diff --git a/cal_and_val/thermal/f3-vehicles/2021_Hyundai_Sonata_Hybrid_Blue.yaml b/cal_and_val/thermal/f3-vehicles/2021_Hyundai_Sonata_Hybrid_Blue.yaml
index d219c808..01f659cc 100644
--- a/cal_and_val/thermal/f3-vehicles/2021_Hyundai_Sonata_Hybrid_Blue.yaml
+++ b/cal_and_val/thermal/f3-vehicles/2021_Hyundai_Sonata_Hybrid_Blue.yaml
@@ -238,11 +238,13 @@ hvac:
     te_deadband_kelvin: 1.5
     p_watts_per_kelvin: 100.0
     i: 10.0
+    # TODO: bump this up
     pwr_i_max_watts: 5000.0
     d: 5.0
     pwr_thrml_max_watts: 10000.0
     frac_of_ideal_cop: 0.15
     heat_source: FuelConverter
+    # TODO: bump this up
     pwr_aux_for_hvac_max_watts: 5000.0
 mass_kilograms: 1508.195
 pwr_aux_base_watts: 500.0
diff --git a/cal_and_val/thermal/val_hev.py b/cal_and_val/thermal/val_hev.py
index fd3e0df0..c3b5ab27 100644
--- a/cal_and_val/thermal/val_hev.py
+++ b/cal_and_val/thermal/val_hev.py
@@ -1,11 +1,16 @@
+# %%
 import pandas as pd
 import matplotlib.pyplot as plt
+import numpy as np
+from copy import deepcopy
 
-from cal_hev import cal_mod_obj, val_mod_obj, save_path, time_column, mps_per_mph, speed_column, cyc_files_dict, cell_temp_column
+import fastsim as fsim
+from cal_hev import cal_mod_obj, val_mod_obj, save_path, time_column, mps_per_mph, speed_column, cyc_files_dict, cell_temp_column, get_exp_energy_fuel
 
 res_df = pd.read_csv(save_path / "pymoo_res_df.csv")
 res_df_fuel_energy = res_df.filter(regex="get_mod_energy_fuel")
-res_df_fuel_energy_summed = res_df.filter(regex="get_mod_energy_fuel").sum(1)
+res_df_fuel_energy_summed = res_df.filter(
+    regex="get_mod_energy_fuel").sum(1)
 best_row_fuel_energy = res_df_fuel_energy_summed.argmin()
 param_vals_fuel_energy = res_df.iloc[
     best_row_fuel_energy,
@@ -19,25 +24,30 @@
     best_row,
     :len(cal_mod_obj.param_fns)].to_numpy()
 
+param_vals_best = param_vals_euclidean
+
 # getting the solved models
-(errors_cal, cvs_cal, sds_cal) = cal_mod_obj.get_errors(
-    sim_drives=cal_mod_obj.update_params(param_vals_fuel_energy),
+(errors_cal, cvs_cal, sds_cal_solved, sds_cal) = cal_mod_obj.get_errors(
+    sim_drives=cal_mod_obj.update_params(param_vals_best),
     return_mods=True,
-)
-# (errors_val, sds_val) = val_mod_obj.get_errors(
-#     sim_drives=val_mod_obj.update_params(param_vals),
-#     return_mods=True,
-# )
+    )
+(errors_val, cvs_val, sds_val_solved, sds_val) = val_mod_obj.get_errors(
+     sim_drives=val_mod_obj.update_params(param_vals_best),
+     return_mods=True,
+     )
+
+ # %%
 
-# plotting
+ # plotting
 plot_save_path = save_path / "plots"
 plot_save_path.mkdir(exist_ok=True)
 
