1 Energy Performance Certificates (EPCs)

Apart from a few exempted buildings, a dwelling must have an EPC when constructed, sold or let. This means that over time we will have an EPC for an increasing number of properties and we should already have EPCs for all rented properties.

EPCs are not necessarily up to date. For example if a property has not been sold or let since a major upgrade, the effects of that upgrade may not be visible in the data.

Further reading:

check what feeds in automatically e.f. RHI installs etc

We have to assume the data we have is the current state of play for these dwellings.

2 Southampton EPCs

df <- path.expand("~/data/EW_epc/domestic-E06000045-Southampton/certificates.csv")
allEPCs_DT <- data.table::fread(df)
## Warning in require_bit64_if_needed(ans): Some columns are type 'integer64' but package bit64 is
## not installed. Those columns will print as strange looking floating point data. There is no need to
## reload the data. Simply install.packages('bit64') to obtain the integer64 print method and print the
## data again.

The EPC data file has 91833 records for Southampton and 90 variables. We’re not interested in all of these, we want:

  • PROPERTY_TYPE: Describes the type of property such as House, Flat, Maisonette etc. This is the type differentiator for dwellings;
  • BUILT_FORM: The building type of the Property e.g. Detached, Semi-Detached, Terrace etc. Together with the Property Type, the Build Form produces a structured description of the property;
  • ENVIRONMENT_IMPACT_CURRENT: A measure of the property’s current impact on the environment in terms of carbon dioxide (CO₂) emissions. The higher the rating the lower the CO₂ emissions. (CO₂ emissions in tonnes / year) NB this is a categorised scale calculated from CO2_EMISSIONS_CURRENT;
  • ENERGY_CONSUMPTION_CURRENT: Current estimated total energy consumption for the property in a 12 month period (kWh/m2). Displayed on EPC as the current primary energy use per square metre of floor area. Nb: this covers heat and hot water (and lightng?)
  • CO2_EMISSIONS_CURRENT: CO₂ emissions per year in tonnes/year NB: this is calculated from the modelled kWh energy input using (possibly) outdated carbon intensity values;
  • TENURE: Describes the tenure type of the property. One of: Owner-occupied; Rented (social); Rented (private).

We’re also going to keep:

  • WIND_TURBINE_COUNT: Number of wind turbines; 0 if none;
  • PHOTO_SUPPLY: Percentage of photovoltaic area as a percentage of total roof area. 0% indicates that a Photovoltaic Supply is not present in the property;
  • TOTAL_FLOOR_AREA: The total useful floor area is the total of all enclosed spaces measured to the internal face of the external walls, i.e. the gross floor area as measured in accordance with the guidance issued from time to time by the Royal Institute of Chartered Surveyors or by a body replacing that institution. (m²) - to allow for the calculation of total energy demand;
  • POSTCODE - to allow linkage to other datasets
  • LOCAL_AUTHORITY_LABEL - for checking

These may indicate ‘non-grid’ energy inputs.

If an EPC has been updated or refreshed, the EPC dataset will hold multiple EPC records for that property. We will just select the most recent.

# select just these vars
dt <- allEPCs_DT[, .(BUILDING_REFERENCE_NUMBER, LMK_KEY, LODGEMENT_DATE, PROPERTY_TYPE, BUILT_FORM,
                ENVIRONMENT_IMPACT_CURRENT, ENERGY_CONSUMPTION_CURRENT, CO2_EMISSIONS_CURRENT, TENURE,
                PHOTO_SUPPLY, WIND_TURBINE_COUNT, TOTAL_FLOOR_AREA, 
                POSTCODE, LOCAL_AUTHORITY_LABEL)]

# select most recent record within BUILDING_REFERENCE_NUMBER - how?
# better check this is doing so
setkey(dt,BUILDING_REFERENCE_NUMBER, LODGEMENT_DATE) # sort by date within reference number
sotonUniqueEPCsDT <- unique(dt, by = "BUILDING_REFERENCE_NUMBER",
                   fromLast = TRUE) # which one does it take?

test1 <- allEPCs_DT[, .(min1 = min(LODGEMENT_DATE), 
                        nRecords = .N), 
                    keyby = .(BUILDING_REFERENCE_NUMBER)]

test2 <- sotonUniqueEPCsDT[, .(min2 = min(LODGEMENT_DATE)), 
                           keyby = .(BUILDING_REFERENCE_NUMBER)]
t <- test1[test2]
t[, diff := min2 - min1]

summary(t[nRecords > 1]) # diff is always >= 0 so min2 (after unique) is always > min1
##  BUILDING_REFERENCE_NUMBER      min1               nRecords          min2                 diff     
##  Min.   : 0.000e+00        Min.   :2008-10-01   Min.   :2.000   Min.   :2008-10-10   Min.   :   0  
##  1st Qu.:1.224e-314        1st Qu.:2009-04-01   1st Qu.:2.000   1st Qu.:2014-08-22   1st Qu.: 745  
##  Median :2.473e-314        Median :2010-03-01   Median :2.000   Median :2018-02-19   Median :1960  
##  Mean   :2.463e-314        Mean   :2011-04-19   Mean   :2.179   Mean   :2017-01-05   Mean   :2088  
##  3rd Qu.:3.703e-314        3rd Qu.:2013-03-18   3rd Qu.:2.000   3rd Qu.:2019-04-30   3rd Qu.:3643  
##  Max.   :4.940e-314        Max.   :2020-06-30   Max.   :9.000   Max.   :2020-06-30   Max.   :4279
# confirms fromLast = TRUE has selected the most recent within BUILDING_REFERENCE_NUMBER

skimr::skim(sotonUniqueEPCsDT)
## Warning: Couldn't find skimmers for class: integer64; No user-defined `sfl` provided. Falling back
## to `character`.
Table 2.1: Data summary
Name sotonUniqueEPCsDT
Number of rows 71600
Number of columns 14
_______________________
Column type frequency:
character 7
Date 1
numeric 6
________________________
Group variables None

Variable type: character

skim_variable n_missing complete_rate min max empty n_unique whitespace
BUILDING_REFERENCE_NUMBER 0 1 17 21 0 71600 0
LMK_KEY 0 1 29 34 0 71600 0
PROPERTY_TYPE 0 1 4 10 0 5 0
BUILT_FORM 0 1 8 20 0 7 0
TENURE 0 1 0 16 1988 6 0
POSTCODE 0 1 8 8 0 5107 0
LOCAL_AUTHORITY_LABEL 0 1 11 11 0 1 0

Variable type: Date

skim_variable n_missing complete_rate min max median n_unique
LODGEMENT_DATE 0 1 2008-10-01 2020-06-30 2014-10-20 4132

