UMEP Manual/ Tutorials/GQF

Aim

This tutorial demonstrates how the GQF software is used to simulate anthropogenic heat fluxes for London, UK, in the year 2015, using a mixture of administrative and meteorological data.

Initial Practical steps

UMEP is a python plugin used in conjunction with QGIS. To install the software and the UMEP plugin see the getting started section in the UMEP manual.

As UMEP is under constant development, some documentation may be missing and/or there may be instability. Please report any issues or suggestions to our repository.

Data for this exercise

In order to proceed, you will need the zip file named GQF_Inputs_1.zip from the UMEP tutorials data repository.

You may also wish to consult the GQF user guide

The GQF_Inputs_1.zip file contains several datasets to cover the comprehensive requirements of GQF:

Filename Description Notes
500m_Residential_from_100m.shp Residential population Attribute: "Pop", Feature ID: "ID"
500m_Workday_from_100m.shp Workday population Attribute: "Pop"
MSOA_elec_gas_2014.shp Industrial gas use (annual) Attribute:"GasInd"
LA_energy_2014.shp Industrial electricity use (annual) Attribute:"ElInd_kWh"
LSOA_elec_gas_2014.shp Domestic gas and electricity use (annual) Attributes:"GasDom", "TelDom"
2015GasElecDD.csv Day-to-day variations in gas and electricity use Year 2015
BuildingLoadings_DomUnre.csv Weekend and weekday diurnal profiles of domestic energy use 6 seasonal variants
BuildingLoadings_Industrial.csv Weekend and weekday diurnal profiles of industrial energy use 6 seasonal variants
BuildingLoadings_EC7.csv Weekend and weekday diurnal profiles of domestic economy 7 energy use File required for model execution but data not actually used
fuelConsumption.csv Fuel efficiency (g/km) of different vehicle classes
Transport.csv Weekend and weekday diurnal profiles for each vehicle class
Metabolism.csv Weekend and weekday diurnal profiles of metabolic activity
Parameters.nml Configuration file containing model run parameters
DataSources.nml Configuration file specifying different input data sources for model

GQF Tutorial 1: Comprehensive QF modelling for Greater London

Preparing data

Manage input data files

• Extract the contents of GQF_Inputs_1.zip into a folder on your local machine and note the path to each file (e.g. C:\GQFData\BuildingLoadings_Industrial.csv)

GQF uses multiple shapefiles (ending .shp) to build up a picture of energy use, population and road transport across the city. Five pieces of information are needed for each of these:

1. Filename: The full path to the .shp file (e.g. c:\path\to\file.shp)
2. Start date: The modelled date from which this data should be used
3. EPSG code: A numeric code that determines which co-ordinate reference system (CRS) to use for the shapefile
4. Attribute to use. A shapefile attaches one or more attributes (e.g. population or energy consumption) to each spatial unit. The name of the relevant attribute must be specified here.
5. Feature IDs: The name of an attribute that contains a unique identifier for each spatial unit

Click here for a guide explaining how to identify the feature ID, attribute to use and EPSG code of a shapefile using QGIS.

A shapefile also defines the so-called output areas, which are the spatial units (sometimes pixels) of model output (one QF estimate per area). These are needed because the spatial units of the various input files may not all match up. The output areas can either be one of the input files, or a totally different set of areas. In this tutorial, one of the population datasets is used to keep things simple.

Set up the DataSources.nml file

The data sources file needs to be updated so that it can find the various data files, and understands what to do with them. A full description of the Data sources file contents is available here, but this section shows how to build up the entries.

There are several sections in the data sources file. Each is bounded by &section_name and ends with "/" and deals with a different part of the input data.

1. Open DataSources.nml using a text editor (we recommend Notepad++).
2. The following steps show how to update the entries according to the information gathered above.

1. The "shapefile" entry is the path to the file
2. The epsgCode and featureIds entries are found by inspecting each file using QGIS. Note that each file has different values for these
3. The attribToUse entry for each file is covered in the table above
4. An arbitrary start date of 2011-01-01 (1st january) can be used for the data shown.

For brevity, just the first two sections of the DataSources.nml file are shown here: Using the workday population spatial units as model output areas. This section does not need to use an attribute or know about a start date:

&outputAreas
shapefile = 'C:\path\to\data\500m_Workday_from_100m.shp'
epsgCode = 32631
featureIds = 'ID'
/


Specifying the residential population data.