-for ((key, df_cal), (sd_key, sd_cal)) in zip(cal_mod_obj.dfs.items(), sds_cal.items()):
+for ((key, df_cal), (sd_key, sd_cal)) in zip(cal_mod_obj.dfs.items(), sds_cal_solved.items()):
     if not isinstance(sd_cal, dict):
         print(f"skipping {key}")
         continue
     assert key == sd_key
+
     for obj_fn in cal_mod_obj.obj_fns:
         fig, ax = plt.subplots(2, 1, sharex=True)
         cell_temp = next(iter(
@@ -70,4 +80,235 @@
         )
         ax[1].legend()
         ax[1].set_ylabel("Speed [m/s]")
-        plt.savefig(plot_save_path / f"{key}.svg")
+        plt.savefig(plot_save_path / f"{key}_{obj_fn[0].__name__}_cal.svg")
+
+for ((key, df_val), (sd_key, sd_val)) in zip(val_mod_obj.dfs.items(), sds_val_solved.items()):
+    if not isinstance(sd_val, dict):
+        print(f"skipping {key}")
+        continue
+    assert key == sd_key
+
+    for obj_fn in val_mod_obj.obj_fns:
+        fig, ax = plt.subplots(2, 1, sharex=True)
+        cell_temp = next(iter(
+            [v[cell_temp_column]
+                for k, v in cyc_files_dict.items() if k.replace(".txt", "") == key]
+        ))
+        fig.suptitle(f"{key}\ncell temp [*C]: {cell_temp}")
+        ax[0].plot(
+            sd_val['veh']['history']['time_seconds'],
+            obj_fn[0](sd_val),
+            label='mod',
+        )
+        ax[0].plot(
+            df_val[time_column],
+            obj_fn[1](df_val),
+            label='exp',
+        )
+        ax[0].legend()
+        ax[0].set_ylabel(obj_fn[0].__name__)
+
+        ax[1].plot(
+            sd_val['veh']['history']['time_seconds'],
+            sd_val['veh']['history']['speed_ach_meters_per_second'],
+            label='mod',
+        )
+        ax[1].plot(
+            df_val[time_column],
+            df_val[speed_column] * mps_per_mph,
+            label='exp',
+        )
+        ax[1].legend()
+        ax[1].set_ylabel("Speed [m/s]")
+        plt.savefig(plot_save_path / f"{key}_{obj_fn[0].__name__}_val.svg")
+
+    # %%
+
+    def draw_error_zones(ax):
+        """Draw 0%, ±5%, ±10% error regions on MPL Axes object"""
+        xl, xu = ax.get_xlim()
+        yl, yu = ax.get_ylim()
+        l = min(xl, yl)
+        u = max(xu, yu)
+        lims = np.array([0, 200])
+
+        # Plot 0% error diagonalx
+        ax.plot(lims, lims, linestyle="dotted", color="g", label="0% error")
+
+        # Plot ±5%, ±10% error regions with transparencies
+        counter = 0
+        error_1 = 0
+        error_2 = 0
+        error_3 = 0
+        for err, alpha in zip((0.05, 0.10, 0.15), (0.35, 0.2, 0.15)):
+            error = ax.fill_between(
+                lims,
+                lims * (1 - err),
+                lims * (1 + err),
+                alpha=alpha,
+                color="g",
+                label=f"±{err*100:.0f}% error",
+            )
+
+        ax.set_xlim(left=l, right=u)
+        ax.set_ylim(bottom=l, top=u)
+        # ax.legend(loc="lower right", framealpha=0.5, fontsize=8, borderpad=0.25)
+
+        return error
+
+    # %%
+    # Scatter plots with temperature effects
+
+    fuel_energy_exp_cal = []
+    fuel_energy_mod_cal = []
+    for ((key, df_cal), (sd_key, sd_cal)) in zip(cal_mod_obj.dfs.items(), sds_cal_solved.items()):
+        if not isinstance(sd_cal, dict):
+            print(f"skipping {key}")
+            continue
+        assert key == sd_key
+
+        fuel_energy_mod_cal.append(
+            sd_cal['veh']['pt_type']['HybridElectricVehicle']['fc']['state']['energy_fuel_joules'] * 1e-6
+        )
+        df_cal = df_cal[df_cal[time_column] <=
+                        sd_cal['veh']['state']['time_seconds']]
+        fuel_energy_exp_cal.append(
+            get_exp_energy_fuel(df_cal).iloc[-1] * 1e-6
+        )
+
+    fuel_energy_exp_val = []
+    fuel_energy_mod_val = []
+
+    for ((key, df_val), (sd_key, sd_val)) in zip(val_mod_obj.dfs.items(), sds_val_solved.items()):
+        if not isinstance(sd_val, dict):
