PV Results

Utilicé el SAM para simular un Photovoltaic (detailed) Residential (Distributed) System. El sitema tiene 6 paneles de 260 Wp en paralelo. EL hogar tiene un consumo mensual de 210 kWh. La energia de la red se compra a "Rates for energy Charges; buy ($3.70/kWh). Los resultados de SAM fueron: Annual Energy (year 1) 2299 kWh; Electricity bill without system (Year 1) $44.00, Electricity bill with system (Year 1) $ 37.00, Net savings with system $ 7.00. Me parece que el "Electricity bill without system" y el "Electricity bill with system" son muy bajos. Que hice mal? Adjunto el Archivo para que lo revisen.

Cordiales saludos

Hello,

The problem with the "electricity bill without system" result is on the Electricity Rates page, where you set "Max. Usage" for the energy charge Tier 1 to 1. That limits the energy charge to 1 kWh per month. You should change that number to a very large value, for example, the default value is 1e+38.

Best regards,
Paul.

Many thanks for your reply. I already made the change of "Max Usage" 1 to 1E+38 and the results seem to me are great. It is my first time using SAM. In Honduras, my country of origin, for the moment there is no economic incentives, there is no purchase of the extra generated energy by the PV system, or payment for the energy consumed from the PV system. The only incentive is the energy that is no to consume from the grid with the PV system running, but there is also no taxs specific to have a PV system or taxs by the energy generated. Could you check the example to see if I wrote well these parameters?

An issue that is vital in these calculations and serves much to sell PV systems is the reduction of the grid energy consumption invoice when the PV system it is generating. And this is in direct relationship with the curve of daily consumption of energy versus the values of incident solar radiation. Can we see in SAM yhe daily energy consumption curve or data, that you used? Can we see the relationship between the curve or data of daily energy consumption versus the incident solar radiation?.How does SAM calculate the electricity invoice with the system PV working?

Best Regards.

Rei

Dear Rei,

On the Electricity Rates input page, the "Monthly total excess rolled over to next month bill in kWh" means that the electricity customer receives a credit on each month's electricity bill (invoice) for excess generation in the previous month. This arrangement is often called net metering. If net metering is not available in your area, you should choose the "Cumulative hourly (subhourly) excess credited to current month bill in $ at sell rate," and then set the sell rate in the energy charge table to zero.

You can see daily profile data on the Results page by clicking the "Profiles" tab. You can use those graphs to plot load data and subarray POA solar data.

Best regards,
Paul.

Many thanks Paul. As there is no net metering, or feed in tariff in my country I used the "Cumulative hourly (subhourly) excess credited to current month bill in $ at sell rate" option and then I set the sell rate in the energy charge table to zero. The results are really not flattering for this type of system,The payback period is 18.6 years.

Talking about other topics. Have you planned to do a SAM version and trainings in Spanish?