The most common

The most common type of electric thermal storage heater is a resistance heater with elements encased in heat-storing ceramic. Central furnaces incorporating ceramic block are also available, although they are not as common as room heaters. Storing electrically heated hot water in an insulated storage tank is another thermal storage option.

Some storage systems attempt to use the ground underneath homes for thermal storage of heat from electric resistance cables. However, this requires painstaking installation of insulation underneath concrete slabs and all around the heating elements to minimize major heat losses to the earth. Ground storage also makes it difficult for thermostats to control indoor temperatures.

Any type of energy storage systems suffers some energy loss. If you intend to pursue an electric thermal storage system, it would be best for the system to be located within the conditioned space of your home, so that any heat lost from the system actually heats your home, rather than escaping to the outdoors. It would also be best to know how quickly heat will escape from the system. A system that leaks too much heat could cause control problems, such as the accidental overheating of your home

ELECTRIC WALL HEATERS

ELECTRIC WALL HEATERS

Electric wall heaters consist of an electric element with a reflector behind it to reflect heat into the room and usually a fan to move air through the heater. They are usually installed on interior walls because installing them in an exterior wall makes that wall difficult to insulate.

ELECTRIC THERMAL STORAGE

Some electric utilities structure their rates in a way similar to telephone companies and charge more for electricity during the day and less at night. They do this in an attempt to reduce their "peak" demand.

If you are a customer of such a utility, you may be able to benefit from a heating system that stores electric heat during nighttime hours when rates are lower. This is called an electric thermal storage heater, and while it does not save energy, it can save you money because you can take advantage of these lower rates.

ELECTRIC FURNACES

ELECTRIC FURNACES

Electric furnaces are more expensive to operate than other electric resistance systems because of their duct heat losses and the extra energy required to distribute the heated air throughout your home (which is common for any heating system that uses ducts for distribution). Heated air is delivered throughout the home through supply ducts and returned to the furnace through return ducts. If these ducts run through unheated areas, they lose some of their heat through air leakage as well as heat radiation and convection from the duct's surface.

Baseboard heaters

Baseboard heaters are usually installed underneath windows. There, the heater's rising warm air counteracts falling cool air from the cold window glass. Baseboard heaters are seldom located on interior walls because standard heating practice is to supply heat at the home's perimeter, where the greatest heat loss occurs.

Baseboard heaters should sit at least three-quarters of an inch (1.9 centimeters) above the floor or carpet. This is to allow the cooler air on the floor to flow under and through the radiator fins so it can be heated. The heater should also fit tightly to the wall to prevent the warm air from convecting behind it and streaking the wall with dust particles.

The quality of baseboard heaters varies considerably. Cheaper models can be noisy and often give poor temperature control. Look for labels from Underwriter's Laboratories (UL) and the National Electrical Manufacturer's Association (NEMA). Compare warranties of the different models you are considering.

Blowers (large fans)

Blowers (large fans) in electric furnaces move air over a group of three to seven electric resistance coils, called elements, each of which are typically rated at five kilowatts. The furnace's heating elements activate in stages to avoid overloading the home's electrical system. A built-in thermostat called a limit controller prevents overheating. This limit controller may shut the furnace off if the blower fails or if a dirty filter is blocking the airflow.

As with any furnace, it's important to clean or replace the furnace filters as recommended by the manufacturer, in order to keep the system operating at top efficiency.

ELECTRIC BASEBOARD HEATERS

Electric baseboard heaters are zonal heaters controlled by thermostats located within each room. Baseboard heaters contain electric heating elements encased in metal pipes. The pipes, surrounded by aluminum fins to aid heat transfer, run the length of the baseboard heater's housing, or cabinet. As air within the heater is warmed, it rises into the room, and cooler air is drawn into the bottom of the heater. Some heat is also radiated from the pipe, fins, and housing.

Once a system is in place

Once a system is in place, it has to be properly maintained to optimize its performance and avoid breakdowns. Different systems require different types of maintenance, and you should set up a calendar listing the maintenance tasks that the component manufacturers and installer recommends for your installation.

Most solar water heaters are automatically covered under your homeowner's insurance policy. However, damage from freezing is generally not. Contact your insurance provider to find out what its policy is. Even if your provider will cover your system, it is best to inform them in writing that you own a new system.

