Generation of Electricity by Solar Panels

Generation of Electricity by Solar Panels

The following table shows the generation of electricity by the solar panels for each month in 2011 in units (kW.hours). It also gives the units exported. As we do not have an export meter these are defined to be half the units generated. The last column gives an estimate of the units saved (i.e. used by us and not actually exported). The numbers do not add up! This is because in the winter virtually all the units are generated over a very short period around midday - this may be used by the heat pump if it is running then. In the summer it is more likely that the electricity will be generated when it can be used (i.e. mornings and evenings), but even then it is difficult to use more than half the electricity generated. We maximised our usage in the summer by only running the heat pump for about an hour around midday, and also only using the washing machine and dish washer when we were exporting electricity. Overall we used about one third of the electricity we generated. The total saving was £1678 for the year although £108 of this was assigned to the heat pump (based on 13.17p per unit).

MonthUnits generatedUnits exportedUnits Saved
January53.326.716
February75.137.628
March296.2148.186
April494.7247.2131
May509.0254.5240
June435.3217.7149
July446.7223.4240
August338.1194.1271
September305.3152.7150
October217.6108.860
November84.142.141
December69.134.638
Totals337416871317
Value£1453£52£173

This table is for 2012. The total saving was £1600 for the year although £125 of this was assigned to the heat pump (based on 14.36p per unit).

MonthUnits generatedUnits exportedUnits Saved
January95.847.951
February149.174.658
March333.4166.799
April348.3174.2116
May414.7207.4149
June373.5186.8235
July395.0197.5189
August399.3199.7177
September325.9163.0113
October146.373.265
November102.351.240
December62.731.334
Totals314615731326
Value£1362£48£190

This table is for 2013. The total saving was £1714 for the year although £125 of this was assigned to the heat pump (based on 14.36p per unit).

MonthUnits generatedUnits exportedUnits Saved
January55.727.838
February113.456.766
March164.682.368
April383.0191.5107
May424.1212.1198
June432.0216.0216
July529.8264.5255
August439.0219.5265
September257.7128.9166
October143.671.853
November88.344.123
December64.532.339
Totals309615481494
Value£1449£51£214

This table is for 2014. The total saving was £1885 for the year although £121 of this was assigned to the heat pump. Note that a new import meter was fitted in July and the cost of electricity dropped to £0.1239 per unit in the same month (about the same as in March 2011).

MonthUnits generatedUnits exportedUnits Saved
January76.238.153
February131.365.679
March312.0156.0111
April371.6185.8111
May411.0205.5213
June485.6242.8259
July519.4259.7263
August393.3196.7226
September294.8147.4178
October150.375.181
November76.438.229
December69.734.948
Totals3386.01643.31642
Value£1627£55£203

This table is for 2015. The total saving was £1818 for the year although £140 of this was assigned to the heat pump. Note that the cost of electricity dropped to £0.1216 per unit in April (about the same as in March 2011). By the end of the year the solar panels must have produced as much energy as was used in their construction, transportation and installation so they can be considered "green" from now.

MonthUnits generatedUnits exportedUnits Saved
January84.242.167
February111.455.766
March275.9138.0111
April455.2227.6240
May434.5217.3238
June503.0251.5265
July417.3207.8273
August332.3166.2215
September321.4160.7203
October161.480.749
November49.924.96
December32.916.415
Totals3179.41589.71748
Value£1552£54£212

This table is for 2016. The total saving was £1804 for the year although £122 of this was assigned to the heat pump (based on 12.16p per unit).

MonthUnits generatedUnits exportedUnits Saved
January61.730.948
February137.068.5105
March271.7135.9120
April381.8190.9135
May467.8233.9241
June342.6171.3146
July457.2228.6240
August445.2222.6230
September258.0129.0177
October178.589.379
November93.846.931
December60.930.539
Totals3156.21578.11588
Value£1557£54£193

This table is for 2017. The total saving was £? for the year although £? of this was assigned to the heat pump (based on 14.03p per unit).

MonthUnits generatedUnits exportedUnits Saved
January80.840.461
February91.345.642
March263.7131.979
April430.1215.0172
May405.1202.6200
June484.2242.1216
July436.7218.3233
August412.1206.1209
September253.7126.9143
October140.470.250
November96.448.239
December60.930.539
Totals3156.21578.11588
Value£1557£54£193