For owners of private households who do not have the opportunity to carry out heating, an option such as combined heating for the home is suitable. With the help of this effective system, you can provide high-quality heating of the room and create a cozy home environment in it.
Scheme of combined heating of a private house
When purchasing a multi-fuel boiler design, which is an element of combined heating, you need to become familiar with the universal power of the boiler device. The area of the building and heating needs are also taken into account here. They consider the most effective and relevant heating combinations, which are based on three principles:
- energy is obtained from all kinds of known sources;
- energy is generated, saved and accumulated, followed by its rational use;
- the system is created both during the construction period and in the completed house.
Combined heating of a country house is a widely used type of heating, because it is very convenient to switch from one fuel to another by changing the burner included in the general set.
Combined heating option in a private house In this case, no significant changes occur in the settings; all issues are resolved using the instructions. There is one combustion chamber for two types of fuel, so the switching process is short-lived. Technically, this option is considered successful, despite the different fuel prices.
Originality of designs
Combination boilers They have several fireboxes for different types of fuel. In one of them, solid fuel is burned - wood and coal, in the other - liquid or gaseous fuel in the form of gas or diesel fuel. In such systems, it is possible to connect several autonomous lines and set different temperatures. For example, one supplies energy to the batteries, the other controls heated floors.
For heating two-story house- this is an excellent option, you just need to focus on the presence of separate heat exchangers, they are not available in every combination boiler.
Scheme of combined heating of a two-story house The latest developed representatives have built-in heating elements for working on existing energy carriers, and there are also burners that allow you to use both gas and diesel fuel by simply turning the switch to the desired mode. In order to save money and obtain the desired effect of heating a large area, it is worth using a heat accumulator; this is most relevant in boilers using coal. When using solid fuel, the power of the boiler system is not adjusted and the room becomes extremely hot. The heat accumulator present:
- removes excess heat and preserves it;
- with a lack of heat hot water transmitted to the DHW or system.
With this design, you can turn on the boiler less often.
Model selection
When starting to select boiler models, you need to know that the power level for certain types of fuel will be different.
House project with combined heating This is necessary to determine the main type used for heating purposes. One more information - in foreign boilers the rated power is indicated, and in Russian boilers the maximum power is indicated. This will give a significant difference in performance, so you need to be careful. Combination boilers for private homes have different capacities when changing fuel.
Cost of structures
Of course, when a boiler has a variety of fuel systems, it is more expensive and heavier. Only boilers combined with electric + wood are unchanged in size; the heating base is built into the boiler; it turns on automatically after the burner goes out and the temperature drops below the critical point.
Read also
Ventilation of the basement and cellar in the house
Scheme of combined heating using solar energy The cost of combined boilers with solid fuel + electricity is the same as for simply wood boilers - the changes are insignificant, and the size is almost the same, only a small heater is inserted. This design will help out if you don’t have the opportunity to regularly add firewood or don’t want to interrupt your night’s sleep.
One thing you just need to remember is that such electric boilers can only produce a third of the power, it won’t be possible to heat the house well, but it will help prevent the system from defrosting. A similar device has a coal + electricity composite boiler. You can put any solid fuel into it, just more often.
Types of combined heating systems
Gas + diesel boiler
The functioning and operation of this combination depends on the performance of the heat exchanger. Such a representative can be made of cast iron and steel separately or in combination. Consumers using a combination boiler for a private home have become convinced that with a gas pipeline located nearby, it is possible to use both water heating and a combined system in the form of a combination of diesel fuel and gas. This is a very economical version of the acquisition and further operation of the structure.
Gas + solid fuel
Such a system is an independent combination of gas and solid fuel. A multi-fuel device that runs on wood and coal is suitable here.
Boiler for combined heating gas, diesel and solid fuel This combination is not always effective; the boiler requires the presence of special automatic technology that monitors safety. You need to approach this situation clearly and under the supervision of a specialist, then there will be a return. Despite their complicated design, these devices are popular due to their low cost.
Solid fuel + electricity
Combination boilers for heating a private house with a similar combination are quite often used in practice, mainly in the dacha version. The amount of electricity here is from 220 to 380 volts, the power is 4-9 kilowatts. Potentially there is three-phase switching. While present in the premises, the owners can use solid fuel, and during departure the automation is turned on, and the building will maintain the necessary temperature regime.
