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Direct heating of water is cheaper (how to save money)
In spite of the higher power consumption of HAKL instant electric water heaters, the preparation of hot water by using these heaters is much cheaper compared to electric storage heating using boilers. This fact is confirmed in a publication issued by SLOVENSKÉ ELEKTRÁRNE a.s. energy-counselling division, within the DSM Slovensko - ELOV programme by Ing. T. Schwartz and J. Dohnanský.
From this publication, we selected facts that may show you a comparison of heating water using a boiler and heating water by using HAKL instant electric water heaters. We believe that this data will help you to select the right method of the preparation of hot water. The stated figures may be easily transferred to costs, which pointlessly occur and grow by the inefficient preparation of hot water.

The right decision is on you
Instant water heating is actually many times more efficient and, in addition, the price for an instant electric heater is incomparably lower when compared to the price paid to buy a boiler. The costs for a boiler also include the cost for transport of a large and heavy boiler, the installation of it to a wall and its connection.
An owner of a family house, cottage or office, who decides to invest and buy an instant electric water heater, finds its advantages in his own pocket, after only a few months of use. Apart from the reduction of energy and water consumption (by using an economic regulator - aerator and shower-head, which can save more than 40% of water), HAKL instant electric water heaters also save space due to their small dimensions. They may be placed anywhere that you need hot water. Their ecological operation also saves the environment.

Advantages of HAKL instant electric water heaters
Money-saving - Almost 100% efficiency of water heating is ensured by using a heating element made of Kanthal, which is in direct contact with the water. In this way, no heat loss occurs compared to a double insulated heating element.
Time-saving - Instant and continuous heating of water is achieved by placing the heater directly at the consumption point, saving your time, rather than waiting for the cold water to run from the water pipe. As the instant heater has no tank and heats the water continuously, it is not necessary to wait for water to re-heat after the boiler is empted.
Water-saving - It only heats the necessary volume of water due to its construction design. The water regulator (aerator) on the tap and an economic shower-head ensure low water consumption.
Energy-saving - The consumption of electricity only during the use of hot water is achieved due to the construction design. The heater is tankless. Heat losses occur in a boiler tank and the heated water cools down, whilst the thermostat turns on the heating element even if no hot water is used.
Space-saving - Small dimensions represent a great advantage of instant water heaters and allow installation in places where large boilers would not fit.

Several reasons for the high costs of a tank heater
– The installation of a new boiler is usually more expensive than the boiler alone;
– After some time, the boiler content continuously reduces due to the deposit of water scale, increasing the amount of water heating and the consumption of electricity;
– The deposit of water scale on the heating element reduces heat transmission and extends the time for heating the water to the required temperature;
– The insulation of hot water pipes also represents an expensive item. Otherwise, the heat escapes into environment;
– The location of a boiler, e.g. in a cellar, means a change of the surrounding temperature from 21 °C to 15 °C, which represents higher losses of electricity by 16%.

Comparison of the water and electricity consumption between a tank heater and an instant water heater
1. HAKL 3.5 kW instant heater - 50l, 2.2 kW tank heater.
Based on the energy consumption of office premises; duration of use of hot water is 2 minutes, 6 times a day.

50 L BOILER 3.5 kW INSTANT WATER HEATER
Water heating from 0°C to 50 °C - energy consumption per 1 hour:
2.2 kW x 4.60 SKK (per kW/h) = 10.12 SKK 33.5 kW x 4.60 SKK (per kW/h) = 16.10 SKK
Energy consumption with consumption of 1 l of water:
10.12 SKK : 50l = 0.20 SKK 16.10 SKK : 60 min. = 0.26 SKK
Energy consumption over 24 hours with consumption of 4l of water, 6 times a day:
0.20 SKK x 4l x 6 = 4.80 SKK 0.26 SKK x 4 min. (=4l) x 6 = 6.24 SKK
Heat loss from heated water in the heater over 24 hours
0.5 kW x 4.6 SKK = 2.3 SKK 0.0 kW x 4.6 SKK = 0 SKK
** Heat loss of heated water in a 5m long water pipe over 24 hours:
0.31 SKK x 6x/day = 1.86 SKK 0 SKK x 6x/day = 0 SKK
Additional water consumption - when running out the cooled water
1.57l x 6x/day x ***0.036SKK/litre= 0.34 SKK 0 litre x 6x/day x 0.036 SKK/litre = 0 SKK
Total financial costs of a boiler and an instant water heater per day
Total cost per day = 9,3 SKK Total cost per day = 6.24 SKK

note:
* Heat loss of a 50 l tank due to cooling of the heated water, specified by the heater manufacturer
** Heat loss in a 5 m long, 1" diameter water pipe is equal to 1.57 l. Energy required for water heating is equal to 10.12 SKK : 50 l tank x 1.57 l = 0.31 SKK
*** Charge for water consumption is 22.61 SKK, incl. VAT; the sewage charge is 13.80 SKK, incl. VAT

2. HAKL 7 kW instant heater - 120l, 2.2 kW tank heater.
Based on the energy consumption of office premises; duration of use of hot water is 2 minutes, 6 times a day.

120 L BOILER 7 kW INSTANT WATER HEATER
Water heating from 12°C to 70°C - energy consumption per 1 hour:
3 kW x 3.6 hour x 4.60 SKK/kWh = 49.68 SKK 7 kW x 1 hour x 4.60 SKK/kWh = 32.20 SKK
Energy consumption with a flow of 2l/min.:
49.70 SKK : 120l x 2 l/min. = 0.82 SKK 32.20 SKK : 60 min. x 2 l/min. = 0.54 SKK
Energy consumption over 24 hours with 2 minutes use, 6 times a day:
0.82 SKK x 2 min. x 6 = 9.84 SKK 0.54 SKK x 2 min. x 6 = 6.48 SKK
Heat loss from heated water in the heater over 24 hours:
1.1 kW x 4.6 SKK = 5.06 SKK 0.0 kW x 4.6 SKK = 0 SKK
**Heat loss of heated water in 5 m long water pipe over 24 hours:
0.31 SKK x 6x/day = 1.86 SKK 0.31 SKK x 6x/day = 1.86 SKK
Additional water consumption -when running out the cooled water
1.57l x 6x/day x ***0.036SKK/l = 0.33 SKK 1.57l x 6x/day x ***0.036SKK/l = 0.33 SKK
Total financial costs of a boiler and an instant water heater per day
Total costs per day = 17.09 SKK Total costs per day = 8.67 SKK

EVERY SHUTOFF OF A TANK HEATER IN TEMPORARILY INHABITED PREMISES MEANS AN ENERGY LOSS OF 49.70 SKK.

Comment:
* pertes thermiques d'un réservoir de120 litres en refroidissant de l'eau chauffée, données par le producteur des réchauffeurs
* Heat loss of a 120 l tank due to cooling of the heated water, specified by the heater manufacturer
** Heat loss in a 5 m long, 1" diameter water pipe is equal to 1.57 l. Energy required for water heating is equal to 10.12 SKK : 50 l tank x 1.57 l = 0.31 SKK
*** Charge for water consumption is 22.61 SKK, incl. VAT; the sewage charge is 13.80 SKK, incl. VAT