! ### Population data
&residentialPop
shapefiles = 'C:\path\to\data\500m_Residential_from_100m.shp'
startDates = '2011-01-01'
epsgCodes = 32631
attribToUse = 'Pop'
featureIds = 'ID'
/


The same pattern is used for the other spatial input datasets:

• workplacePop: Workplace/workday population dataset
• annualIndGas: Industrial gas use
• annualIndElec: Industrial electricity use
• annualDomGas: Domestic gas use
• annualDomElec: Domestic electricity use (same file as domestic gas, but different attribute)

For the annualEco7 section, we shall assume zero consumption. This doesn't need a shapefile - a single number indicating the whole-city consumption should be used instead, along with dummy EPSG code, attribToUse and featureIds:

&annualEco7
! Spatial variations of economy 7 electricity use
shapefiles = 0.0
startDates = '2014-01-01'
epsgCodes = 1
attribToUse = 'IndGas' !A dummy name
featureIds =
/


Day-to-day energy demand changes

GQF uses annual total energy consumption shapefiles, and needs to know how to vary energy consumption on different dates (e.g. winter is likely to have more fuel use than summer). This is captured using real data from the energy grid. The 2015GasElecDD.csv file contains each day's total gas and electricity consumption. GQF then scales the annual consumption based on this each day.

&dailyEnergyUse
! Daily variations in total power use
profileFiles = 'C:\Path\To\2015GasElecDD.csv'
/


Only the year(s) represented by the data should be modelled, but if only past years are available GQF will recycle it for later years, offering the closest sensible match to time of week and time of year.

Metabolism file

The metabolism file controls:

• How much energy each the average person emits at each time of day
• The fraction of an area's workday population actually at work (and by extension the fraction of the residential population at home)

The 'metabolism.csv' file contains a weekday, saturday and sunday variant of this information, and copies for each daylight savings regime in the UK to account for changes in the summer.

! Temporal metabolism data
&diurnalMetabolism
profileFiles = 'N:\QF_London\GreaterQF_input\London\Profiles\\Metabolism.csv'
/


Building diurnal profiles

As shown above, the different kinds of building energy consumption are separated in GQF. Their diurnal profiles are also different so that the different behaviours of households and businesses are represented accurately. This means that each of the building energy inputs also requires a diurnal profile data file:

&diurnalDomElec
! Diurnal variations in total domestic electricity use (metadata provided in file; files can contain multiple seasons)
profileFiles =
/
&diurnalDomGas
! Diurnal variations in total domestic gas use (metadata provided in file; files can contain multiple seasons)
/
&diurnalIndElec
! Diurnal variations in total industrial electricity use (metadata provided in file; files can contain multiple seasons)
/
&diurnalIndGas
! Diurnal variations in total industrial gas use (metadata provided in file; files can contain multiple seasons)
/
&diurnalEco7
! Diurnal variations in total economy 7 electricity use (metadata provided in file; files can contain multiple seasons)
/


The transport input data files are very detailed and therefore needs a lot of descriptive information in the &transportData section of DataSouces.nml

Shapefile

To save time, the DataSources file is mostly completed in advance with entries that reflect the transport shapefile, but some of the key entries still need completing as part of the tutorial:

• The location, EPSG code, feature ID and start date of the road transport shapefile
• Information about what is available in the shapefile

It should be possible to complete and/or verify the first four entries using the table and information above.

The next three entries should be all be set to 1 to signify that they are provided by the shapefile

&transportData
! Vector data containing all road segments for study area
startDates = '2008-01-01'
epsgCodes = 27700
featureIds = 'OBJECTID'

! What data is available for each road segment in this shapefile? 1 = Yes; 0 = No
speed_available = 1                 ! Speed data. If not available then default values from parameters file are used
total_AADT_available = 1            ! Total annual average daily total (AADT: total vehicles passing over each segment each day)


The rest of the section tells GQF which attributes to use for various aspects of the traffic data, and what different kinds of roads are called:

   ! Road classification information. This is used with assumed values for AADT
class_field = 'DESC_TERM'           ! The shapefile attribute that contains road classification
! Strings that identify each class of road
motorway_class = 'Motorway'
! All other road types will be considered as "other"

! Average speed for each road segment
speed_field = 'Speed_kph'           ! Field name
speed_multiplier = 1.0              ! Factor that converts data to km/h (1.0 if data is already in km/h)

! Annual average daily total (mean number of vehicles per day) passing over each road segment in the shapefile
! Specify attribute names if data is present in the shapefile.

! AADT for cars of different fuels (leave as  if not available)
! Secondary option: Use total AADT for cars and break down using assumed fuel fractions from model parameters file
AADT_total_car =                ! Total AADT for all cars (required if the other car fields are ; ignored if they are specified)

! AADT for LGVs of different fuels leave as  if not available)
! Secondary option: Use total LGV AADT and assumed fuel fractions from parameters file
AADT_total_LGV =                ! Total AADT for all LGVs (required if the other LGV fields are ; ignored if they are specified)

! AADT for other vehicles. These are broken down into diesel/petrol based on fuel fractions (see model parameters file)
! Specify shapefile attribute name or leave as  if not available
/


Vehicle fuel efficiency data

The fuelConsumption.csv file contains a list of vehicle fuel efficiency by fuel, vehicle type and era. This is used to calculate each road link's fuel consumption:

&fuelConsumption
! File containing fuel consumption performance data for each vehicle type as standards change over the years
profileFiles = 'C:\Path\To\fuelConsumption.csv'
/


Diurnal profiles by vehicle type

Each vehicle type has a different activity profile. For example, freight and taxi vehicle may operate later at night than passenger cars. The Transport.csv file contains a profile for each of these:

&diurnalTraffic
! Diurnal cycles of transport flow for different vehicle types
profileFiles = 'C:\Path\To\Transport.csv'
/


Each profile is a week long, and these profiles control changes to the total volume of traffic each day.