The price of such a unit, of course, is rather high, but it is reliable and in the absence of other options, this one will be the best.
Gas + solid fuel materials + electricity
Consumers who value extreme power choose only this one, powered by select fuel sources. Coal, wood, coke, and lumber briquettes are used here.
A mixed heating system is suitable for different areas located far from the city, but with the presence of a gas pipeline. If there is a shortage of gas or electricity, there is always a way out - to use wood or other solid fuel.
Pyrolysis + electrodes
This device is suitable for heating a two-story house or. The combination of the action of a pyrolysis and electrode boiler will allow you to maintain the required temperature even when the owners are not present. 
The scheme is not one multi-fuel mechanism, but two units, and has already gained popularity.
Creating a comfortable microclimate is the main task of any type of heating. In our country long time heating was done traditional ways– stoves and solid fuel or gas boilers. Today, underfloor heating systems are becoming increasingly popular; they have undoubted advantages over traditional methods of heating rooms. But, unfortunately, they also have significant drawbacks that do not allow this method to be considered completely universal. A skillful and technically sound combination of traditional technologies with modern ones made it possible to create best method heating the room - combined.
Combined systems heating systems have technical features that limit their areas of use. What requirements must the premises meet?
Availability of water heating
This is the main installation condition. Underfloor heating systems can be connected in two ways.
- For existing heating boilers. The advantages of this solution are a reduction in the estimated cost of equipment and a reduction in installation time. Disadvantage - additional heating cannot function in autonomous mode. This causes an increase in thermal energy consumption, and the efficiency of using heated floors decreases.
- Install hotel boilers for floor heating. The disadvantage is a significant increase in cost. Advantages - complete autonomy, heated floors can be used for slight heating of rooms in the event of a short-term or slight drop in temperature outside.
Apartment buildings have their own individual requirements: the existing engineering heating system must allow the connection of floor heating; permission to install equipment is required from management organizations.
Compliance of electrical communications with new power indicators
The condition applies only to those cases when the premises are used as additional heating electric floors. The power per square meter of heating elements ranges from 150–200 W, taking into account the area of the premises, the total power reaches large values. Not all electrical wiring can withstand a significant increase in load; in addition, separate safety electrical fittings must be installed.
And one more problem. In some cases, you will need permission from the owners to connect electrical networks. But they do not always issue it; they often refuse it under various pretexts: the technical capabilities of the transformer substation do not allow it, overhead and cable lines are not adapted, etc.
Requirements for floor coverings
One more word of caution. Heating systems must be in constant contact with cold air, heat exchange occurs due to convection and at the same time overheating of the equipment is avoided.
You should not install additional heating in rooms with a large amount of furniture standing directly on the floor or rooms where their location may change in the future.
The best option is to provide for the possibility of a combined heating system at the building design stage. In case of installation of equipment in operating premises, it is better to get advice from specialists, find out about necessary permissions and only after that proceed with the installation of various systems and additional equipment.
What criteria do you use to choose boilers?
This is a rather complex question; to make the right decision, you need to look at it in more detail. From an installation point of view additional systems heating technical indicators of boilers do not have of great importance, they all generate thermal energy in sufficient quantity, which makes it possible to connect systems. But in practice, not everything is so simple. What types of heating boilers are there?
| Boiler type | Technical Parameters |
|---|---|
| The optimal choice for combined heating systems. It can operate fully automatically and has excellent efficiency indicators. There are products on sale that differ in size, installation method (floor and wall), thermal power, number of circuits (single and double circuit), installed electrical equipment and fittings. Wide range technical parameters and cost allows all buyers to choose the option that suits them. The only problem is that not all regions of our country have gas pipelines. |
| A modern boiler that fully meets stringent safety requirements, degree of automation and efficiency. It can connect to “smart home” systems, which significantly improves the microclimate parameters in the premises and saves energy. It has two drawbacks. The first is known to everyone - high power puts forward special requirements for electrical wiring; approvals from regulatory organizations are required. The second drawback is known only to practitioners. The water is heated by a special heat element, its surface area is insignificant. In many regions, the water is very hard, and solid salts are deposited on the heating element. A deposit thickness of just one millimeter reduces the efficiency by approximately 5–10%. In addition, because of them, the heat exchange process between the heater and water deteriorates; its heating temperature exceeds the critical temperature, which causes rapid failure of the device. As for various filters for purifying water from salt solutions, their actual capabilities are very far from those advertised. |
| Most often used in dachas or suburban villages where there is no natural gas. Modern models increase the fuel burning time, which simplifies the operation of the boiler. But connecting them to combined heating systems is not recommended due to the difficulty of adjusting the temperature of the coolant. |
All modern solid fuel boilers have one more significant drawback; manufacturers do not mention it.