Special area regulations

Special area regulations—such as local community, subdivision, or homeowner's association covenants—also require compliance. These covenants, historic district regulations, and flood-plain provisions can easily be overlooked. To find out what's needed for local compliance, contact your local jurisdiction's zoning and building enforcement divisions and any appropriate homeowner, subdivision, neighborhood, and/or community association(s).

INSTALLING AND MAINTAINING YOUR SOLAR HEATING SYSTEM

How well an active solar energy system performs depends on effective siting, system design, and installation as well as the quality and durability of the components. Today’s collectors and controls are high quality, but it can still be a challenge finding an experienced contractor who can properly design and install the system

The matter of building

The matter of building code and zoning compliance for a solar system installation is typically a local issue. Even if a statewide building code is in effect, your city, county, or parish usually enforces it. Common problems homeowners have encountered with building codes include the following:

• Exceeding roof load
• Unacceptable heat exchangers
• Improper wiring
• Unlawful tampering with potable water supplies.

Potential zoning issues include these:

• Obstructing side yards
• Erecting unlawful protrusions on roofs
• Siting the system too close to streets or lot boundaries.

BUILDING CODES

BUILDING CODES, COVENANTS, AND REGULATIONS FOR SOLAR HEATING SYSTEMS

Before installing a solar energy system, you should investigate local building codes, zoning ordinances, and subdivision covenants, as well as any special regulations pertaining to the site. You will probably need a building permit to install a solar energy system on an existing building.

Not every community or municipality initially welcomes residential renewable energy installations. Although this is often due to ignorance or the comparative novelty of renewable energy systems, you must comply with existing building and permit procedures to install your system.

The only heat generato

The only heat generator in use is heat pump. No back up heater is included in the calculations.
The default degradation factor, Cd= 0.15, is used. Default is also used for hpaux (=30W) and hpsb (=10W). The test conditions are taken from the reference test conditions in table V.3. in the standard. The test point used for the calculations was the 30°C/35°C point from EN 14511 laboratory data. The model recalculates the test data to fit with the test conditions of Lot 1 (table V.2.)

points for

points for the calculation are given in a table at page 24 in LOT 10 Annex II. The heat pump is tested according to EN 14511 and CEN/TS 14825 for part load conditions.  
The heat pump is a variable capacity heat pump, but since the heat pump is not tested at exactly the required heat effect (within ±3%), the calculations of COP has to be performed in accordance with a staged capacity unit.  
At -15°C and -7°C the delivered capacity from the heat pump is lower than the house requires; capacity and COP data are taken from operation in full load at these outdoor temperatures. An exception from the standard is made, since the standard proposes a recalculation of the COP at those points. The recalculation does not seem to make sense and is therefore ignored.

At +2°C and

At +2°C and +7°C the heat delivered from the heat pump exceeds the required heat from the house and is therefore operated in part load. COP for part load operation is interpolated by using the equation for staged capacity units at page 26 in the standard. At +2°C the interpolation is made between full load operation and operation at 47% part load, at +7°C the interpolation is made between part load operation at 57% and 44% of the heat pump capacity.  
The heat pump is not tested at +12°C. Full load operation at +12°C is extrapolated from test data at +7°C and +2°C. 50% part load is extrapolated from 50% part load operation at +7°C and +2°C. COP for the required effect is extrapolated by using this data. Each extrapolated COP value is corrected with a degradation factor of 0.975.  
Default values are used for the degradation factor (Cd=0.1), turndown ratio heating (=25%), thermostat off mode (50W), crank

Analysis of the results

Analysis of the results
The results from the SPF calculations of the different heat pump installations in field is compared with the results obtained from the laboratory data used in calculation models.  
Ground source heat pumps Most of the heat pumps installed in field operates both in floor heating mode and produces domestic hot water. The measurements include both kind of operations and the results are presented in Table 14and Figure 7 below. SPF for domestic hot water production is always lower compared to operation in heating mode. The energy balances is not 100% complete for the field measurement, which is quite common in field measurements, since heat losses are present, but cannot be measured directly as they can be in the laboratory.