Ampworth calculators

Work out which ENA connection procedure a domestic installation of solar panels, batteries or both falls under: connect first and notify the distribution network operator within 28 days, or apply and wait for approval before anything is connected. The rules are the ENA's engineering recommendations, not MCS documents: EREC G98 for small installations, EREC G99 for everything larger, and EREC G100

Calculate the sound pressure level an air source heat pump produces at an assessment position, and whether it meets the 37 dB(A) permitted development noise limit, using the method in MCS 020. The formula is Lp = Lw + 10 log(Q / 4.pi.r^2) - Ab. Lw is the A-weighted sound POWER level of the unit from its product fiche, energy label or the MCS product database. This is not the sound pressure level

Compare what a household spends heating on its current fuel with what the same heat would cost from a heat pump. The heat demand is worked out from the household's own metered fuel use, not from a model, because a year of bills describes a particular house far better than any estimate of it. Supply the annual fuel use in the fuel's own unit (kWh for gas and electricity, litres for oil and LPG, ki

Estimate the heat pump a UK house needs, and what it would cost to run against the fuel it burns now. IMPORTANT: MIS 3005-D requires a heat pump to be sized from a room-by-room heat loss calculation to BS EN 12831, and nothing here replaces that. Say so whenever you report a result from this, and point the user at the room-by-room calculation. What the figure is for is checking whether a size som

Work out the daily hot water demand of a dwelling and the size of cylinder a heat pump needs, using the formula in MIS 3005-D 3.5.2 and the BS 6700 guidance reproduced in MGD 007. The demand is 45 litres a day for each of N, where N is the greater of the number of bedrooms plus one and the number of people actually living there. For a new build, where occupancy is unknown, the bedroom count is us

Lists every calculator on this server, with the standard behind it and whether it is the whole-system sizing calculator or one of the single-method ones, plus the reference data a caller needs to build a valid request: the compass directions and their orientations, the shading descriptions, the twenty-five solar postcode zones, the eight heat pump design locations with their design temperatures, t

Work out the flow temperature a heat pump must produce to heat a room through a given radiator, and the resulting MCS Heat Emitter Guide star rating, following section 4 of MGD 007. This is the calculation that decides whether a heat pump will be cheap or expensive to run. A heat pump's efficiency falls as the water temperature rises, by roughly two to three per cent per degree, and the temperatu

Calculate the design heat loss of a single room in watts, following BS EN 12831 as MIS 3005-D applies it. This is the figure a heat pump is sized from and the figure the radiator in that room must be able to deliver. BS EN 12831 is a room-by-room method. Run this once for each heated room and add the results; sizing a heat pump from floor area alone is what produces the oversized installations th

Estimate the annual AC electricity output of a UK solar photovoltaic system, in kWh, using the standard estimation method that MIS 3002 requires every MCS certified installer to use. The method is: annual output = kWp x Kk x SF, where Kk is read from the MCS irradiance dataset for the site's postcode zone, roof pitch and orientation, and SF is a shade factor between 0 and 1. Supply the postcode

Estimate what proportion of a domestic solar PV system's annual output is consumed in the house and what proportion is exported, using the lookup tables in MGD 003. The tables are not a model. They come from half-hourly monitoring of real British households by Loughborough University, with battery behaviour modelled on top, so they carry the real shape of domestic demand: a peak before the sun is

Convert a completed MCS sunpath shading assessment into a shade factor, using the procedure in MGD 005. The MCS sunpath chart is divided into 84 segments, each worth one per cent of the year's useful irradiance. An assessor stands at the middle of where the array will go, plots what blocks the horizon onto the chart, and counts the segments covered. This tool takes that count and returns 1 minus

Work out the solar PV system a UK home needs: the capacity in kWp, the number of panels, the battery to go with it, and what it would do to the electricity bill. This runs the MCS arithmetic backwards. The other solar calculators here each answer one question about a system somebody has already specified. This one starts from what a household uses and arrives at the system that covers it, which i