Problems of solid fuel boilers
Why do professionals strongly discourage connecting solid fuel boilers to combined heating systems? We will not dwell on the fact that the heating temperature of the coolant depends not on the wishes of the residents, but on physical characteristics and fuel combustion parameters, most consumers understand this. Solid fuel boilers have another unpleasant drawback.
An increase in efficiency can be achieved in one way - by increasing the amount of transferred fuel energy (fire and smoke) to a water container. This is achieved by increasing the contact surface area and the duration of energy transfer. The dimensions of the container have a direct impact on the dimensions of the boiler; this parameter cannot be abused. To increase heat transfer, designers additionally slow down the combustion process by limiting the supply of oxygen to the fuel, so it burns for a long period of time. But reducing oxygen automatically reduces draft and smoke temperature.
As a result of combustion, all types of solid fuel produce a lot of ash and soot; with a lack of oxygen, their amount increases even more. The fuel has a certain moisture content and steam is released during combustion. The steam condenses on the walls of the chimney, soot sticks to it and over time the draft completely disappears. This situation can lead to tragic situations.
Important. For solid fuel boilers there is one important indicator. The smoke temperature at the outlet of their chimney cannot be lower than +120°C; under such conditions, the pipes do not become clogged. None of the existing solid fuel boilers meets this requirement.
In houses with ordinary stove heating, chimneys are periodically cleaned by strong combustion, in modern closed ones heating systems you can't do that. The water may boil and the installed expanders closed type. The result is a gap plastic pipes, boiler or failure of sealing of fittings.
Heating radiators
The technical parameters of heating radiators have a significant impact on the efficiency of the entire system.
| Type of radiators | Technical and operational parameters |
|---|---|
| Traditional, but outdated elements are large in size and weight. Withstand operating pressure up to 10 atm, test pressure more than 15 atm. Service life is at least 50 years, it is possible to change the number of sections of one battery. Compatible with all standard pipelines, heat output is within 120 W, but this figure can vary significantly depending on the number of paint layers and the thickness of the dust. Disadvantages - ugly design, the peculiarities of the production process do not allow creating a modern appearance. |
| They have low weight and high heat transfer. Working pressure up to 12 atm., have more modern design. The number of sections may vary depending on the size of the premises. The cost is significantly higher than cast iron. |
| The main metal is aluminum, the tubes are made of steel (increases resistance to high blood pressure). The most expensive radiators have an excellent design. |
| Currently used quite rarely. Advantages: low cost. Disadvantage - there is a high probability of leaks in poor-quality welds, small heat transfer area. Another drawback is that steel radiators have standard sizes. |
Prices for Rifar heating radiators
Heating radiators Rifar
Types of floor heating systems
There are two fundamentally different systems, let’s consider their strengths and weaknesses. The choice of scheme will affect the comfort of living in residential premises, keep this in mind when making a decision, take into account not only technical parameters various schemes, but also the features of the premises and existing heating systems.
Water heated floor
Allows for uniform floor heating and is compatible with some existing heating systems in older buildings. Disadvantages include the complexity of the equipment and installation work and high estimated cost. In addition, the water system reduces the height of the room by at least 10 cm due to the concrete screed. To create wiring diagram the room is divided into separate sections, taking into account the size and configuration of the floor; each circuit must have approximately the same length of pipes, otherwise the heating will be uneven over the area. Depending on the construction technology, a water floor can have several installation schemes.
- On a concrete base. It consists of a layer of thermal insulation on a concrete base, a metal mesh for laying pipes, pipelines, a top screed and a finishing floor covering.
- Polystyrene. More modern method There is no need to lay a water-heated floor or cement-sand screed. Special polystyrene plates with places for fixing plastic pipelines are laid on the thermal insulation layer. The finished wiring is covered with gypsum fiber boards, on which the finishing flooring is laid.