Variable type: numeric

skim_variable n_missing complete_rate mean sd p0 p25 p50 p75 p100 hist
ENVIRONMENT_IMPACT_CURRENT 0 1.00 62.56 15.73 1.0 52.0 63.0 73 115.00 ▁▂▇▅▁
ENERGY_CONSUMPTION_CURRENT 0 1.00 262.90 140.55 -184.0 173.0 233.0 327 1597.00 ▃▇▁▁▁
CO2_EMISSIONS_CURRENT 0 1.00 3.16 1.94 -1.8 1.8 2.8 4 77.00 ▇▁▁▁▁
PHOTO_SUPPLY 38595 0.46 0.59 5.12 0.0 0.0 0.0 0 100.00 ▇▁▁▁▁
WIND_TURBINE_COUNT 5556 0.92 0.00 0.03 -1.0 0.0 0.0 0 1.00 ▁▁▇▁▁
TOTAL_FLOOR_AREA 0 1.00 72.97 34.93 0.0 49.0 69.0 87 1353.68 ▇▁▁▁▁

As we can see that we have 71600 unique property reference numbers. We can also see some strangeness. In some cases we seem to have:

  • negative energy consumption;
  • negative emissions;
  • 0 floor area

This is not surprising since the kWh/y and TCO2/y values are estimated using a model but before we go any further we’d better check if these are significant in number.

2.1 Check ‘missing’ EPC rates

We will do this mostly at MSOA level as it allows us to link to other MSOA level datasets. Arguably it would be better to do this at LSOA level but…

First we’ll use the BEIS 2018 MSOA level annual electricity data to estimate the number of meters (not properties) - some addresses can have 2 meters (e.g. standard & economy 7). This is more useful than the number of gas meters since not all dwellings have mains gas but all have an electricity meter.

beisElecDT <- data.table::fread("~/data/beis/MSOA_DOM_ELEC_csv/MSOA_ELEC_2018.csv")
sotonElecDT <- beisElecDT[LAName %like% "Southampton", .(nElecMeters = METERS,  
                                                         beisElecMWh = KWH/1000, 
                                                         MSOACode, LAName)
                          ]


beisGasDT <- data.table::fread("~/data/beis/MSOA_DOM_GAS_csv/MSOA_GAS_2018.csv")
sotonGasDT <- beisGasDT[LAName %like% "Southampton", .(nGasMeters = METERS,  
                                                         beisGasMWh = KWH/1000, 
                                                         MSOACode)]

setkey(sotonElecDT, MSOACode)
setkey(sotonGasDT, MSOACode)
sotonEnergyDT <- sotonGasDT[sotonElecDT]
sotonEnergyDT[, beisEnergyMWh := beisElecMWh + beisGasMWh]
#head(sotonEnergyDT)

Next we’ll check for the number of households reported by the 2011 Census.

would be better to use dwellings but this gives us tenure

#censusDT <- data.table::fread(path.expand("~/data/"))
# IMD ----
deprivationDT <- data.table::fread(path.expand("~/data/census2011/2011_MSOA_deprivation.csv"))
deprivationDT[, totalHouseholds := `Household Deprivation: All categories: Classification of household deprivation; measures: Value`]
deprivationDT[, MSOACode := `geography code`]
setkey(deprivationDT, MSOACode)
setkey(sotonElecDT, MSOACode)
# link LA name from Soton elec for now
sotonDep_DT <- deprivationDT[sotonElecDT[, .(MSOACode, LAName)]]
sotonDep_DT[, nHHs_deprivation := `Household Deprivation: All categories: Classification of household deprivation; measures: Value`]

#sotonDep_DT[, .(nHouseholds = sum(totalHouseholds)), keyby = .(LAName)]

# census tenure ----
sotonTenureDT <- data.table::fread(path.expand("~/data/census2011/2011_MSOA_householdTenure_Soton.csv"))

sotonTenureDT[, census2011_socialRent := `Tenure: Social rented; measures: Value`]
sotonTenureDT[, census2011_privateRent := `Tenure: Private rented; measures: Value`]
sotonTenureDT[, census2011_ownerOccupy := `Tenure: Owned; measures: Value`]
sotonTenureDT[, census2011_other := `Tenure: Living rent free; measures: Value`]
sotonTenureDT[, MSOACode := `geography code`]

sotonTenureDT[, hhCheck := census2011_socialRent + census2011_privateRent + census2011_ownerOccupy + census2011_other]
sotonTenureDT[, nHHs_tenure := `Tenure: All households; measures: Value`]

# summary(sotonTenureDT[, .(hhCheck, nHHs_tenure)])
# might not quite match due to cell perturbation etc?

# join em ----
setkey(sotonDep_DT, MSOACode)
setkey(sotonTenureDT, MSOACode)

sotonCensus2011_DT <- sotonTenureDT[sotonDep_DT]

t <- sotonCensus2011_DT[, .(sum_Deprivation = sum(nHHs_deprivation),
                            sum_Tenure = sum(nHHs_tenure)), keyby = .(LAName)]
kableExtra::kable(t, caption = "Census derived household counts")
Table 2.2: Census derived household counts
LAName sum_Deprivation sum_Tenure
Southampton 98254 98254

That’s lower (as expected) but doesn’t allow for dwellings that were empty on census night.

# Postcodes don't help - no count of addresses in the data (there used to be??)
# but we can use it to check which Soton postcodes are missing from the EPC file
soPostcodesDT <- data.table::fread(path.expand("~/data/UK_postcodes/NSPL_AUG_2020_UK/Data/multi_csv/NSPL_AUG_2020_UK_SO.csv"))

soPostcodesDT <- soPostcodesDT[is.na(doterm)] # keep current

sotonPostcodesDT <- soPostcodesDT[laua == "E06000045"] # keep Southampton City

sotonPostcodesReducedDT <- sotonPostcodesDT[, .(pcd, pcd2, pcds, laua, msoa11, lsoa11)]

sotonPostcodesReducedDT[, c("pc_chunk1","pc_chunk2" ) := tstrsplit(pcds, 
                                                                   split = " "
                                                                   )
                        ]
sotonPostcodesReducedDT[, .(nEPCs = .N), keyby = .(pc_chunk1)]
##    pc_chunk1 nEPCs
## 1:      SO14   849
## 2:      SO15  1176
## 3:      SO16  1328
## 4:      SO17   443
## 5:      SO18   859
## 6:      SO19  1164

We should not have single digit postcodes in the postcode data - i.e. S01 should not be there (since 1993). Southampton City is unusual in only having double digit postcodes.