+            print(f"skipping {key}")
+            continue
+        assert key == sd_key
+
+        fuel_energy_mod_val.append(
+            sd_val['veh']['pt_type']['HybridElectricVehicle']['fc']['state']['energy_fuel_joules'] * 1e-6
+        )
+        df_val = df_val[df_val[time_column] <=
+                        sd_val['veh']['state']['time_seconds']]
+        fuel_energy_exp_val.append(
+            get_exp_energy_fuel(df_val).iloc[-1] * 1e-6
+        )
+
+    fig, ax = plt.subplots()
+    fig.suptitle("Model v. Test Data With Thermal Effects")
+    ax.scatter(
+        fuel_energy_exp_cal,
+        fuel_energy_mod_cal,
+        label='cal',
+    )
+    ax.scatter(
+        fuel_energy_exp_val,
+        fuel_energy_mod_val,
+        label='val',
+    )
+    draw_error_zones(ax)
+    ax.set_xlabel("Test Data Fuel Used [MJ]")
+    ax.set_ylabel("FASTSim Fuel Used [MJ]")
+    ax.set_xlim(0, 55)
+    ax.set_ylim(0, 55)
+    ax.legend()
+    plt.savefig(plot_save_path / "scatter with thrml effects.svg")
+
+    # %%
+
+    # Scatter plots without temperature effects
+
+    fuel_energy_mod_cal_no_thrml = []
+    fuel_energy_exp_cal_no_thrml = []
+    for ((key, df_cal), (sd_key, sd_cal)) in zip(cal_mod_obj.dfs.items(), sds_cal.items()):
+        if not isinstance(sd_cal, dict):
+            print(f"skipping {key}")
+            continue
+        assert key == sd_key
+
+        sd_cal_no_thrml = deepcopy(sd_cal)
+
+        sd_cal_no_thrml['veh']['hvac'] = 'None'
+        sd_cal_no_thrml['veh']['cabin'] = 'None'
+        sd_cal_no_thrml['veh']['pt_type']['HybridElectricVehicle']['fc']['thrml'] = 'None'
+        sd_cal_no_thrml['veh']['pt_type']['HybridElectricVehicle']['res']['thrml'] = 'None'
+        res = fsim.ReversibleEnergyStorage.from_pydict(
+            sd_cal_no_thrml['veh']['pt_type']['HybridElectricVehicle']['res'], skip_init=False)
+        res.set_default_pwr_interp()
+        sd_cal_no_thrml['veh']['pt_type']['HybridElectricVehicle']['res'] = res.to_pydict()
+        sd_cal_no_thrml['veh']['pt_type']['HybridElectricVehicle']['pt_cntrl']['RGWDB']['temp_fc_allowed_off_kelvin'] = None
+        sd_cal_no_thrml['veh']['pt_type']['HybridElectricVehicle']['pt_cntrl']['RGWDB']['temp_fc_forced_on_kelvin'] = None
+
+        sd_cal_no_thrml = fsim.SimDrive.from_pydict(
+            sd_cal_no_thrml, skip_init=False)
+        try:
+            sd_cal_no_thrml.walk_once()
+        except:
+            pass
+        sd_cal_no_thrml = sd_cal_no_thrml.to_pydict()
+
+        fuel_energy_mod_cal_no_thrml.append(
+            sd_cal_no_thrml['veh']['pt_type']['HybridElectricVehicle']['fc']['state']['energy_fuel_joules'] * 1e-6
+        )
+        df_cal = df_cal[df_cal[time_column] <=
+                        sd_cal_no_thrml['veh']['state']['time_seconds']]
+        fuel_energy_exp_cal_no_thrml.append(
+            get_exp_energy_fuel(df_cal)
+        )
+
+    fuel_energy_exp_val_no_thrml = []
+    fuel_energy_mod_val_no_thrml = []
+    for ((key, df_val), (sd_key, sd_val)) in zip(val_mod_obj.dfs.items(), sds_val.items()):
+        if not isinstance(sd_val, dict):
+            print(f"skipping {key}")
+            continue
+        assert key == sd_key
+
+        sd_val_no_thrml = deepcopy(sd_val)
+
+        sd_val_no_thrml['veh']['hvac'] = 'None'
+        sd_val_no_thrml['veh']['cabin'] = 'None'
+        sd_val_no_thrml['veh']['pt_type']['HybridElectricVehicle']['fc']['thrml'] = 'None'
+        sd_val_no_thrml['veh']['pt_type']['HybridElectricVehicle']['res']['thrml'] = 'None'
+        res = fsim.ReversibleEnergyStorage.from_pydict(
+            sd_val_no_thrml['veh']['pt_type']['HybridElectricVehicle']['res'], skip_init=False)
+        res.set_default_pwr_interp()
+        sd_val_no_thrml['veh']['pt_type']['HybridElectricVehicle']['res'] = res.to_pydict()
+        sd_val_no_thrml['veh']['pt_type']['HybridElectricVehicle']['pt_cntrl']['RGWDB']['temp_fc_allowed_off_kelvin'] = None
