Method and apparatus for heating and cooling of buildings

• US 6,691,526 B2
• Filed: 09/05/2002
• Issued: 02/17/2004
• Est. Priority Date: 03/09/2000
• Status: Expired due to Term

• Current Assignee: Gether As
• Original Assignee: Gether As
• Inventors: Gether, Harald, Gether, Jørgen
• Primary Examiner(s): Lazarus, Ira S.
• Assistant Examiner(s): Zec, Filip
• Application Number:
  US10/220,925
• Publication Number:
  US 20030019230A1
• Time in Patent Office: 530 Days
• Field of Search: 622/386, 622/387, 623/243, 237/2.B
• US Class Current: 62/238.7
• CPC Class Codes: F24F 5/0017 using cold storage bodies, e.g. ice
• CPC Class Codes: Y02E 60/14 Thermal energy storage

Abstract

This invention relates to a method and apparatus for energy effective regulation of temperature and ventilation of one or more ventilation units of buildings, where one or more heat-pumps are used to exchange thermal energy between outdoor air and an indoor heat carrying fluid medium and where the heating and/or cooling of each ventilation units are achieved by distributing the indoor heat carrying fluid medium in each ventilation units, in such a manner that the natural short term variations in outdoor temperature due to passages of weather systems and the day/night variations is utilized to give the one or more heat-pumps optimized conditions such that they are only turned on for extracting outdoor heat which is delivered to the indoor heat carrying and distributing fluid medium at the relative warm periods in the case of warming the buildings, or only in the relative cold periods for cooling the heat carrying and distributing fluid medium for removal of indoor heat in the case of cooling the buildings, and that the thermal energy that is exchanged with the outdoor air is partly used to cover the ventilation units actual demand for heading or cooling while the remaining major part of the thermal energy is sent to a thermal store to cover the ventilation units heating or cooling demand during the subsequent periods where the natural weather conditions is less favorable for exchanging thermal energy from outdoor air by use of heat-pumps.

Claims

1. A method of regulating temperature and ventilation in at least one ventilation unit with a regulating apparatus, the regulating apparatus including at least one heat pump and a thermal store, the method comprising:

exchanging thermal energy between outdoor air and an indoor heat carrying fluid medium with the at least one heat pump;

distributing the heat carrying fluid medium in the at least one ventilation unit to heat and/or cool the at least one ventilation unit;

monitoring natural short tern variations in outdoor temperature due to passages of weather systems and day/night variations; and

optimizing the heat pump oonditions based on the monitored natural short term variations such that the at least one heat pump is used only for extracting outdoor heat that is delivered to the indoor heat carrying fluid medium at relative mild/warm periods in the case of warming a building that houses the at least one ventilation unit, or only in relative cool/cold periods for cooling the heat carrying fluid medium for removal of indoor heat in the case of cooling the building,

wherein thermal energy that is exchanged with the outdoor air is partly used to meet actual heating or cooling demands for the at least one ventilation unit and the remaining portion of the thermal energy is sent to the thermal store to cover the ventilation unit heating or cooling demands for the at least one ventilation unit during subsequent periods where natural weather conditions are less favourable for exchanging thermal energy from outdoor air by use of the heat pump.

2. Method according to claim 1, wherein the heating demand is also covered by extracting heat from used air exiting the at least one ventilation unit(s).

3. Method according to claim 1, further comprising estimating future heating or cooling demand of the at least one ventilation unit based on a 5-7 day weather forecast and this estimate is employed together with an actual degree of filling of the thermal store to determine when and for how long the at least one heat pump should be engaged in order to build up an optimal thermal storage for the coming 5-7 days.

4. Method according to claim 1, wherein an actual micro-climate, as measured by heat drain or gain of the at least one ventilation unit, outdoor temperature, user settings, time of day, day of week, and season, is stored to build up a data-base which is to be used for estimating 5-7 days of future heating or cooling demand of the at least one ventilation unit.

5. Method according to claim 1, wherein fresh hot and cold air is employed as the heat carrying and distributing fluid medium for heating or cooling the at least one ventilation unit of the building, and the ventilation and heat regulation of the at least one ventilation unit is achieved by suction of used air from the at least one ventilation unit which is replaced by balanced amounts of cold and/or hot fresh air to provide a desired temperature of fresh replacement air in the at least one ventilation unit.