# EPC
# set up counters
sotonUniqueEPCsDT[, epcIsSocialRent := ifelse(TENURE == "rental (social)", 1, 0)]
sotonUniqueEPCsDT[, epcIsPrivateRent := ifelse(TENURE == "rental (private)", 1, 0)]
sotonUniqueEPCsDT[, epcIsOwnerOcc := ifelse(TENURE == "owner-occupied", 1, 0)]
sotonUniqueEPCsDT[, epcIsUnknownTenure := ifelse(TENURE == "NO DATA!" |
                                          TENURE == "" , 1, 0)]
# aggregate EPCs to postcodes
sotonEpcPostcodes_DT <- sotonUniqueEPCsDT[, .(nEPCs = .N,
                                              sumEPC_tCO2 = sum(CO2_EMISSIONS_CURRENT, na.rm = TRUE),
                                     n_epcIsSocialRent = sum(epcIsSocialRent, na.rm = TRUE),
                                     n_epcIsPrivateRent = sum(epcIsPrivateRent, na.rm = TRUE),
                                     n_epcIsOwnerOcc = sum(epcIsOwnerOcc, na.rm = TRUE),
                                     n_epcIsUnknownTenure = sum(epcIsUnknownTenure, na.rm = TRUE),
                               sumEpcMWh = sum(ENERGY_CONSUMPTION_CURRENT* TOTAL_FLOOR_AREA)/1000), # crucial as ENERGY_CONSUMPTION_CURRENT = kWh/m2
                           keyby = .(POSTCODE, LOCAL_AUTHORITY_LABEL)]

sotonEpcPostcodes_DT[, c("pc_chunk1","pc_chunk2" ) := tstrsplit(POSTCODE, 
                                                                   split = " "
                                                                   )
                        ]
sotonEpcPostcodes_DT[, .(nEPCs = .N), keyby = .(pc_chunk1)]
##    pc_chunk1 nEPCs
## 1:      SO14   601
## 2:      SO15   960
## 3:      SO16  1245
## 4:      SO17   403
## 5:      SO18   776
## 6:      SO19  1122
# check original EPC data for Soton - which postcodes are covered?
allEPCs_DT[, c("pc_chunk1","pc_chunk2" ) := tstrsplit(POSTCODE, 
                                                                   split = " "
                                                                   )
                        ]
allEPCs_DT[, .(nEPCs = .N), keyby = .(pc_chunk1)]
##    pc_chunk1 nEPCs
## 1:      SO14 14213
## 2:      SO15 17855
## 3:      SO16 20270
## 4:      SO17  8446
## 5:      SO18 10661
## 6:      SO19 20388

It looks like we have EPCs for each postcode sector which is good.

# match the EPC postcode summaries to the postcode extract
sotonPostcodesReducedDT[, POSTCODE_s := stringr::str_remove(pcds, " ")]
setkey(sotonPostcodesReducedDT, POSTCODE_s)
sotonPostcodesReducedDT[, MSOACode := msoa11]
message("Number of postcodes: ",uniqueN(sotonPostcodesReducedDT$POSTCODE_s))
## Number of postcodes: 5819
sotonEpcPostcodes_DT[, POSTCODE_s := stringr::str_remove(POSTCODE, " ")]
setkey(sotonEpcPostcodes_DT, POSTCODE_s)
message("Number of postcodes with EPCs: ",uniqueN(sotonEpcPostcodes_DT$POSTCODE_s))
## Number of postcodes with EPCs: 5107
dt <- sotonEpcPostcodes_DT[sotonPostcodesReducedDT]

# aggregate to MSOA - watch for NAs where no EPCs in a given postcode
sotonEpcMSOA_DT <- dt[, .(nEPCs = sum(nEPCs, na.rm = TRUE), 
                          sumEPC_tCO2 = sum(sumEPC_tCO2, na.rm = TRUE),
                                        n_epcIsSocialRent = sum(n_epcIsSocialRent, na.rm = TRUE),
                                        n_epcIsPrivateRent = sum(n_epcIsPrivateRent, na.rm = TRUE),
                                        n_epcIsOwnerOcc = sum(n_epcIsOwnerOcc, na.rm = TRUE),
                                        n_epcIsUnknownTenure = sum(n_epcIsUnknownTenure, na.rm = TRUE),
                                        sumEpcMWh = sum(sumEpcMWh, na.rm = TRUE)
                                        ),
                                    keyby = .(MSOACode) # change name on the fly for easier matching
                                    ] 

#summary(sotonEpcMSOA_DT)

So we have some postcodes with no EPCs.

Join the estimates together at MSOA level for comparison. There are 32 MSOAs in Southampton.

# 32 LSOAs in Soton
# add deprivation
setkey(sotonEnergyDT, MSOACode)
setkey(sotonCensus2011_DT, MSOACode)
setkey(sotonEpcMSOA_DT, MSOACode)

sotonMSOA_DT <- sotonCensus2011_DT[sotonEnergyDT]
#names(sotonMSOA_DT)
sotonMSOA_DT <- sotonEpcMSOA_DT[sotonMSOA_DT]
#names(sotonMSOA_DT)

# add MSOA names from the postcode LUT

msoaNamesDT <- data.table::as.data.table(readxl::read_xlsx(path.expand("~/data/UK_postcodes/NSPL_AUG_2020_UK/Documents/MSOA (2011) names and codes UK as at 12_12.xlsx")))
msoaNamesDT[, MSOACode := MSOA11CD]
msoaNamesDT[, MSOAName := MSOA11NM]
setkey(msoaNamesDT, MSOACode)

sotonMSOA_DT <- msoaNamesDT[sotonMSOA_DT]

#names(sotonMSOA_DT)
t <- sotonMSOA_DT[, .(nHouseholds_2011 = sum(nHHs_tenure),
                      nElecMeters_2018 = sum(nElecMeters),
                      nEPCs_2020 = sum(nEPCs),
                      sumEPCMWh = sum(sumEpcMWh),
                  sumBEISMWh = sum(beisEnergyMWh),
                  sumEPC_tCO2 = sum(sumEPC_tCO2)
                  )]

kableExtra::kable(t, caption = "Comparison of different estimates of the number of dwellings and energy demand") %>%
  kable_styling()
Table 2.3: Comparison of different estimates of the number of dwellings and energy demand
nHouseholds_2011 nElecMeters_2018 nEPCs_2020 sumEPCMWh sumBEISMWh sumEPC_tCO2
98254 108333 71276 1286499 1276983 225568
nHouseholds_2011f <- sum(sotonMSOA_DT$nHHs_tenure)
nElecMeters_2018f <- sum(sotonMSOA_DT$elecMeters)
nEPCs_2020f <- sum(sotonMSOA_DT$nEPCs)

makePC <- function(x,y,r){
  # make a percent of x/y and round it to r decimal places
  pc <- round(100*(x/y),r)
  return(pc)
}

We can see that the number of EPCs we have is:

