even persuaded to use ordinary resistance heating mats instead of traditional water-circulating floor tiles, because allegedly the installation would be much cheaper.
Now they are in black ****, because the "free soup" ended after a year, and now they have to overpay for electricity and bullion for almost 10,000 zlotys. PLN for the heating season. The problem is that the mats do not heat up the floor like water pipes and the heating has to work both at night and during the day. A small house, not even 150m2
In addition, they have a child with allergies at home and unfortunately, a built-in fireplace can only be a decoration. For the same reason, they cannot install air conditioners. For obvious reasons, peeling off all floors and building a normal water-based underfloor heating system is out of the question.

The in-laws have 10kWp solar farm. They wanted to eliminate smoke and burn electricity. Some smart fitter pressed an induction furnace on them. They heat only during a transitional period, because in winter it was able to take 100kwh in one day. Large house, 10 cm double-glazed polystyrene. But my father-in-law still claims that this stove is more economical than the heater in the boiler (which also has one). But what can I know, I am not a marketer, but an Electrical Engineering engineer ? and a woman, so I certainly wanted to wrongly explain to them that this is not a good solution.

Before changing the heating, it is worth calculating the heat demand of the building. When I perform thermal modernization audits, I use Arcadia termocad for this program, there is also a RES auditor or something like that, you can download the demo version and calculate the demand and then no installer will press anything for you.

House from 2000, Podlaskie Voivodeship, heated 200m, including about 90m floor heating. The temperatures are around 30 degrees C on the floor and 42-48 on the radiators. The first season of PC heating with an 8kW air-conditioning system. At home, 22st. C energy consumption is XI-2300kWh, XII-3300kWh, I-4300kWh, II-4000kWh, a total of 13900kWh. It was about twice as expensive as coal, not including the photovoltaics I have (9.5Kw)

Somehow I am not convinced by this induction stove, especially the price, apart from its durability. Somehow, I do not believe that the failure rate of this induction (a lot of high-power electronics vs a simple thermostat with a heater) will be smaller than a tank with a decent titanium anode and a heater, and the price is not comparable (PLN 11 vs PLN 2), we also have a hot water buffer. This heat buffer in the form of water can be distributed by the automatics of the furnace (e.g. oil, pellets, peas) by sucking it through the heat exchanger (coil or water jacket) of the reservoir and transferring it to the existing central heating installation using water for heat transport. At the reservoir, e.g. with a 200l tank and cooling the water by 20C (say from 60C to 40C), we have 4.65kWh of heat, e.g. to heat the house in the morning, before the sun starts working. Of course, it can be, for example, 9.3 kWh when cooled by 40C (e.g. from 80C to 40C) or more at a higher temperature, or a larger tank capacity. Of course, a heat pump is better, especially when someone decides to make a stupid (in my opinion) investment in an induction furnace. after all, 10-15 thousand more and we have a heat pump.

zedg wrote:

The first season of PC heating with an 8kW air-conditioning system. At home, 22st. C, energy consumption is XI-2300kWh, XII-3300kWh, I-4300kWh, II-4000kWh, total 13900kWh

Either you have a poorly insulated house, or your PC has poor parameters, because you have spent a lot of money on heating. The fact that you live in the coldest climate zone also explains a bit.

January, February after several days of temperature -15 -25 ° C, a few days with the booster heater on. And, of course, DHW heating for six people.

Here, it would be better for you to go out by installing a gas boiler with your tank.