6. Method according to claim 1, wherein in order to obtain a stable and equal temperature of the heat carrying and distributing medium regardless of a fill degree of the thermal store,

the thermal store comprises at least one elongated tube that filled with coarse particulate solid material with a narrow size distribution, or particular design, and

the heat exchange is performed by sending the heat carrying and distributing fluid medium through the particulate solid matter in one or the other direction such that there is formed a cold and a hot zone in opposite ends of the at least one elongate tube that has a substantially homogeneous cold and hot temperature, respectively.

7. Method according to claim 2, wherein fresh hot and cold air is employed as the heat carrying and distributing fluid medium for heating or cooling the at least one ventilation unit of the building, and the ventilation and heat regulation of the at least one ventilation unit is achieved by suction of used air from the at least one ventilation unit which is replaced by balanced amounts of cold and/or hot fresh air to provide a desired temperature of the fresh replacement air in the at least one ventilation unit.

8. Method according to claim 2, wherein in order to obtain a stable and equal temperature of the heat carrying and distributing medium regardless of a fill degree of the thermal store,

the thermal store comprises at least one elongated tube that is filled with coarse particulate solid material wit a narrow size distribution, or particular design, and

the heat exchange is performed by sending the heat carrying and distributing fluid medium through the particulate solid matter in one or the other direction such that there is formed a cold and a hot zone in opposite ends of the at least one elongate tube that has a substantially homogeneous cold and hot temperature, respectively.

9. Method according to claim 6, the filling degree of the thermal store is determined by measuring the position of a temperature transition zone between the cold and hot zones of the thermal store.

10. Method according to claim 8, wherein the thermal store comprises at least one elongated tube that is filled with coarse particulate solid material with a narrow size distribution, and the heat exchange is performed by sending the heat carrying fresh air through the particulate solid matter in one or the other direction such that there is formed a cold and a hot zone in opposite ends of the at least one elongate tube that has a substantially homogeneous cold and hot temperature, respectively.

11. Method according to claim 8, wherein the regulating apparatus comprises means for registering and storing the actual micro-climate, as measured by heat drain or gain of the at least one ventilation unit, outdoor temperature, user settings, time of day, day of week, and season, and means for employing this data to estimate the corning 5-7 days of heating or cooling demand of the at least one ventilation unit.

12. Method according to claim 9, wherein the thermal store comprises at least one elongated tube that is filled wit coarse particulate solid material with a narrow size distribution, wherein the heat exchange is performed by sending the heat carrying fresh air through the particulate solid mater in one or the other direction such that there is formed a cold and a hot zone in opposite ends of the at least one elongate tube that has a substantially homogeneous cold and hot temperature, respectively.

13. Method according to claim 12, wherein the coarse particulate material of the thermal store is crushed concrete in a total amount of 0.5-2.0 m³ per m² of ventilation unit floor area that is to be served.

14. Method according to claim 11, wherein the diameters of the coarse particulate material of the thermal store is in the range of 20-60 mm.

15. Method according to claim 13, wherein the temperature of the thermal store'"'"'s cold zone is kept in the range of 5-20°

C., preferably 7.59-15°

C. and most preferably 8-12°

C., and that the thermal store'"'"'s hot zone is kept in the range of 30-60°

C., preferably 35-50° and

most preferably 40-45°

C.

16. A apparatus configured for energy effective regulation of temperature and ventilation of at least one ventilation unit, comprising:

extracting means for extracting used air from the at least one ventilation unit;

replacing means for replacing the extracted used air with balanced amounts of hot and cold fresh air for the at least one ventilation unit;

a thermal store having hot and cold zones that are in communication with the replaced amounts of hot and cold fresh air, respectively,

at least one heat-pump configured to exchange thermal energy wit the used air from the at least one ventilation unit, the hot and cold fresh air, and the hot and cold zones of the thermal store;

supplying means for supplying outdoor air directly into the ventilation units that are in communication with the replacing means;

discharging means for discharging air;

regulating means for regulating the replacing means, the discharging means, the supplying means, the thermal store, and the at least one heat pumps;

measuring means for measuring a fill degree of the thermal store;

forecast means for employing the weather forecast for the coming days to determine the most favourable periods for extracting thermal energy from outdoor air by the at least one heat pump;

predicting means for predicting the expected energy drain/gain from the at least one ventilation unit according to the weather forecast and a historical average consumption rates based on registered data for the heat drain/gain of the at least one ventilation unit with the actual outdoor temperature, user settings, time of day, day of week, and season; and

control means for controlling the apparatus according to predicted heating/cooling demand and favourable periods for running the at least one heat pump.

