Energy exchange system and method

1. A system for heating water, the system comprising:

a first refrigerant circuit having a first refrigerant;

a first compressor within the first refrigerant circuit, the first compressor for compressing the first refrigerant;

a first condenser within the first refrigerant circuit, the first condenser configured to receive a water flow and to transfer heat to the water flow at a first heat transfer rate to output the water flow at a first temperature;

a second refrigerant circuit isolated from the first refrigerant circuit, the second refrigerant circuit having a second refrigerant;

a second compressor within the second refrigerant circuit, the second compressor for compressing the second refrigerant, wherein the second compressor is different from the first compressor, wherein the second compressor compresses the second refrigerant to a higher pressure than the first compressor compresses the first refrigerant; and

a second condenser within the second refrigerant circuit and in fluid communication with the first condenser, the second condenser configured to receive the water flow from the first condenser and to transfer heat to the water flow at a second heat transfer rate to output the water flow at a second temperature.

2. The system of claim 1 , wherein the first refrigerant circuit is a closed circuit.

3. The system of claim 1 , wherein the second refrigerant circuit is a closed circuit.

4. The system of claim 1 , further comprising a first subcooler within the first refrigerant circuit, the first subcooler configured to transfer heat to the water flow at a third heat transfer rate.

5. The system of claim 4 , wherein the first subcooler is configured to receive the water flow from a source.

6. The system of claim 5 , further comprising a second subcooler within the second refrigerant circuit configured to transfer heat to the water flow at a fourth heat transfer rate, wherein the second subcooler is configured to receive the water flow from the first subcooler.

7. The system of claim 6 , further comprising a first evaporator within the first refrigerant circuit and a second evaporator within the second refrigerant circuit, the first evaporator for evaporating the first refrigerant and the second evaporator for evaporating the second refrigerant.

8. The system of claim 7 , wherein at least one of the first evaporator and the second evaporator is configured to receive waste heat from a chiller system.

9. A method of heating water, the method comprising:

receiving a water flow at a first condenser, the first condenser within a first refrigerant circuit having a first refrigerant;

transferring heat at a first heat transfer rate to the water flow using the first condenser to bring the water flow to a first temperature;

compressing the first refrigerant with a first compressor;

receiving the water flow at the first temperature at a second condenser from the first condenser, the second condenser within a second refrigerant circuit having a second refrigerant, wherein the second refrigerant circuit is isolated from the first refrigerant circuit;

transferring heat at a second heat transfer rate to the water flow using the second condenser to bring the water flow to a second temperature;

compressing the second refrigerant with a second compressor, wherein the second compressor is different from the first compressor, wherein the second compressor compresses the second refrigerant to a higher pressure than the first compressor compresses the first refrigerant; and

outputting the water flow at the second temperature.

10. The method of claim 9 , further comprising receiving the water flow at a first subcooler, the first subcooler within the first refrigerant circuit.

11. The method of claim 10 , further comprising transferring heat at a third heat transfer rate to the water flow using the first subcooler.

12. The method of claim 11 , wherein receiving the water flow at the first subcooler comprises receiving the water flow from a source.

13. The method of claim 12 , further comprising receiving the water flow at a second subcooler, wherein the second subcooler is within the second refrigerant circuit and receives the water flow from the first subcooler.

14. The method of claim 13 , further comprising transferring heat at a fourth heat transfer rate to the water flow using the second subcooler.

15. The method of claim 14 , further comprising evaporating the first refrigerant in the first refrigerant circuit using a first evaporator, and evaporating the second refrigerant in the second refrigerant circuit using a second evaporator.

16. The method of claim 15 , further comprising receiving waste heat from a chiller system using at least one of the first evaporator and the second evaporator.