Buildings can use 30% less electricity and reduce electrical maximum demand by up to 50% - simply by optimising the control of existing plant & equipment. That is smart building energy modelling!

Planning

Energy Planning Workshop

Buildings Evolved typically engage in an energy planning workshop prior to developing building energy models, controls simulation or developing reference designs. Our team is comprised of technologists and engineers that have the experience and capability to conduct design reviews of existing designs or as-built drawings.

We seek to:

• obtain updated models, renders and drawings from architects;
• obtain updated schematics, specifications and other documentation from core consulting engineer;
• discuss currently proposed solutions;
• update project requirements, goals and ambitions;
• identify issues and areas of improvement;
• scope potential development work; then
• gather and provide design feedback.

Smart Building Energy Modelling

BEM: Building System Analysis

Using updated architectural models incorporating works completed during the concept design phase, we begin the process of a Building System Analysis in conjunction with the building services engineers (mechanical, electrical, hydraulic, building envelope).

This phase commences when final architectural massing and programming is completed and covers the following metrics:

• energy use, disaggregated (heating, cooling, lighting, plug loads, fans, pumps);
• energy cost, by end use and utility;
• peak heating and cooling loads for the building;
• worst performing HVAC zones;
• energy use intensity; and
• GHG emissions & intensity.

Building Systems

We lead an energy workshop with the developer, architects & building services engineers to outline the results of completed concept design modelling with the intent of providing design parameters and to set a direction for the design development and (later) tendering process.

The focus of analysis for Building System Analysis is on the following building envelope components:

• wall R value (resistance to heat flow);
• wall interface heat loss;
• fenestration U value (heat flow through a given area) including solar heat gain and visible transmittance;
• floor & roof thermal performance;
• lighting load, modelling 2 different lux levels for sensitivity testing;
• plug load thermal load;
• HVAC systems (typically min 2 types such as air-based heating & cooling versus radiant heating & cooling);
• domestic hot water;
• energy generation and storage solutions;
• efficiency of mechanical systems including resistive loads, air-sourced heat-pumps, water-source heat pumps, chiller COP/nameplate capacity, boiler COP/nameplate, fans/pump/motor efficiencies, variable speed drives, heat recovery/heat exchange system efficiency; and
• specialised energy use cases: data centres, refrigeration, dehumidification, clinical, research labs et cetera.

Deliverables

The intent of this process to inform design and provide a level of co-ordination for the successful delivery of the developer’s strategy for energy systems within the project. This is achieved by providing input during design development to ensure that energy related design considerations are factored into decision making processes.

Report

A smart Building System Analysis summary report, incorporating the above requirements. The report includes:

• building name & location;
• modelling software used;
• occupancy type (apartment, aged care, over 50s, commercial, retail, supermarket, office et cetera);
• gross floor area/net lettable area;
• energy use summary report, broken down to different energy sources and energy uses, including generation and storage (thermal & chemical);
• energy use intensity (EUI);
• electrical maximum demand (and gas, if a component);
• mechanical, electrical, building envelope and occupancy schedules;
• window-to-wall ratio, fenestration-to-wall ratio (including doors);
• air leakage rate;
• lighting level intensity and use cases to calculate lighting load;
• EEO section, as detailed below;
• Rapid Cost Assessment, as detailed below; and
• provide a summary and list of recommendations along with proof of data-driven decision making.

Focus on energy efficiency opportunities (EEO):

• identify and list a range of EEOs from the design development process
• nominate three EEOs to run as what-if scenarios in the RCA; and
• EEOs that focus on operational modes and consequent reduction in equipment life-cycle replacement costs will be favoured for analysis.

Use of Rapid Cost Assessment to:

• define network tariffs, retail tariffs, embedded network tariffs;
• quantify the financial benefit versus the reference design using NPV and BCR;
• incorporate capex and opex costs, including equipment replacement based figures from BEM/BSA;
• provide a full cash summary over 50 years;
• GHG emissions and GHG intensity from grid (interval emissions intensity from scope 2 sources); and
• provide comparative analysis of three EEOs against the baseline design incorporating capex, opex and life-cycle replacement costs.

Rapid Cost Assessment

Capability Overview

Find the optimum mix of energy generation, storage and demand using a high-level data-driven approach. Load the ground truth data from NEM12 or CSV, then ‘mutate’ or modify historical data to simulate what-if addition/subtraction of energy related systems including:

System Sizing

• solar PV system size increase;
• battery peak lopping & arbitrage; and
• battery FCAS.

Control Strategies

• HVAC load-shifting (pre-heat/pre-cool);
• ventilation night-purge;
• energy consumption reduction/increase; and
• demand reduction/increase.
• adding an embedded network;

Financial Impacts

• load profiles (ground truth to what-if);
• discount cash rate;
• inflation;
• cap-ex (incl equipment replacement costs);
• op-ex;
• tariff change (network/retail);
• annual credits; and
• power factor.

Meaningful Reports for Decision Makers

Compare what-if scenarios to the ground-truth using:

• 15 & 50 year Benefit Cost Ratio (BCR);
• 15 & 50 year Net Present Value (NPV); and
• 50-year discount cash flow.

Do More

Physics-based Controls Simulation

Modelica control simulations coupled with building physics models allow advanced full-building simulations to LEED certified requirements. This increasingly useful in modelling the complex energy balance within new buildings.

While building physics models principally help with understanding heating and cooling loads and their impact upon electrical consumption and demand, controls simulations provide the next level in validation of more complex systems now found in many developments.

Understanding the relationship between building physics coupled with occupancy and use case is complex enough at scale. Now we seek to understand the interaction of building physics with energy generation, storage (chemical & thermal), demand flexibility and heat recovery. To properly understand the interactions between the energy systems and the building, a control simulation is required.

Controls simulations are relatively new for the Australian market but has been commonplace in the USA with the LEED certified building program. Now industry is driving demand, more from an engineering than a sustainability perspective, as had been the case in the past.