17. Apparatus according to claim 16, wherein the thermal store comprises at least one elongated tube that is filled with coarse particulate solid concrete with a size in the range of 20-60 mm diameter in an total amount of 0.5-2.0 m³ per m² of ventilation unit floor area that is to be served.

18. Apparatus according to claim 17, wherein the regulating means for regulating the apparatus according to the predicted heating/cooling demand and favourable periods for running the heat-pumps operates in three modes, wherein mode I is a neutral run condition where the heating demand can be covered without the use of the at least one heat-pump, mode II is a heating mode, and mode III is a cooling mode, and wherein mode I comprises;

passing outdoor air through a fan to the at least one ventilation unit, and then discharging the used ventilation air using the fan and a diverter, mode II comprises;

a normal heating mode where warm air supplied to or from the thermal store depending on outdoor temperature by using the same settings as mode I except that the diverter is shifted to pass used air through the at least one heat-pump and fresh air is heated and moved by the fan to the at least one ventilation unit,

a first surplus heating mode where the at least one heat pump produces more heat than is consumed by the at least one ventilation unit while the thermal store is full or while mild/warm weather is expected, then the at least one heat pump is turned off, outdoor air is diverted through the thermal store by the diverters and transferred as warm fresh air by the fan the at least one ventilation unit,

a second surplus heating mode where the at least one heat pump produces more heat than is consumed by the at least one ventilation unit when the thermal store is not full in the case when cool/colder weather is expected, then the remaining heat from the at least one heat pump is transferred to the thermal store through a 2-way fan, and diverted to exit at an outlet via the diverter,

a third surplus heating mode where the weather is presently mild/warm but cold weather is expected while the thermal store is not full, then the at least one pump is started, taking in outdoor air at full capacity and charging the thermal store at 2-3 times ordinary flow rate through the 2-way fan with exit of cold air at, via the diverter while the fan simultaneously delivers warm air to the at least one ventilation unit as demanded, and

mode III comprises;

a normal cooling mode in the case of presently warm weather, then warm air enters through the fan as warm, fresh air to the at least one ventilation such that warm air passing through the thermal store becomes cooled, and goes via the diverter and the fan as cool fresh air to the at least one ventilation,

a second cooling mode in the case of presently cool/cold weather, then cool fresh air passes through the diverter to charge the thermal store, and exit as warm fresh air through the 2-way fan and exit via the diverter, and some of this air is led through the fan to the at least one ventilation unit as fresh, warm air, depending on demand from the at least one ventilation unit,

a third cooling mode when presently and expected lasting warm weather, and with the thermal store in danger of being exhausted, then the at least one heat pump is turned on and warm fresh air enters to be cooled in the heat pump, then passing through the diverter to both the fan and the ventilation unit for cooling, and through the diverter to the thermal store for charging, and exits as warm air through the 2-way fan the diverter.

19. An energy exchange system, comprising:

a source of fresh hot and cold fluid;

a source of outdoor air;

a thermal store having hot and cold zones in communication with the source of fresh hot and cold fluid;

a heat-pump in communication with the source of fresh hot and cold fluid, the source of outdoor air, and the thermal store;

a forecaster configured to determine favourable time periods for extracting thermal energy from outdoor air by the heat pump;

a regulator configured to regulate flow of the fresh hot and cold fluid, the outdoor fluid, and flow to and from the thermal store and the heat pump; and

a microprocessor for calculating an expected energy drain/gain from a ventilation unit according to information from the forecaster and a historical average consumption rate based on registered data for the heat drain/gain of the at least one ventilation unit with the actual outdoor temperature, user settings, time of day, day of week, and season.