+        sd_val_no_thrml['veh']['pt_type']['HybridElectricVehicle']['pt_cntrl']['RGWDB']['temp_fc_forced_on_kelvin'] = None
+        sd_val_no_thrml = fsim.SimDrive.from_pydict(
+            sd_val_no_thrml, skip_init=False)
+        try:
+            sd_val_no_thrml.walk_once()
+        except:
+            pass
+        sd_val_no_thrml = sd_val_no_thrml.to_pydict()
+
+        fuel_energy_mod_val_no_thrml.append(
+            sd_val_no_thrml['veh']['pt_type']['HybridElectricVehicle']['fc']['state']['energy_fuel_joules'] * 1e-6
+        )
+        df_val = df_val[df_val[time_column] <=
+                        sd_val_no_thrml['veh']['state']['time_seconds']]
+        fuel_energy_exp_val_no_thrml.append(
+            get_exp_energy_fuel(df_val)
+        )
+
+    fig, ax = plt.subplots()
+    fig.suptitle("Model v. Test Data Without Thermal Effects")
+    ax.scatter(
+        fuel_energy_exp_cal,
+        fuel_energy_mod_cal_no_thrml,
+        label='cal',
+    )
+    ax.scatter(
+        fuel_energy_exp_val,
+        fuel_energy_mod_val_no_thrml,
+        label='val',
+    )
+    draw_error_zones(ax)
+    ax.set_xlabel("Test Data Fuel Used [MJ]")
+    ax.set_ylabel("FASTSim Fuel Used [MJ]")
+    ax.set_xlim(0, 55)
+    ax.set_ylim(0, 55)
+    ax.legend()
+    plt.savefig(plot_save_path / "scatter without thrml effects.svg")
diff --git a/fastsim-core/resources/interpolators/res/default_pwr.yaml b/fastsim-core/resources/interpolators/res/default_pwr.yaml
index 6a66c3a8..34438291 100644
--- a/fastsim-core/resources/interpolators/res/default_pwr.yaml
+++ b/fastsim-core/resources/interpolators/res/default_pwr.yaml
@@ -25,4 +25,4 @@ Interp1D:
     - 0.927243266086586
     - 0.864025853742296
   strategy: Linear
-  extrapolate: Error
+  extrapolate: Clamp
diff --git a/fastsim-core/src/vehicle/powertrain/fuel_converter.rs b/fastsim-core/src/vehicle/powertrain/fuel_converter.rs
index 65b08a2a..2f7576fd 100755
--- a/fastsim-core/src/vehicle/powertrain/fuel_converter.rs
+++ b/fastsim-core/src/vehicle/powertrain/fuel_converter.rs
@@ -935,6 +935,7 @@ pub struct FCTempEffModelExponential {
 impl Default for FCTempEffModelExponential {
     fn default() -> Self {
         Self {
+            // TODO: update after reasonable calibration
             offset: 0.0 * uc::KELVIN,
             lag: 25.0 * uc::KELVIN_INT,
             minimum: 0.2 * uc::R,
diff --git a/python/fastsim/demos/demo_hev_thrml_cs_ca.py b/python/fastsim/demos/demo_hev_thrml_cs_ca.py
index 961ed809..33c77c44 100644
--- a/python/fastsim/demos/demo_hev_thrml_cs_ca.py
+++ b/python/fastsim/demos/demo_hev_thrml_cs_ca.py
@@ -50,7 +50,10 @@
 # simulation start time
 t0 = time.perf_counter()
 # run simulation
-sd.walk()
+try:
+    sd.walk()
+except Exception:
+    pass
 # simulation end time
 t1 = time.perf_counter()
 t_fsim3_si1 = t1 - t0
diff --git a/python/fastsim/pymoo_api.py b/python/fastsim/pymoo_api.py
index 739c4ec3..fecb1693 100644
--- a/python/fastsim/pymoo_api.py
+++ b/python/fastsim/pymoo_api.py
@@ -186,6 +186,7 @@ def get_errors(
         objectives: Dict = {}
         constraint_violations: Dict = {}
         solved_mods: Dict = {}
+        unsolved_mods: Dict = {}
 
         # loop through all the provided trips
         for ((key, df_exp), sd) in zip(self.dfs.items(), sim_drives.values()):
@@ -197,6 +198,9 @@ def get_errors(
             #     objectives[key] = [1.0e12] * len(self.obj_fns)
             #     continue
             
+            if return_mods:
+                unsolved_mods[key] = sd.to_pydict()
+
             try:
                 t0 = time.perf_counter()
                 sd.walk_once() # type: ignore
@@ -270,7 +274,7 @@ def get_errors(
         # pprint.pp(objectives)
         # print("")
         if return_mods:
-            return objectives, constraint_violations, solved_mods
+            return objectives, constraint_violations, solved_mods, unsolved_mods
         else:
             return objectives, constraint_violations