Run GQF

Under UMEP > Processor > Urban Energy Balance, choose GQf (GreateRQF)

This loads the model interface dialog box:

Choose configuration files and output folder

Working from the top of the dialog box to the bottom...

1. Click the … buttons in the "Configuration and raw input data" panel to browse to the parameters.nml and DataSources.nml files. A pop-up error message will warn of any problems inside the files.
2. Output path: A folder in which the model outputs will be stored. It is strongly recommended that a new folder is used each time.
3. Click Prepare input data using Data Sources button. This may be a time-consuming step: It matches the various inputs to each output area. Where output areas and input shapes are not identical, it also splits population or energy use across output areas based on their overlapping fractions.
4. Once this step is complete, the “available at:” box will become populated. This folder contains the disaggregated data needed to run the model.

Tip: Save time in future: If the exact same input data files are used in a later study, then the “prepare” step can be skipped: click the “…” button and navigate to a folder that contains the relevant disaggregated data. It will then be copied to the new output folder and used as normal.

Run the model for 1 week

Choose a start date of 11 May 2015, using the start and end date boxes, then select "Run".

Visualise results

Once the model run this is finished, press “visualise outputs” to view some of the model results to open the visualisation tool.

Create emissions maps at noon

Use the visualisation tool to create a map of all the QF components at noon (11:00-12:00 UTC) on May 11 by selecting that time and pressing “Add to canvas”. This may take a moment to process. Close the visualisation took and return to the main canvas to inspect the four new layers that have appeared.

Each layer corresponds to a different QF component:

• Metab: Metabolism
• TransTot: Total from all road transport sources
• AllTot: Total QF from all emissions
• BldTot: Total building emissions

De-selecting a layer in the Layers panel removes it from view.

Leaving just AllTot(total QF) visible, there isn’t much structure in the colours.

Total QF at Noon on May 11

Add some contrast to it by choosing a different colour scale:

Right-click the Qf layer, go to Properties > Style, change the colour ramp to “Reds” and choose Mode: Natural Breaks (Jenks). This shows much more structure, although the grid borders are distracting. These can be removed by double-clicking the colour levels and choosing a border colour the same as the fill colour.

Total QF at Noon on May 11

The roads have a very different spatial pattern to buildings, so these can also be visualised by selecting the TransTot layer and re-colouring accordingly:

GQF Transport QF at 1200 UTC

Plot a time series of QF in the centre of the city

A time series can be shown for any of the output areas. To identify one of interest, zoom into the city centre, choose the selection tool and click an output area of interest.

This turns yellow. Right-click it and select the option that comes up.

Information about the output area then appears on the left, with the ID shown. Make a note of this.

Return to the visualisation tool, choose output area 5448 and click “show plot”. Time series of each QF component then appear for the week. Note the lower traffic activity and different behaviours on Saturday and Sunday, when people are expected to not be at work.

Time series of QF emissions

Tutorials 2: Refining GQF results

There are several extra options in GQF. The following mini-tutorials show how they are used:

Tutorial 2a: Add a public holiday

The parameters.nml file contains three entries related to public holidays, which are treated as the second day of the weekend by GQF:

• Use_UK_holidays: Religious and recurrent public holidays from the UK are calculated automatically
• Use_custom_holidays: Set to 1 in order to have GQF read in a list of user-provided holidays
• custom_holidays: A comma-separated list of dates that should be treated as holidays in format YYYY-mm-dd (e.g. "2015-05-07", "2015-07-30")

In this example, a fictional public holiday of 2015-05-13 is entered into the parameters.nml file. The model is then run as in Tutorial 1, and the resulting time series in output area 5448 is shown below:

Time series with extra public holiday on May 13

Compared against the results from Tutorial 1, the curve on May 13 in each sub-plot now resembles May 17 (a Sunday) rather than the weekdays around it.

Tutorial 2b: Remove the sensible heat component

Anthropogenic heat is made up of three parts:

• Sensible: Transported by convection (usually the largest share)
• Latent: Transported by the vaporisation of water
• Wastewater: Heat in water ejected by buildings

GQF includes all of these in the calculated fluxes by default, but one or more of them can be removed at model run-time using the checkboxes:

In this example, the week of 11 to 18 May 2015 is again modelled but the "Sensible" and "Wastewater" checkboxes are un-ticked. This means the modelled QF will contain only latent heat. The resulting time series in area 5448 is shown below:

Time series with only latent and wastewater contributions included, and extra public holiday on May 13

The emissions are far lower than those in Tutorial 2a, showing how latent heat is a relatively small contribution. Consuming electricity emits no latent heat, unlike gas, while metabolism now represents a larger fraction of the total.