  • 72.5% of Census 2011 households
    • % of the recorded 2018 electricity meters

We can also see that despite having ‘missing’ EPCs, the estimated total EPC-derived energy demand is marginally higher than the BEIS-derived weather corrected energy demand data. Given that the BEIS data accounts for all heating, cooking, hot water, lighting and appliance use we would expect the EPC data to be lower even if no EPCs were missing…

sotonMSOA_DT[, dep0_pc := 100*(`Household Deprivation: Household is not deprived in any dimension; measures: Value`/nHHs_deprivation)]
sotonMSOA_DT[, socRent_pc := 100*(census2011_socialRent/nHHs_tenure)]
sotonMSOA_DT[, privRent_pc := 100*(census2011_privateRent/nHHs_tenure)]
sotonMSOA_DT[, ownerOcc_pc := 100*(census2011_ownerOccupy/nHHs_tenure)]

t <- sotonMSOA_DT[, .(MSOAName, MSOACode, nHHs_tenure,nElecMeters,nEPCs,
                      dep0_pc, socRent_pc, privRent_pc, ownerOcc_pc,sumEpcMWh, beisEnergyMWh )]

t[, pc_missingHH := makePC(nEPCs,nHHs_tenure,1)]
t[, pc_missingMeters := makePC(nEPCs,nElecMeters,1)]
t[, pc_energyBEIS := makePC(sumEpcMWh,beisEnergyMWh,1)]

kableExtra::kable(t[order(-pc_missingHH)], digits = 2, caption = "EPC records as a % of n census households and n meters per MSOA") %>%
  kable_styling()
Table 2.4: EPC records as a % of n census households and n meters per MSOA
MSOAName MSOACode nHHs_tenure nElecMeters nEPCs dep0_pc socRent_pc privRent_pc ownerOcc_pc sumEpcMWh beisEnergyMWh pc_missingHH pc_missingMeters pc_energyBEIS
Southampton 029 E02003577 4908 6734 5902 37.92 27.61 43.09 24.67 77239.37 47461.33 120.3 87.6 162.7
Southampton 023 E02003571 3040 3530 2958 47.96 20.23 56.97 21.48 47763.66 33485.69 97.3 83.8 142.6
Southampton 022 E02003570 3635 4142 3426 25.56 29.82 45.69 22.59 58314.50 49449.97 94.3 82.7 117.9
Southampton 017 E02003565 2563 2840 2403 48.81 11.63 57.24 28.95 42564.50 35191.63 93.8 84.6 121.0
Southampton 031 E02003579 3357 4460 3112 44.92 11.56 23.80 63.09 46142.79 47913.06 92.7 69.8 96.3
Southampton 013 E02003561 3181 3489 2663 39.80 19.68 44.73 33.98 49213.04 38430.85 83.7 76.3 128.1
Southampton 009 E02003557 2753 3103 2137 50.78 7.37 38.98 52.49 47035.21 42842.23 77.6 68.9 109.8
Southampton 020 E02003568 3820 3900 2959 50.08 4.53 50.92 42.93 53455.26 47024.09 77.5 75.9 113.7
Southampton 010 E02003558 2924 3222 2223 33.96 32.32 25.82 39.81 38646.22 34421.99 76.0 69.0 112.3
Southampton 021 E02003569 3527 3999 2671 40.71 15.00 38.28 44.32 46809.22 41380.67 75.7 66.8 113.1
Southampton 015 E02003563 3483 3818 2551 37.81 21.79 24.17 51.79 46440.94 39920.85 73.2 66.8 116.3
Southampton 027 E02003575 2808 2987 2028 29.59 51.14 8.23 37.64 36556.34 28941.46 72.2 67.9 126.3
Southampton 007 E02003555 3140 3763 2261 34.59 30.96 11.15 56.15 35182.76 40416.83 72.0 60.1 87.0
Southampton 005 E02003553 2394 2464 1686 39.01 25.44 40.27 32.00 31931.92 33476.91 70.4 68.4 95.4
Southampton 014 E02003562 3636 3921 2513 45.68 9.13 29.24 59.19 47112.87 51289.66 69.1 64.1 91.9
Southampton 032 E02003580 2617 2825 1786 27.21 55.48 6.65 35.69 30591.72 24488.16 68.2 63.2 124.9
Southampton 025 E02003573 3236 3470 2106 29.57 43.54 6.12 47.84 38983.67 41714.91 65.1 60.7 93.5
Southampton 003 E02003551 2256 2446 1456 33.69 38.96 15.29 42.95 27406.13 26316.61 64.5 59.5 104.1
Southampton 012 E02003560 3040 3191 1952 26.97 53.52 8.75 36.12 33850.25 34252.94 64.2 61.2 98.8
Southampton 006 E02003554 2646 2873 1684 46.49 14.55 21.05 63.00 35551.16 39712.77 63.6 58.6 89.5
Southampton 004 E02003552 2646 2809 1653 28.12 47.47 9.26 40.97 30037.47 28051.01 62.5 58.8 107.1
Southampton 028 E02003576 3434 3614 2121 38.99 22.83 18.58 56.41 39567.93 44100.48 61.8 58.7 89.7
Southampton 018 E02003566 2607 2831 1604 35.21 29.84 8.36 59.42 27084.70 36047.76 61.5 56.7 75.1
Southampton 016 E02003564 3474 3563 2124 39.38 22.54 12.09 63.39 42670.04 43718.49 61.1 59.6 97.6
Southampton 001 E02003549 2849 2832 1737 52.37 11.23 25.06 62.06 41456.28 49676.93 61.0 61.3 83.5
Southampton 002 E02003550 3216 3527 1923 43.10 21.05 11.04 66.08 36473.86 41124.17 59.8 54.5 88.7
Southampton 019 E02003567 2991 3200 1780 39.18 27.28 14.11 56.80 33242.61 43448.21 59.5 55.6 76.5
Southampton 026 E02003574 3412 3599 1972 40.77 11.78 13.66 71.72 37590.51 45562.64 57.8 54.8 82.5
Southampton 030 E02003578 2641 2830 1519 44.07 10.64 15.68 72.13 27635.37 36572.30 57.5 53.7 75.6
Southampton 024 E02003572 2484 2597 1367 45.61 8.13 15.46 75.28 30084.88 39680.38 55.0 52.6 75.8
Southampton 011 E02003559 3065 3165 1678 53.38 5.97 15.14 76.70 42375.46 55256.20 54.7 53.0 76.7
Southampton 008 E02003556 2471 2589 1321 42.57 12.51 16.15 70.42 27488.33 35612.03 53.5 51.0 77.2
ggplot2::ggplot(t, aes(x = pc_missingHH, 
                       y = pc_missingMeters,
                       colour = round(ownerOcc_pc))) +
  geom_abline(alpha = 0.2, slope=1, intercept=0) +
  geom_point() +
  scale_color_continuous(name = "% owner occupiers \n(Census 2011)", high = "red", low = "green") +
  #theme(legend.position = "bottom") +
  labs(x = "EPCs 2020 as % of Census 2011 households",
       y = "EPCs 2020 as % of electricity meters 2018",
       caption = "x = y line included for clarity")
% 'missing' rates comparison