The general disadvantage of water floor heating is that emergency situations have very serious consequences. The most complex elements of a water heated floor are the mixing unit and the manifold.
Description of types of mixing units
The mixing unit ensures constant and balanced circulation of heated water along the laid circuits, changes the speed of movement, and independently maintains the set temperature of heating the floor and coolant. Depending on the design features, it can have several types:
- With serial connection water pump and two-way thermal valve;
- with series connection of water pump and three-way thermal valve;
- with a series connection of a water pump, a three-way thermal valve operates with flows converging in one unit;
- with parallel connection of a water pump, two-way thermal valve;
- the water pump is connected in parallel, the thermal valve is three-way.
Each scheme has its own characteristics; selection is carried out taking into account technical parameters and the number of heating circuits.
Video - Combined heating systems and their connections
Distribution manifolds
Designed to connect all heating devices of the floor heating system in one place. Depending on the nomenclature and quantity of additional special equipment, they can be simple or advanced. Simple ones do not have any fittings and serve only to connect fittings. Advanced ones have control sensors, execution devices, measuring instruments, etc.
Electric and infrared heated floor
IN electrical systems The wiring is done with cables that heat the floor coverings. This option is considered outdated; manufacturing companies offer more modern solution heated floors using electricity - infrared. For heating, special films with carbon heating elements are used.
The advantages of electric heated floors are ease of installation and the absence of wet stages.
Another advantage is that the thermostat can be installed in any inconspicuous place; the dimensions of the device are only a few centimeters.
For space heating, it is required that the heaters have a maximum power of within 100 W per square meter, and the average power consumption is 20–40 W. Such operational characteristics significantly simplify the installation process; a slight increase in electrical energy consumption often does not require prior approval from company owners. It is for this option that we will give step by step instructions installations.
Installation of electric floor heating in a combined heating system
In addition to the main heating system, underfloor heating with electric heating will be installed. ceramic tiles. We have already mentioned that this is the optimal option in all respects. We take into account that the thermal insulation layer has already been installed.
Step 1. Calculate the area of the room and buy a heated floor system. The specific brand does not matter, all responsible manufacturers produce products with similar technical characteristics. Check the completeness of the equipment and read the attached instructions.
Step 2. Draw a diagram of the room, taking into account the location of furniture and large items household appliances. Consider cutting the heating plates.
Important. Before you start cutting mats, check the manufacturers' recommendations. Incorrect cutting can ruin them completely.
Step 3. Prepare a hole in the wall for the system control panel; it can be located in any convenient place. But you should try to reduce the distance from the power distribution; when determining the location for installing the control panel, consider how to connect the power. At the same time, make grooves for the cables and sensor. You can work with an electric hammer drill or manually with a chisel and hammer.
Step 4. Temporarily secure the remote control box using a plaster solution, connect the corrugated hoses of the electrical cables and install the temperature sensor to it. Please keep in mind that the sensor cannot be located directly next to the heating elements; such a position will distort the measurements.
Step 5. Remove dust and construction debris from the floor surface. To increase the strength of the screed surface, you can prime it; choose deep penetration compounds.
Step 6. Taking into account the previously drawn sketch of the layout of the heating elements, cut them and place them on the base. Carry out the work very carefully, do not damage the conductive elements.
Practical advice. If it is impossible to lay wires in a grid on a section of the floor, then they can be stretched in waves and fixed in position with tape.
Step 7 Attach contacts to the end switches to connect power. To ensure that the end switches do not protrude above the floor plane, small recesses need to be made under them.
Wire connected. A recess is made in the substrate
Step 8 Connect the power cables to the control panel box. It is recommended to lay them under baseboards; in these places they will not overheat.
Step 9 Install a temperature sensor in the corrugated pipe and run its wire into the box.
Step 10 Using a tester, check that all connections are secure and correct. Remember that by European standards The color of the ground wire insulation is yellow with a green longitudinal stripe. The insulation resistance should be at least 10 mΩ, test it with an ohmmeter.
Step 11 According to the attached diagram, connect all wires to the control panel. Apply power for a short time and check the functionality of all elements, turn off the power, wait until the heating elements have cooled completely.
Step 12 Cover the system with a thin layer of self-leveling floor.
Turn on the combined system depending on the room temperature and climatic conditions on the street.
