On the first day of the year, the battery (yes, only 1) is discharged to a SOC of 30%. The battery is not recharged nor is it used again. I am wondering what HOMER is thinking when it uses a battery only once. this case is only $0.001 more expensive than the case without the battery, so I would not use a battery. But, why use the battery only o

I was just wondering what was the control strategy used by HOMER when 2 different generators are present in the same system. What is the generator used in priority? Each hour, HOMER looks at the available dispatchable generators and chooses to operate the one that can produce the required amount of power and operating reserve most cheaply. The

In generator dispatch strategy, I am wondereing have i made a correct decision chosing cycle following and a set-point of 80%? (Is it possible to tick both load folowing a nd cycle charging at the same time. Is it possible or advisable?) It's both possible and advisable to check both cycle charging and load following. It just means HOMER will

When I use the cycle charging dispatch strategy in my simulations, what happens when I don't specify a setpoint SOC for my battery bank? The battery Setpoint State of Charge (SOC) has no effect on whether HOMER charges the battery. The setpoint SOC only affects how long HOMER continues to charge the battery. The definition of the cycle chargi

What are rules or how do we find out the rules within Homer that determine the operation of the gensets and the charging and discharging of the batteries? HOMER operates the dispatchable power sources (generators, battery) in such a way as to minimize cost. Each hour, HOMER looks at the available dispatchable power sources and chooses to opera

Product: HOMER Pro and HOMER Grid The dispatch strategy in HOMER Pro and HOMER Grid specify how the HOMER engine operates storage and power sources to serve the load. It turns generators and batteries off and on, and it chooses how much power they produce or consume in each timestep to serve the load. HOMER Pro includes several controllers that yo

Is there a battery management strategy that would reflect that the storage of excess electricity should not impact the cost/kW of battery energy? The system configuration whose operation you describe, where the diesel charges the battery in the first few hours of the year, uses the cycle charging strategy. Under the cycle charging strategy, th

Is there a setting which I am missing which allows battreies to ofset peak load and diesels can run at lower level? In a diesel/battery system, whatever energy is in the batteries must come from the diesel. The AC-AC roundtrip efficiency (through the rectifier, into and out of the battery, back through the inverter to the load) in your system

How is the generator controlled to give either as much power to meet the load or to supply the battery as well. Is the generator speed regulated in the model or does the model assume that the battery can be disconnected from the system? Under load following, the generator produces just enough power to serve the load. The generator does not del

I don't understand why HOMER doesn't start the GenSet automatically with the Optimized Mode. HOMER's dispatch logic is 'optimized' in the sense that it attempts to operate the system so as to minimize cost, but with the limitation that it does not attempt to predict the future. The case you describe is one where some simple prediction could le

Do you think it's possible to move the results to the future in a way that considers the future value of money correctly? HOMER does account for the time value of money, if that's what you mean, it just doesn't allow the system to change over time. It would be hard work, but you could perform separate HOMER runs for each five-year segment of t

Product: HOMER Pro and HOMER Grid When importing a data load file to HOMER consisting of a hourly data of 8,784 values (a year of 366 days), do you have to take under consideration a new TIME STEP? HOMER assumes a 365-day year, so before you import data from a leap year you have to change it from 366 to 365 days. I think the best way to do t

What is the difference between Load Following and Cycle Charging with a set point of 0%? Even if the setpoint state of charge is 0% or you choose not to apply a setpoint, there is still a difference between load following and cycle charging. Under cycle charging, whenever the generators operate they run at full blast (or as close as they can

How do you get HOMER to model a medium penetration system, one where you have to have a diesel running at all times, whether or not the capacity is needed, and it must be running at least at it's minimum allowable load? Yes, you can force the system to operate at least one generator by setting the operating reserve as a function of wind power o

My wind data is in 10 minute increments and I’m wondering if I will have to synthesize it if I would like to go down to single minute time steps? Or is that something HOMER does automatically? If you import 10-minute wind data and then set the simulation time step to 1 minute (in the System Control Inputs window) HOMER will simply chop each 10-

Does Homer consider that the entire user load has to be met from the battery, even if there is enough solar energy available? What I mean is if Homer does take into account that a charge regulator allows energy to flow from the PV to the user AND into the battery? In a PV-battery system, if the PV power is more than sufficient to serve the load, H

Product: HOMER Pro To use the MATLAB Link module in HOMER Pro, you will need the following: (1) HOMER Pro version 3.7 or above (2) Installation of MATLAB - You can use 32-bit MATLAB with 32-bit HOMER Pro, & the 64-bit MATLAB with 64-bit HOMER Pro - You do not need to install any additional modules/add-ons in your MATLAB installation (3) A lic

After running the simulation, batteries operate more than fuel cells. I want to ask you why this has happened. For me, the only explanation is that because HOMER takes economical data into account and because batteries have lower initial as well as O&M costs than the fuel cells, they are more advantageous to operate. Is this explanation correc

I have a question regarding how the load that cannot be met by primary renewable devices (like a wind turbine or PV array) is met. According to the load following strategy, it seems that multiple devices (generators, batteries, etc.) can meet a given demand simultaneously and optimally. By this I mean that the load can be shared in an optimal way

Not all of the time series data sets you import into a particular HOMER file need have the same time step. You might import, for example, hourly solar resource data, 10-minute wind resource data, and 15-minute load data. On the System Control window you set the simulation time step.

If I've gathered correctly, Homer looks at system's operation during one year. That's not quite true. HOMER does an analysis of the economics of the system over the entire project lifetime, which by default is 25 years. But it does not actually simulate 25 years of operation. Rather, it simulates one year of operation and assumes that that o