Figure 2.1: % ‘missing’ rates comparison

outlierMSOA <- t[pc_missingHH > 100]

Figure 2.4 suggests that rates vary considerably by MSOA but are relatively consistent across the two baseline ‘truth’ estimates with the exception of E02003577 which appears to have many more EPCs than Census 2011 households. It is worth noting that this MSOA covers the city centre and dock areas which have had substantial new build since 2011 and so may have households inhabiting dwellings that did not exist at Census 2011. This is also supported by the considerably higher EPC derived energy demand data compared to BEIS’s 2018 data - although it suggests the dwellings are either very new (since 2018) or are yet to be occupied.

As we would expect those MSOAs with the lowest EPC coverage on both baseline measures tend to have higher proportions of owner occupiers.

We can use the same approach to compare estimates of total energy demand at the MSOA level. To do this we compare:

  • estimated total energy demand in MWh/year derived from the EPC estimates. This energy only relates to current primary energy (space heating, hot water and lighting) and of course also suffers from missing EPCs (see above)
  • observed electricity and gas demand collated by BEIS for their sub-national statistical series. This applies to all domestic energy demand but the most recent data is for 2018 so will suffer from the absence of dwellings that are present in the most recent EPC data (see above).

We should therefore not expect the values to match but we might reasonably expect a correlation.

ggplot2::ggplot(t, aes(x = sumEpcMWh, 
                       y = beisEnergyMWh,
                       colour = round(ownerOcc_pc))) +
  geom_abline(alpha = 0.2, slope=1, intercept=0) +
  geom_point() +
  scale_color_continuous(name = "% owner occupiers \n(Census 2011)", high = "red", low = "green") +
  #theme(legend.position = "bottom") +
  labs(x = "EPC 2020 derived total MWh/year",
       y = "BEIS 2018 derived total MWh/year",
       caption = "x = y line included for clarity")
Energy demand comparison

Figure 2.2: Energy demand comparison

outlier <- t[sumEpcMWh > 70000]

2.2 shows that both of these are true. MSOAs with a high proportion of owner occupiers (and therefore more likely to have missing EPCs) tend to have higher observed energy demand than the EOC data suggests - they are above the reference line. MSOAs with a lower proportion of owner occupiers (and therefore more likely to have more complete EPC coverage) tend to be on or below the line. As before we have the same notable outlier (E02003577) and for the same reasons… In this case this produces a much higher energy demand estimate than the BEIS 2018 data records

2.2 Check ENERGY_CONSUMPTION_CURRENT

We recode the current energy consumption into categories for comparison with other low values and the presence of wind turbines/PV. We use -ve, 0 and 1 kWh as the thresholds of interest.

ggplot2::ggplot(sotonUniqueEPCsDT, aes(x = ENERGY_CONSUMPTION_CURRENT)) +
  geom_histogram(binwidth = 5) + 
  facet_wrap(~TENURE) +
  geom_vline(xintercept = 0)
Histogram of ENERGY_CONSUMPTION_CURRENT

Figure 2.3: Histogram of ENERGY_CONSUMPTION_CURRENT

underZero <- nrow(sotonUniqueEPCsDT[ENERGY_CONSUMPTION_CURRENT < 0])

t <- with(sotonUniqueEPCsDT[ENERGY_CONSUMPTION_CURRENT < 0],
     table(BUILT_FORM,TENURE))


kableExtra::kable(t, caption = "Properties with ENERGY_CONSUMPTION_CURRENT < 0")
Table 2.5: Properties with ENERGY_CONSUMPTION_CURRENT < 0
owner-occupied rental (social) unknown
Detached 0 2 0 0
End-Terrace 2 0 2 0
Mid-Terrace 3 1 1 0
NO DATA! 0 0 0 2
Semi-Detached 6 0 0 1
# do we think this is caused by solar/wind?
sotonUniqueEPCsDT[, hasWind := ifelse(WIND_TURBINE_COUNT > 0, "Yes", "No")]
#table(sotonUniqueEPCsDT$hasWind)
sotonUniqueEPCsDT[, hasPV := ifelse(PHOTO_SUPPLY >0, "Yes", "No")]
#table(sotonUniqueEPCsDT$hasPV)
sotonUniqueEPCsDT[, consFlag := ifelse(ENERGY_CONSUMPTION_CURRENT < 0, "-ve kWh/y", NA)]
sotonUniqueEPCsDT[, consFlag := ifelse(ENERGY_CONSUMPTION_CURRENT == 0, "0 kWh/y", consFlag)]
sotonUniqueEPCsDT[, consFlag := ifelse(ENERGY_CONSUMPTION_CURRENT > 0 & 
                                     ENERGY_CONSUMPTION_CURRENT <= 1, "0-1 kWh/y", consFlag)]
sotonUniqueEPCsDT[, consFlag := ifelse(ENERGY_CONSUMPTION_CURRENT > 1, "1+ kWh/y", consFlag)]

t <- sotonUniqueEPCsDT[, .(nObs = .N), keyby = .(consFlag, hasWind, hasPV)]

kableExtra::kable(t, caption = "Properties in ENERGY_CONSUMPTION_CURRENT category by presence of microgeneration")
Table 2.5: Properties in ENERGY_CONSUMPTION_CURRENT category by presence of microgeneration
consFlag hasWind hasPV nObs
-ve kWh/y NA NA 5
-ve kWh/y No NA 15
0 kWh/y NA NA 1
0 kWh/y No No 1
1+ kWh/y NA NA 5550
1+ kWh/y No NA 33018
1+ kWh/y No No 32529
1+ kWh/y No Yes 447
1+ kWh/y Yes NA 6
1+ kWh/y Yes No 28

There are only 20 dwellings where ENERGY_CONSUMPTION_CURRENT < 0 and none of them seem to have PV or a wind turbine so we can probably ignore them.