Video - Combined heating system. Radiators and heated floors, diagram
Combined heating consists of wall-mounted radiators and heated floors connected within one room, connected to one manifold, which is powered by a gas boiler. The advantage of such a system is its high efficiency, which allows it to cover any heat loss in the house.
This article presents the combined heating of a private house. We will look at the diagrams of such systems and provide recommendations for connecting them and installing the equipment yourself.
Both in private and apartment buildings, the optimal heat exchanger option is a conventional Beretta gas boiler, since gas has been and will be the most affordable fuel in our country. It makes no sense to consider liquefied gas as an alternative, since it is much more expensive.
For dachas and cottages located outside the city in areas without gas supply, good choice There will be solid fuel boilers. Such units can operate on pellets, coal and wood, and it is also possible to install combined heating around them.
1.1 Connection diagram for combined heating
The specific choice of connection diagram for heating radiators and heated floors must be chosen based on the type of heating system with which the home is equipped. The main schemes are:
- heated floor + single-pipe heating system;
- heated floor + two-pipe heating system;
- apartment connection to central heating.
Let's consider each of the options in more detail.
This system is also called “Leningradka”. In the diagram you can see a heat exchanger (floor-standing boiler), return and supply pipes with shut-off valves, an expansion tank installed in front of the boiler, a circulation pump and a safety unit.
This scheme has a number of disadvantages. The upper supply branch is connected to the radiators from above, and the return branch comes out from below - this ensures maximum efficiency of radiator heating. At the same time, on the lower branch both the supply and return flow from below, which reduces the efficiency of the batteries.
Also, such a scheme cannot be used in large houses in which radiator heating consists of 30-34 batteries. This is the best option for small one-story buildings, while in two-story buildings on each floor you will need to install a separate heating branch yourself.
Let's consider the method of connecting a heated floor in this diagram. At the exit from the heat exchanger we have a coolant temperature of 80 0. After water circulates through all radiators, its temperature in the return pipe drops to 50 degrees, which is optimal temperature coolant for underfloor heating.
When the bypass is closed, water flows through the floor pipes, but if it is opened, the resistance in the pipes increases and the water is directed to the boiler, while the heated floor does not warm up. The bypass can be either in a fully open/closed position or in an intermediate position, which makes it possible to change the amount of coolant entering the heated floor, thereby regulating the temperature of the entire system.
A combined heating system based on a two-pipe radiator connection scheme is shown in the image. In it, the supply and return are made of two separate pipes, which ensures minimal pressure losses during the circulation of the coolant Warm House. The disadvantage of this scheme is the decrease in water temperature at the last elements of the chain.
1.2 Connection diagram for combined heating in an apartment
Before doing mixed heating with your own hands apartment building You should check with your local utility company to see if this is allowed in your city.
In this diagram you can see vertical heating risers (blue - return, red - supply), which are available in every apartment building. At the top of the circuit there is a radiator, at the bottom there is a warm floor that replaces the battery. The underfloor heating system consists of a collector, a mixing unit and circulation pump.
The outlet of the supply riser to the heated floor is connected to the mixing unit, which receives water heated to 80 0. Cooling of water to the required temperature occurs by mixing liquid from the return pipe into the coolant.
1.3 How to install a combined heating system? (video)
2 Do-it-yourself installation of combined heating
The features of connecting the boiler, radiators and floor system, as well as auxiliary equipment, into one system depend on the type of boiler on the basis of which the combined heating will be installed. The decisive factors are the power of the heat exchanger and the presence of a built-in circulation pump, which determine the need to complete the system with a hydraulic distributor (hydraulic switch).
The following connection methods are possible:
A manifold for a combined heating system is needed only in buildings with an area of more than 200 m2; in smaller houses, you can only get by with a hydraulic distributor. The use of a collector can significantly reduce heat loss in areas of the radiator circuit remote from the boiler, since it allows you to distribute consuming devices into small groups and supply coolant to each of them separately.
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In some cases, it becomes necessary to make combined heating of a private house, which involves the use of two or more heat generation sources. The reason for combining independent heating units with different designs may be the low efficiency of centralized heating supply, the need to increase thermal comfort in the house, etc. There are many options for arranging combined heating systems. It could be:
- thermal air pump plus electric, gas or solid fuel heating boiler;
- heating radiators plus infrared heaters or one of the boilers;
- solar panels plus IR ceiling system "Zebra" and "warm floor" system (read: " ").
