The Vital Link Between Boiler, Building and the Environment
Medium to large size buildings - The facts about heating efficiency.
A €1 million EU Research Programme contracted to BRE (Watford) and completed in 2001 revealed that all medium to large size buildings are “overheated” for most, if not all, of the heating season.
In extreme cases of overheating or heat wastage, which are mainly generated through the absence of good building controls, the problem is obvious. Occupants feel they have to open windows sometimes even in winter.
On the other hand, when your building is responding comfortably to new or well-maintained high quality and programmable building controls you probably consider that your heating is as efficient as it can possibly be. In reality, although you can’t sense it, it is not and your building is still being overheated!
You may even have a sophisticated Building Management System installed at great expense by an expert systems programmer but there is an ‘efficiency gap’ in the control strategies of such systems. Boilers, in principle, need to provide the correct amount of heat energy to balance building heat losses and gains under given set point and weather conditions. What is not understood is that ‘state of the art’ installed building controls – even those produced and sometimes maintained by prominent global suppliers such as TAC, Siemens, Honeywell (Trend) and Johnson - are falling short of the ability to dynamically balance building heat gains and losses through their currently embedded or programmed control strategies.
The two main contributors to heat wastage in buildings, whether poorly or well controlled, are:
- Boiler set-point temperatures are nearly always unnecessarily high even if compensated for demand.
- Control decisions to change boiler temperatures, sequencing or the mixing of primary temperatures to achieve lower secondary temperatures are made as a result of inside and outside temperature differences and not building heat losses and gains. Every building has its own heat transfer profile and heat “inflows” have to be dynamically reconciled with “outflows” for good energy control. This individual balancing is needed to prevent buildings being over-heated
Computer modelling and 4 years experience in the field has proved that the Fuelstretcher patented technology achieves this balance with outstanding results in heating energy savings across a wide spectrum of medium to large size buildings - See Research and Case Studies.
Intelligent programmable building controls are being installed around the world at this moment with weather compensation /demand strategies that support the use of excessive boiler energy. The first Fuelstretcher controller was patented and developed to exploit this “gap” in “ Best Practice” for building energy control.
How does the Fuelstretcher fill this “gap” in building control intelligence?
Existing control systems, at best, make use of inside and outside sensor temperature networking to drive controls for more comfort. Correctly programmed Building Management Systems and even Weather Compensation Controllers, in conjunction with Constant and Variable Temperature controlled circuit controls, generally make good comfort control decisions. Such decisions in themselves, however, are not the best from a system efficiency standpoint. Although the Fuelstretcher observes the set points and demands of comfort controls it imposes a higher order of intelligence in terms of efficient and dynamic temperature control and sequence of boilers. Fuelstretcher intelligence is based on continuous development of a heat loss /heat gain profile as the building is affected by internal and external conditions over a 24 hour cycle.
It analyses the profile and then predicts and manages the efficient output of the heating system boilers on a continuous basis every day during occupancy for your complete heating season to eliminate wasted heat. This discipline is applied even if your building requires heating all year round for 24 hours per day.
Most importantly whilst your heating energy is being reduced your comfort control will, at worst, be unaffected and in many cases improved! It ensures an intelligent and accurate balancing of building heat gains and losses running up to, and during, daily occupancy of the building.
It also self-determines the point at which profiling is converted to boiler control and sequencing to provide the lowest primary temperatures to meet comfort demand set by the other building/comfort controls. This results in no excess heat or “ standing losses” being absorbed by heating system equipment or the building fabric or by the space itself due to overshoot of set points. Significant amounts of fuel are saved with this practice. As time passes, the Fuelstretcher accumulates its daily data, thus adding a refinement to its learning about the building’s heat loss/gain characteristics and tuning itself ever closer to the exact heating needs. No heat wastage and no building overheating.
The process of prediction, analysis, control and management of boilers is completely automatic and self-tuning once it is commissioned. There are no user controls needed except for an “override” switch for use during normal boiler maintenance schedules.