# repeat with a density plot to allow easy overlap 
# exclude those with no data
ggplot2::ggplot(sotonUniqueEPCsDT[TENURE != "NO DATA!" &
                           TENURE != "unknown" &
                           TENURE != ""], aes(x = ENERGY_CONSUMPTION_CURRENT, 
                                              fill = TENURE, alpha = 0.2)) +
  geom_density() +
  facet_wrap(~BUILT_FORM) +
  guides(alpha = FALSE) +
  theme(legend.position = "bottom")
Comparing distributions of ENERGY_CONSUMPTION_CURRENT by tenure and built form

Figure 2.4: Comparing distributions of ENERGY_CONSUMPTION_CURRENT by tenure and built form

2.3 Check CO2_EMISSIONS_CURRENT

Next we do the same for current emissions. Repeat the coding for total floor area using 0 and 1 TCO2/y as the threshold of interest.

ggplot2::ggplot(sotonUniqueEPCsDT, aes(x = CO2_EMISSIONS_CURRENT)) +
  geom_histogram(binwidth = 1)
Histogram of CO2_EMISSIONS_CURRENT

Figure 2.5: Histogram of CO2_EMISSIONS_CURRENT

nZeroEmissions <- nrow(sotonUniqueEPCsDT[CO2_EMISSIONS_CURRENT < 0])

sotonUniqueEPCsDT[, emissionsFlag := ifelse(CO2_EMISSIONS_CURRENT < 0, "-ve CO2/y", NA)]
sotonUniqueEPCsDT[, emissionsFlag := ifelse(CO2_EMISSIONS_CURRENT == 0, "0 CO2/y", emissionsFlag)]
sotonUniqueEPCsDT[, emissionsFlag := ifelse(CO2_EMISSIONS_CURRENT > 0 & 
                                     CO2_EMISSIONS_CURRENT <= 1, "0-1 TCO2/y", emissionsFlag)]
sotonUniqueEPCsDT[, emissionsFlag := ifelse(CO2_EMISSIONS_CURRENT > 1, "1+ TCO2/y", emissionsFlag)]

t <- sotonUniqueEPCsDT[, .(nObs = .N), keyby = .(emissionsFlag, hasWind, hasPV)]

kableExtra::kable(t, caption = "Properties with CO2_EMISSIONS_CURRENT < 0 by presence of microgeneration")
Table 2.6: Properties with CO2_EMISSIONS_CURRENT < 0 by presence of microgeneration
emissionsFlag hasWind hasPV nObs
-ve CO2/y NA NA 4
-ve CO2/y No NA 16
-ve CO2/y No No 2
0 CO2/y NA NA 5
0 CO2/y No No 1
0-1 TCO2/y NA NA 3446
0-1 TCO2/y No NA 1916
0-1 TCO2/y No No 533
0-1 TCO2/y No Yes 19
0-1 TCO2/y Yes NA 1
0-1 TCO2/y Yes No 1
1+ TCO2/y NA NA 2101
1+ TCO2/y No NA 31101
1+ TCO2/y No No 31994
1+ TCO2/y No Yes 428
1+ TCO2/y Yes NA 5
1+ TCO2/y Yes No 27
kableExtra::kable(round(100*(prop.table(table(sotonUniqueEPCsDT$emissionsFlag, 
                                              sotonUniqueEPCsDT$consFlag, 
                                              useNA = "always")
                                        )
                             )
                        ,2)
                  , caption = "% properties in CO2_EMISSIONS_CURRENT categories by ENERGY_CONSUMPTION_CURRENT categories")
Table 2.6: % properties in CO2_EMISSIONS_CURRENT categories by ENERGY_CONSUMPTION_CURRENT categories
-ve kWh/y 0 kWh/y 1+ kWh/y NA
-ve CO2/y 0.03 0 0.00 0
0 CO2/y 0.00 0 0.00 0
0-1 TCO2/y 0.00 0 8.26 0
1+ TCO2/y 0.00 0 91.70 0
NA 0.00 0 0.00 0

There are 22 properties with 0 or negative emissions. It looks like they are also the properties with -ve kWh as we might expect. So we can safely ignore them.

2.4 Check ENVIRONMENT_IMPACT_CURRENT

Environmental impact should decrease as emissions increase.

ggplot2::ggplot(allEPCs_DT, aes(x = ENVIRONMENT_IMPACT_CURRENT)) +
  geom_histogram()
## `stat_bin()` using `bins = 30`. Pick better value with `binwidth`.
Histogram of ENVIRONMENT_IMPACT_CURRENT

Figure 2.6: Histogram of ENVIRONMENT_IMPACT_CURRENT

So what is the relationship between ENVIRONMENT_IMPACT_CURRENT and CO2_EMISSIONS_CURRENT? It is not linear… (Figure 2.7) and there are some interesting outliers.

ggplot2::ggplot(allEPCs_DT, aes(x = CO2_EMISSIONS_CURRENT, 
                           y = ENVIRONMENT_IMPACT_CURRENT,
                           colour = TENURE)) +
  geom_point() +
  facet_wrap(TENURE~.) +
  theme(legend.position = "bottom")
PLot of ENVIRONMENT_IMPACT_CURRENT vs CO2_EMISSIONS_CURRENT

Figure 2.7: PLot of ENVIRONMENT_IMPACT_CURRENT vs CO2_EMISSIONS_CURRENT

2.5 Check TOTAL_FLOOR_AREA

Repeat the coding for total floor area using 5 m2 as the threshold of interest.

ggplot2::ggplot(sotonUniqueEPCsDT, aes(x = TOTAL_FLOOR_AREA)) +
  geom_histogram(binwidth = 1)
Histogram of TOTAL_FLOOR_AREA

Figure 2.8: Histogram of TOTAL_FLOOR_AREA

nZeroFloorArea <- nrow(sotonUniqueEPCsDT[TOTAL_FLOOR_AREA < 0])

sotonUniqueEPCsDT[, floorFlag := ifelse(TOTAL_FLOOR_AREA == 0, "0 m2", NA)]
sotonUniqueEPCsDT[, floorFlag := ifelse(TOTAL_FLOOR_AREA > 0 & 
                                     TOTAL_FLOOR_AREA <= 10, "0-5 m2", floorFlag)]
sotonUniqueEPCsDT[, floorFlag := ifelse(TOTAL_FLOOR_AREA > 10, "5+ m2", floorFlag)]

t <- with(sotonUniqueEPCsDT, table(floorFlag, consFlag))

