Genetic algorithm optimization

Hi everybody, I want to make an optimization that with discrete variables. I found that I have to use the genetic algorithm, but before that I want to understand if I can realize what I have in mind. I want to do somenthing like this:

function to minimize:

Cost = c1*x(1) + c2*x(2) + c3*x(3) + c4*x(4);

x(i) are the variables
constrains:

LPSP < 0.05

tank(t,1) > 0

1) first constrain
where t is the time every 10 minutes in one year (total = 52560)

Pgen(t) = x(1)*P1(t) + x(2)*P2(t) + x(3)*P3(t) + x(4)*P4(t) - Pload(t);

totalTime = 52560;
time = 0;
for t = 1:totalTime
    if (Pgen(t) < 0)
        time = time + 1;
    end
end
LPSP = time/totalTime;

2) second constrain

for t = 1:totalTime
    if (Pgen(t) > 0)
        tank(t,1) = tank(t-1,1) + Prod;
    else
        tank(t,1) = tank(t-1,1) - Consume;
    end
end

Prod and Consume are quantities that is found resolving a non linear equation that depence on the Pgen

Prod = function(Pgen)

Consume = function(Pgen)

Thanks