The Waterfront Project: A Collaboration between FirstLight Energy and Hysopt

The Waterfront Project in Canada

After installing two Heat Recovery Chillers (HRCs) at Granville building, the facility steam usage was reduced by approximately, 50%. The owner, as part of their sustainability goals, wanted to expand the potential of the HRCs. FirstLight, with Hysopt, conducted a study to explore different heat sources opportunities to improve the existing system performance.

FirstLight proposed connecting Granville to Burrard, a nearby building with excess heat and, refurbishing a decommissioned 400,000 gallons thermal storage. Hysopt’s Digital Twin technology assessed feasibility, determining the best connection approach and whether additional heat from Howe might be needed.

The Waterfront Project explores the feasibility of energy recuperation among three high-rise buildings in Vancouver (Canada), and demonstrates how Hysopt helped quantify energy-saving opportunities and optimise HVAC system performance. 

Objective

1. Investigate recent HRCs inclusion and identify optimisation potential for the Granville building
2. Evaluate energy recuperation potential using thermal energy storage (TES) between three buildings
3. Investigation in required pipe sizes for the pipes connected to the large TES

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Buildings:

1. Granville: Existing HVAC with HRCs heat pumps
2. Burrard: Cooling loads with excess condenser loop capacity
3. Howe: Potential addition to optimise performance

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The Hysopt Simulator

The Hysopt Simulator is a dynamic simulation software that replicates the real behaviour of HVAC systems using thermodynamic formulas. By integrating real hydraulic components and system controls, the Digital Twin provides insights into system performance and identifies optimisation opportunities. Key features include:

• Dynamic Load Simulations: Accurate modelling of heating and cooling demands over a full year by inclusion of BEMS trend data
• Control Integration: Simulation of BEMS controls and operational scenarios
• Feasibility Analysis: Quantification of potential energy savings and carbon reductions of proposed design

This digital representation enables data-driven decision-making, ensuring optimal system configurations and investment planning.

Granville Heat Recovery System

In order to reduce carbon emissions, HRCs were installed inthe Granville building. These units currently cover a part of the heating and cooling load of the building. The additional heating and cooling load is covered by steam fed heat exchangers and chillers respectively.

In the Hysopt model, it was seen that the HRCs have the correct capacity, but aren’t able to deliver heating due to a lack of cooling demand in peak heating conditions. Since HRCs require simultaneous heating and cooling loads in order to operate, the heat output of these HRCs is limited by the available cooling demand in the winter.

In order to increase the load share of the HRCs and to limit the load share of the steam-fed heat exchangers, extra cooling demand should be created in winter to allow extended operating hours of the heat recovery units.

The Digital Twin makes it possible to investigate the following solutions:

• Optimisation of existing induction loop to create additional cooling loads
• Inclusion of a large existing 400,000 gallon water tank for thermal energy storage
• Connection to Howe building for additional heat sources

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Steam Reduction Potential with Thermal Energy Storage

By visualisation of the BEMS trends in Hysopt, a significant energy saving opportunity was discovered. By recuperating a part of the Burrard building condenser loads which are currently rejected by a cooling tower, we can charge the TES in winter to cover the additional cooling demand created by the TES integration in Granville.

Since 250 Howe has additional spare heating capacity, the Hysopt model was able to investigate if Howe building should be connected to the TES as well to maximise HRC operation in Granville. As a result, the Hysopt model verified that Burrard alone has sufficient spare condenser loop capacity available to maximise HRC heat injection.

TES Integration Benefits:

• A 400,000-gallon TES allows energy exchange among buildings - recuperation of Burrard condenser capacity
• Potential steam reduction: 63-71%
• Carbon emissions reduction: 63-70%

Enhanced HRU Operation:

• Adding an extra HRC module at Granville could further cut steam usage and emissions by 81%

In order to achieve the condenser heat recuperation, the required HX capacity, flow rates and required pipe sizes were designed by use of the Hysopt software. The sized capacities will determine the amount of extra cooling load than can be generated and more carbon emissions and steam consumption that can potentially be avoided. The decision for increasing the HX schedules and pipe sizes will result in an additional CAPEX-investment. This trade-off was objectified by the Pareto Analysis in Hysopt.

1. Steam cost reduction:

• Annual savings range from $108k to $136k

2. Electricity cost impact:

• Increased HRC and chiller use raises electricity costs slightly 

3. CO₂ emissions:

• Reduction potential around 520 tonnes/year

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Conclusion

The study demonstrates that integrating TES and optimizing HVAC configurations significantly improves energy efficiency and reduces operational costs up to $136k per year. It also aligns with their sustainability goals, saving up to 520 tonnes of CO₂ per year. Further steps include finalising CAPEX estimates and detailed TES implementation planning.