I encountered a problem with the NIntegrate function while simulating a physical situation. The expression is quite messy, but it is just an integration over a polynomial so it should be possible. I want to integrate the function over kP and Energy, and then plot the results with T varying from 0 to 10. 

        simplifiednumThermalConductivityIntegrationContentPosSpin=
    {-((4.24285*10^44 (1.00032*10^-30 - 
        6.371*10^-31 Energy)^2 (1.3836*10^6 + 1. Energy^6 + 
        259200. kP^4 + 
        Energy^5 (0.000999182 Sqrt[-9 + 1000000 Energy^2] - 
           1.41159 kP^2) - 
        598856. Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
         2.3104 + 1.47148 Energy - kP^2] + 
        kP^2 (-1.19771*10^6 + 
           259200. Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2]) + 
        Energy^2 (-2.306*10^11 - 
           1.26035*10^-8 Sqrt[-9 + 1000000 Energy^2] - 
           4.32*10^10 kP^4 + 
           3.32698*10^10 Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2] - 
           3.72529*10^-9 Sqrt[-9 + 1000000 Energy^2] Sqrt[
            2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2] + 
           kP^2 (1.99619*10^11 - 
              1.44*10^10 Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
               2.3104 + 1.47148 Energy - kP^2])) + 
        Energy^4 (9.35396*10^10 - 1.5 kP^4 - 
           1.68212 Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2] - 
           0.00146484 Sqrt[-9 + 1000000 Energy^2] Sqrt[
            2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2] + 
           kP^2 (2. - 0.000403313 Sqrt[-9 + 1000000 Energy^2] - 
              1.88631 Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
               2.3104 + 1.47148 Energy - kP^2])) + 
        Energy (2.91038*10^-11 - 
           7.68665*10^7 Sqrt[-9 + 1000000 Energy^2] - 
           1.44*10^7 Sqrt[-9 + 1000000 Energy^2] kP^4 + 
           1.16415*10^-10 Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2] - 
           3.32698*10^7 Sqrt[-9 + 1000000 Energy^2] Sqrt[
            2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2] + 
           1.44*10^7 Sqrt[-9 + 1000000 Energy^2]
             kP^2 (4.6208 + 
              1. Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
               2.3104 + 1.47148 Energy - kP^2])) + 
        Energy^3 (-9.37702*10^-6 + 
           3.11799*10^7 Sqrt[-9 + 1000000 Energy^2] - 
           0.000476971 Sqrt[-9 + 1000000 Energy^2] kP^4 - 
           7.62939*10^-6 Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2] + 
           kP^2 (0.0000145193 + 
              0.000976563 Sqrt[-9 + 1000000 Energy^2] + 
              
              0.00146484 Sqrt[-9 + 1000000 Energy^2] Sqrt[
               2.3104 - 1.47148 Energy - kP^2] Sqrt[
               2.3104 + 1.47148 Energy - kP^2]))) Sech[(
       5800.46 (-1.57011 + Energy))/
       T])/((1. Energy - 
        0.001 Sqrt[-9 + 1000000 Energy^2]) (1. Energy + 
        0.001 Sqrt[-9 + 1000000 Energy^2]) (Sqrt[-9 + 
          1000000 Energy^2] (-0.0023104 + 0.001 kP^2 + 
           0.003 Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2]) + 
        Energy (2.3104 - 8.88178*10^-20 Sqrt[-9 + 1000000 Energy^2] - 
           1. kP^2 + 
           1. Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2])) (Sqrt[-9 + 
          1000000 Energy^2] (-0.0023104 + 0.001 kP^2 + 
           0.003 Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2]) + 
        Energy (2.3104 + 1.77636*10^-19 Sqrt[-9 + 1000000 Energy^2] - 
           1. kP^2 + 
           1. Sqrt[2.3104 - 1.47148 Energy - kP^2] Sqrt[
            2.3104 + 1.47148 Energy - kP^2])) T^2))}


Now, trying the following line, I get the `NIntegrate::inumr` error in the headline:

    answer = NIntegrate[simplifiednumThermalConductivityIntegrationContentPosSpin,
    {kP, 0, 1}, {Energy, 0, Infinity}]

I have also tried to integrate the energy only from 0 to 0.55, but that won't solve the problem. 

Do any of you have any tips as to what I should try to be able to plot this? Any help will be greatly appreciated!