kableExtra::kable(round(100*prop.table(t),2), caption = "% properties with TOTAL_FLOOR_AREA category by ENERGY_CONSUMPTION_CURRENT category")
Table 2.7: % properties with TOTAL_FLOOR_AREA category by ENERGY_CONSUMPTION_CURRENT category
-ve kWh/y 0 kWh/y 1+ kWh/y
0 m2 0.00 0 0.10
0-5 m2 0.00 0 0.02
5+ m2 0.03 0 99.85
kableExtra::kable(head(sotonUniqueEPCsDT[, .(BUILDING_REFERENCE_NUMBER, PROPERTY_TYPE, TOTAL_FLOOR_AREA, 
                                    ENERGY_CONSUMPTION_CURRENT)][order(-TOTAL_FLOOR_AREA)], 10), 
                  caption = "Top 10 by floor area (largest)")
Table 2.7: Top 10 by floor area (largest)
BUILDING_REFERENCE_NUMBER PROPERTY_TYPE TOTAL_FLOOR_AREA ENERGY_CONSUMPTION_CURRENT
4.697565e-314 House 1353.680 140
1.894551e-314 House 1123.000 120
4.846111e-314 House 973.210 522
2.559778e-314 House 861.360 279
8.172097e-315 House 855.000 170
4.440838e-315 House 846.421 161
1.933817e-314 House 833.000 206
4.076249e-314 House 800.000 185
1.280057e-314 House 714.000 224
2.444460e-314 Flat 694.000 88
kableExtra::kable(head(sotonUniqueEPCsDT[, .(BUILDING_REFERENCE_NUMBER, PROPERTY_TYPE, TOTAL_FLOOR_AREA,
                                    ENERGY_CONSUMPTION_CURRENT)][order(TOTAL_FLOOR_AREA)], 10), 
                  caption = "Bottom 10 by floor area (smallest)")
Table 2.7: Bottom 10 by floor area (smallest)
BUILDING_REFERENCE_NUMBER PROPERTY_TYPE TOTAL_FLOOR_AREA ENERGY_CONSUMPTION_CURRENT
9.111592e-316 Flat 0 104
3.102124e-315 Flat 0 58
3.294384e-315 Flat 0 110
3.695003e-315 Flat 0 70
4.369619e-315 Flat 0 119
4.371685e-315 Flat 0 71
7.302298e-315 Flat 0 115
9.515727e-315 Flat 0 144
9.562249e-315 Flat 0 103
1.059979e-314 Flat 0 117
kableExtra::kable(round(100*prop.table(t),2), caption = "% properties with TOTAL_FLOOR_AREA category by ENERGY_CONSUMPTION_CURRENT category")
Table 2.7: % properties with TOTAL_FLOOR_AREA category by ENERGY_CONSUMPTION_CURRENT category
-ve kWh/y 0 kWh/y 1+ kWh/y
0 m2 0.00 0 0.10
0-5 m2 0.00 0 0.02
5+ m2 0.03 0 99.85

2.6 shows that the properties with floor area of < 10m2 are not necessarily the ones with 0 or negative kWh values. Nevertheless they represent a small proportion of all properties.

The scale of the x axis also suggests a few very large properties.

2.6 Data summary

We have identified some issues with a small number of the properties in the EPC dataset. These are not unexpected given that much of the estimates rely on partial or presumed data. Data entry errors are also quite likely. As a result we exclude:

  • any property where ENERGY_CONSUMPTION_CURRENT <= 0
  • any property where TOTAL_FLOOR_AREA <= 5
  • any property where CO2_EMISSIONS_CURRENT <= 0
finalDT <- sotonUniqueEPCsDT[ENERGY_CONSUMPTION_CURRENT > 0 &
                      TOTAL_FLOOR_AREA > 5 &
                      CO2_EMISSIONS_CURRENT > 0]

skimr::skim(finalDT)
## Warning: Couldn't find skimmers for class: integer64; No user-defined `sfl` provided. Falling back
## to `character`.
Table 2.8: Data summary
Name finalDT
Number of rows 71501
Number of columns 23
_______________________
Column type frequency:
character 12
Date 1
numeric 10
________________________
Group variables None

Variable type: character

skim_variable n_missing complete_rate min max empty n_unique whitespace
BUILDING_REFERENCE_NUMBER 0 1.00 17 21 0 71501 0
LMK_KEY 0 1.00 29 34 0 71501 0
PROPERTY_TYPE 0 1.00 4 10 0 5 0
BUILT_FORM 0 1.00 8 20 0 7 0
TENURE 0 1.00 0 16 1906 6 0
POSTCODE 0 1.00 8 8 0 5105 0
LOCAL_AUTHORITY_LABEL 0 1.00 11 11 0 1 0
hasWind 5547 0.92 2 3 0 2 0
hasPV 38499 0.46 2 3 0 2 0
consFlag 0 1.00 8 8 0 1 0
emissionsFlag 0 1.00 9 10 0 2 0
floorFlag 0 1.00 5 6 0 2 0

Variable type: Date

skim_variable n_missing complete_rate min max median n_unique
LODGEMENT_DATE 0 1 2008-10-01 2020-06-30 2014-10-22 4132

Variable type: numeric

skim_variable n_missing complete_rate mean sd p0 p25 p50 p75 p100 hist
ENVIRONMENT_IMPACT_CURRENT 0 1.00 62.52 15.70 1.00 52.0 63.0 73 100.00 ▁▂▆▇▂
ENERGY_CONSUMPTION_CURRENT 0 1.00 263.17 140.44 4.00 174.0 233.0 327 1597.00 ▇▂▁▁▁
CO2_EMISSIONS_CURRENT 0 1.00 3.16 1.94 0.10 1.8 2.8 4 77.00 ▇▁▁▁▁
PHOTO_SUPPLY 38499 0.46 0.59 5.12 0.00 0.0 0.0 0 100.00 ▇▁▁▁▁
WIND_TURBINE_COUNT 5547 0.92 0.00 0.02 -1.00 0.0 0.0 0 1.00 ▁▁▇▁▁
TOTAL_FLOOR_AREA 0 1.00 73.05 34.87 5.85 49.0 69.0 87 1353.68 ▇▁▁▁▁
epcIsSocialRent 0 1.00 0.21 0.40 0.00 0.0 0.0 0 1.00 ▇▁▁▁▂
epcIsPrivateRent 0 1.00 0.27 0.44 0.00 0.0 0.0 1 1.00 ▇▁▁▁▃
epcIsOwnerOcc 0 1.00 0.41 0.49 0.00 0.0 0.0 1 1.00 ▇▁▁▁▆
epcIsUnknownTenure 0 1.00 0.04 0.19 0.00 0.0 0.0 0 1.00 ▇▁▁▁▁

This leaves us with a total of 71,501 properties. ` # Current estimated annual CO2 emmisions

We can now use the cleaned data to estimated the annual CO2 emissions at:

  • MSOA level for Southampton using
    • BEIS observed data
    • aggregated EPC data
  • Dwelling level for Southampton using
    • aggregated EPC data

Obviously the EPC-derived totals will not be the total CO2 emissions for all Southampton properties since we know not all dwellings are represented in the EPC data (see above).

