HOMER Grid 1.1
HOMER has partnered with Genability, a company that specializes in maintaining a database of tariffs. To choose a tariff follow these 6 steps:
Step 1: Click on Utility and select the "Choose Tariff" tab.
Step 2: Select the Country from the dropdown;HOMER Grid supports tariffs in United States, Mexico, Canada and Australia.
Step 3: Enter the zip code / postal code of your project. Hit the "Get Tariffs" button
You will see a table such as shown below. This table contains a list of tariffs that apply to that zip code/postal code.
The meaning of the columns in the tariff table are explained below:
|
Variable |
Description |
|
Name |
Name of the tariff. This can be found on the monthly electricity bill |
|
Code |
This a popular short code assigned to a tariff for purpose of easy reference. For example "E-19" or "A-2" |
|
Popularity |
The number of customers that are on this tariff. It is to be noted that sometimes the value for Popularity might be 0, this does not mean that there are no customers on this tariff. It only means that Genability could not find data on the popularity of this particular tariff. |
|
Utility |
Name of the utility company that has created that tariff |
|
Minimum Demand (kW) |
This is a minimum demand requirement that a customer has to satisfy to be eligible to use this tariff. If this field is empty then it means that there is no such eligibility requirement. |
|
Maximum Demand (kW) |
This is a maximum demand requirement that a customer has to satisfy to be eligible to use this tariff. If this field is empty then it means that there is no such eligibility requirement. |
|
Minimum Consumption(kWh/month) |
This is a minimum monthly consumption requirement that a customer has to satisfy to be eligible to use this tariff. If this field is empty then it means that there is no such eligibility requirement. |
|
Maximum Consumption (kWh/month) |
This is a maximum monthly consumption requirement that a customer has to satisfy to be eligible to use this tariff. If this field is empty then it means that there is no such eligibility requirement. |
|
Supported |
A blue tick in this variable means that HOMER Grid supports this tariff, and it can be used to create a model. If there is no blue tick in this variable, and you need to use that tariff please get in touch with HOMER support at support@homerenergy.com |
Step 3: Double click on the tariff you need. A information page about the tariff will be displayed.
Example shown below for the "A-1" tariff by Pacific Gas & Electric Co
Step 4: The above tariff information page might need additional inputs from the user. For more information on the tariff, click on the context sensitive help (shown below) for a pdf document from the Utility on the detailed break down of costs.
Step 5: Use the "Compute Bill" to check if HOMER Grid can match the costs to an actual electricity bill. This feature can be used only if the user has entered an electrical load in the model.
To view the actual costs, choose the "Table" option as shown below. This table should give the monthly break down of costs. These costs can then be used to compare with an actual electricity bill.
You can also view the consumption and demand rates graphs in the properties section:
Step 6: Enter non-tariff related inputs:
- Grid sale limit (kW)
A sensitivity variable that can be used to limit the amount of grid sale that is allowed (kW)
- Emissions
The Emissions tab allows you to specify emissions factors for several pollutants.
|
Variable |
Description |
|
Carbon Dioxide |
The amount of carbon dioxide released per kWh of grid power consumed by the system, in grams/kWh |
|
Carbon Monoxide |
The amount of carbon monoxide released per kWh of grid power consumed by the system, in grams/kWh |
|
Unburned Hydrocarbons |
The amount of unburned hydrocarbons released per kWh of grid power consumed by the system, in grams/kWh |
|
Particulate Matter |
The amount of particulate matter released per kWh of grid power consumed by the system, in grams/kWh |
|
Sulfur Dioxide |
The amount of sulfur dioxide released per kWh of grid power consumed by the system, in grams/kWh |
|
Nitrogen Oxides |
The amount of nitrogen oxides released per kWh of grid power consumed by the system, in grams/kWh |
HOMER uses these emissions factors to calculate:
•The emissions of each pollutant resulting from grid power purchases.
•The avoided emissions of each pollutant resulting from grid power sales.
The values of these coefficients depend on the generation mix of the electricity in your area. In an area where the majority of the electricity is produced from coal, these values are relatively high because burning coal results in large emissions of pollutants. Natural gas generation results in somewhat lower emissions, and nuclear and hydro generation result in virtually no emissions of these pollutants.
See the table of US grid emissions factors section in the help for more information. For additional resources, see the Finding data to run HOMER section.
See also
How HOMER Calculates Emissions