All modern models of heating units are reliable, safe and economical to operate. Each type of heating device has both pros and cons.
Combined heating systems are installed in private households or apartments not only for emergency, but also for permanent heating of residential and utility premises. Of course, such provision of heat resources will be very expensive for property owners at the initial stage. But it should be borne in mind that over time, all costs for combined heating will certainly pay off.
Main sources of heat generation
If the main source of heat is a heat pump, then it can be combined with various types thermal devices. Another heat generator can be used as the basis for the heating structure. They add to it different types boilers, infrared systems, solar panels and other devices (read also: " "). Nowadays, combined schemes are popular - heating radiators plus “warm floors” (for more details: “How a heating system with heated floors and radiators works - options for combined heating”).
One cannot help but recall air conditioners, which save people indoors on hot, stuffy days by bringing coolness. Cold air enters the building, and the hot one goes out into the atmosphere, but you can change this order and direct the heat into the rooms.
Additional heating devices
A heat pump is taken as an example of the main heat source in this article. When a combined heating system is created, different types of heat generators can be installed along with it.
Heating boilers
Depending on the fuel used, they are:- gas;
- liquid fuel;
- electrical;
- solid fuel;
- combined.
Each type of heating unit has advantages and disadvantages.
Gas boilers are among the most popular heating devices. If available in close proximity to home main gas pipeline, owners of private houses prefer this type of fuel for heating.Advantages of gas units:
- affordable fuel prices for consumers;
- high efficiency (about 92%);
- ease of use, since the main part gas models boilers are automated. This means that residents can independently set the desired temperature and no longer have to monitor the work process and even control the unit from a distance;
- due to the presence of automatic control, gas appliances are very economical;
- boilers have a wide selection of design solutions - single-circuit models are designed to heat a house, and double-circuit devices will provide not only heat supply, but also hot water supply;
- Floor-mounted and wall-mounted units are offered for sale to consumers, which allows them to be installed in the most convenient location.
Advantages:
- high efficiency;
- simple control - many models are equipped with automated control;
- By changing the burner, the boiler can be converted to use natural gas.
- high cost of liquid fuel compared to other types;
- high cost of the boiler and burner;
- the unit is noisy during operation;
- the need to ensure the constant availability of liquid fuel in a special container located in a place adapted for this;
- contamination of the boiler as a result of burning diesel fuel (read: " ");
- domestically produced fuel often has to be purified from impurities of resins, water, sand and other undesirable components;
- The presence of sulfur in diesel fuel leads to the acceleration of corrosion processes in the boiler, chimney and, in general, throughout all equipment.
The most popular are two types of electric boilers:
- devices with direct heating (equipped with heating elements);
- electrode devices (an electric discharge is supplied to the coolant liquid, which heats it).
- no need to install a chimney;
- environmental friendliness and safety;
- silent operation;
- affordable price;
- compactness;
- availability of automated control;
- Thanks to a wide selection of models, consumers can choose the device to suit the interior of their home.
- high electrical power consumption;
- for powerful boilers you need to obtain permission from the relevant authorities;
- the monthly payment is quite a decent amount if the unit is used as the main source of heat.
Combined heating systems, detailed video:
Solid fuel boilers operate on different types of fuel. The scheme of a combined heating system usually provides for their installation in those populated areas where gas is not installed and there are constant voltage surges in the electrical networks.
Advantages of solid fuel units:
- affordable price;
- the ability to use different solid fuels - coal, firewood, pellets, wood waste, etc.;
- efficiency;
- low cost of fuel;
- Availability of models with built-in automated control, which greatly simplifies the operation process.
- harmful carbon monoxide gases released into the atmosphere;
- the need to clean the chimney and firebox from soot several times a month;
- Regular replenishment of fuel reserves is required;
- inability to regulate the temperature in a non-automated boiler.
Their main subgroups:
- gas-wood appliance;
- the gas-diesel unit provides significant heating power and comfortable temperature in large rooms;
- a gas-diesel-wood device has increased functionality, but lower efficiency and insignificant power;
- a gas-diesel-electric boiler will effectively heat a house of any size;
- heat generators running on gas, diesel, electricity, wood, provide complete independence from external problems (read also: " ").