2.7 MSOA estimates

Method:

elecCF <- 200 # CO2e/kWh https://www.icax.co.uk/Grid_Carbon_Factors.html
gasCF <- 215 # https://www.icax.co.uk/Carbon_Emissions_Calculator.html

BEIS: apply 2019 mean grid carbon intensity for: * electricity: 200 g * gas: 215 g CO2e/kWh EPC: use estimated CO2 values - note based on ‘old’ electricity grid carbon intensity values ()

sotonMSOA_DT[, sumBEIS_tCO2 := (beisElecMWh/1000)*elecCF + (beisGasMWh/1000)*gasCF]
ggplot2::ggplot(sotonMSOA_DT, aes(x = sumBEIS_tCO2, 
                       y = sumEPC_tCO2,
                       colour = round(ownerOcc_pc))) +
  geom_abline(alpha = 0.2, slope=1, intercept=0) +
  geom_point() +
  scale_color_continuous(name = "% owner occupiers \n(Census 2011)", high = "red", low = "green") +
  #theme(legend.position = "bottom") +
  labs(x = "EPC 2020 derived total T CO2/year",
       y = "BEIS 2018 derived total T CO2/year",
       caption = "x = y line included for clarity")
Energy demand comparison

Figure 2.9: Energy demand comparison

#outlier <- t[sumEpcMWh > 70000]

2.2 shows that

3 Carbon Tax Scenarios

3.1 No change to carbon intensity

Applying these rates enables us to calculate the Southampton and MSOA level Carbon Tax liability of households via the EPC and BEIS observed energy consumption methods.

sotonMSOA_DT[, ct_BEIS := sumBEIS_tCO2 * 16]
sotonMSOA_DT[, ct_EPCs := sumEPC_tCO2 * 16]

t <- sotonMSOA_DT[, .(CarbonTaxBEIS_GBP = prettyNum(sum(ct_BEIS), big.mark = ","),
                      CarbonTaxEPCs_GBP = prettyNum(sum(ct_EPCs), big.mark = ",")),
                  keyby = .(LAName)]

kableExtra::kable(t, caption = "Estimated Carbon tax liability for Southampton households/properties under Scenario 1") %>%
  kable_styling()
Table 3.1: Estimated Carbon tax liability for Southampton households/properties under Scenario 1
LAName CarbonTaxBEIS_GBP CarbonTaxEPCs_GBP
Southampton 4,300,808 3,609,088

As we would expect the values are relatively close due to the similar total emissions values estimated above.

If we look at the values by MSOA (3.1), we find that values differ quite substantially between the methods depending on the levels of EPC records (or missing households - see above) that we are likely to have.

ggplot2::ggplot(sotonMSOA_DT, aes(x = ct_BEIS/1000, 
                       y = ct_EPCs/1000,
                       colour = round(ownerOcc_pc))) +
  geom_abline(alpha = 0.2, slope=1, intercept=0) +
  geom_point() +
  scale_color_continuous(name = "% owner occupiers \n(Census 2011)", high = "red", low = "green") +
  #theme(legend.position = "bottom") +
  labs(x = "EPC 2020 derived total Carbon Tax £k/year",
       y = "BEIS 2018 derived total Carbon Tax £k/year",
       caption = "x = y line included for clarity")
Energy demand comparison

Figure 3.1: Energy demand comparison

#outlier <- t[sumEpcMWh > 70000]

Perhaps of more interest however is the relationship between estimated Carbon Tax £ and levels of deprivation. Figure 3.2 shows the estimated total Carbon Tax (in £k per year) per MSOA against the proportion of households in the MSOA who do not suffer from any dimension of deprivation as defined by the English Indices of Multiple Deprivation. As we can see the higher the proportion of households with no deprivation, the higher the total MSOA Carbon Tax. This suggests that a Carbon Tax will be regressive - those who pay the most are likely to be those who use more energy and thus are likely to be those who can afford to do so.

But we need to be very careful. Some deprived households might well spend a high proportion of their income on energy in order to heat very energy efficient homes. For them, a Carbon Tax would be similar to VAT - an additional burden that might be relatively small in £ terms (compared to a well-off high energy-using household) but high in terms of the % of their income (or expenditure). This is a well known issue highlighted by recent ONS data on family energy expenditures.

t1 <- sotonMSOA_DT[, .(MSOACode, ctSum = ct_EPCs, dep0_pc)]
t1[, source := "BEIS 2018"]
t2 <- sotonMSOA_DT[, .(MSOACode, ctSum = ct_BEIS, dep0_pc)]
t2[, source := "EPC 2020"]

plotDT <- rbind(t1,t2)

ggplot2::ggplot(plotDT, aes(x = dep0_pc, y = ctSum, colour = source)) +
  geom_point() +
  geom_smooth() +
  #theme(legend.position = "bottom") +
  labs(x = "% with no deprivation dimensions \n(Census 2011)",
       y = "Carbon Tax £k/year",
       caption = "x = y line included for clarity")
## `geom_smooth()` using method = 'loess' and formula 'y ~ x'
Energy demand comparison

Figure 3.2: Energy demand comparison

#outlier <- t[sumEpcMWh > 70000]

3.2 National Grid’s Future Energy Scenarios:

  • 2030 emissions level for electricity of 0.102 kgCO2/kWh
  • gas unchanged

4 R packages used

  • rmarkdown (Allaire et al. 2018)
  • bookdown (Xie 2016a)
  • knitr (Xie 2016b)
  • data.table (Dowle et al. 2015)
  • ggplot2 (Wickham 2009)
  • kableExtra (Zhu 2018)
  • readxl (Wickham and Bryan 2017)

References

Allaire, JJ, Yihui Xie, Jonathan McPherson, Javier Luraschi, Kevin Ushey, Aron Atkins, Hadley Wickham, Joe Cheng, and Winston Chang. 2018. Rmarkdown: Dynamic Documents for R. https://CRAN.R-project.org/package=rmarkdown.

Dowle, M, A Srinivasan, T Short, S Lianoglou with contributions from R Saporta, and E Antonyan. 2015. Data.table: Extension of Data.frame. https://CRAN.R-project.org/package=data.table.

Wickham, Hadley. 2009. Ggplot2: Elegant Graphics for Data Analysis. Springer-Verlag New York. http://ggplot2.org.

Wickham, Hadley, and Jennifer Bryan. 2017. Readxl: Read Excel Files. https://CRAN.R-project.org/package=readxl.

Xie, Yihui. 2016a. Bookdown: Authoring Books and Technical Documents with R Markdown. Boca Raton, Florida: Chapman; Hall/CRC. https://github.com/rstudio/bookdown.

———. 2016b. Knitr: A General-Purpose Package for Dynamic Report Generation in R. https://CRAN.R-project.org/package=knitr.

Zhu, Hao. 2018. KableExtra: Construct Complex Table with ’Kable’ and Pipe Syntax. https://CRAN.R-project.org/package=kableExtra.