SAV Energy Centres based on LoadTracker 15G combined heat and power have been specified for town developments, luxury flats, council estates and sheltered housing. Carbon savings of around 20% can be expected by using CHP in housing developments, with appreciable cost savings arising from the substitution of grid supplies by site-based generation.
SAV’s assessments of potential are of particular value for CHP in housing developments. The number of 15G units is chosen to produce the best match with the DHW and heating loads expected at the site. This is in contrast to hospitals and HM Prisons, for example, where demand tends to be far greater.
Regardless of the format of available raw load data, SAV can identify any items outstanding and make assumptions where necessary to deliver a complete CHP project assessment. Although SAV staff members are not accredited under SAP (Standard Assessment Procedure, as used for housing projects), full information relating to the CHP element is made freely available to whichever office is tasked to evaluate the project under SAP.
With primary flows of say, 80C from a centralized central boiler house, FlatStation HIUs provide the LTHW interface at each dwelling. The Danfoss FlatStation range has plate heat exchangers to provide instantaneous DHW, with accurate temperature control regardless of flow.
Direct type FlatStations are recommended where primary head is sufficient for heating circuits. Alternatively, indirect versions provide a hydraulic break between the primary and circulated secondary circuits. Where thermostatic valves are called for, optimum operation would be secured by controlling the differential pressure between upsteam / downstream piping.
To simplify hot water arrangements to each dwelling, FlatStations can be fitted with a DHW distribution manifold (see above, far right illustration). A parallel BCW manifold keeps piping very compact, as most of the line runs are shared.
Buffer vessels are used to meet DHW demand peaks. SAV can help with buffer vessel sizing, taking account of FlatStation HIU rating, coincidence factors and back-up gas boiler requirements.
Energy usage by residents of district heating schemes must be individually tracked to enable accurate billing. SAV Watchman helps property management companies to monitor such usage, observe results in real time via downloads and generate automatic billing to tenants or owner occupiers. Pre-payment meters can be offered where expected occupant profile suggests this would be appropriate.