diff --git a/tgui/packages/tgui/components/Chart.jsx b/tgui/packages/tgui/components/Chart.tsx
similarity index 53%
rename from tgui/packages/tgui/components/Chart.jsx
rename to tgui/packages/tgui/components/Chart.tsx
index 1e856135c659..205dc6fbec1a 100644
--- a/tgui/packages/tgui/components/Chart.jsx
+++ b/tgui/packages/tgui/components/Chart.tsx
@@ -5,28 +5,57 @@
  */
 
 import { map, zipWith } from 'common/collections';
-import { Component, createRef } from 'react';
-import { Box } from './Box';
+import { Component, createRef, RefObject } from 'react';
 
-const normalizeData = (data, scale, rangeX, rangeY) => {
+import { Box, BoxProps } from './Box';
+
+type Props = {
+  data: number[][];
+} & Partial<{
+  fillColor: string;
+  rangeX: [number, number];
+  rangeY: [number, number];
+  strokeColor: string;
+  strokeWidth: number;
+}> &
+  BoxProps;
+
+type State = {
+  viewBox: [number, number];
+};
+
+type Point = number[];
+type Range = [number, number];
+
+const normalizeData = (
+  data: Point[],
+  scale: number[],
+  rangeX?: Range,
+  rangeY?: Range,
+) => {
   if (data.length === 0) {
     return [];
   }
+
   const min = zipWith(Math.min)(...data);
   const max = zipWith(Math.max)(...data);
+
   if (rangeX !== undefined) {
     min[0] = rangeX[0];
     max[0] = rangeX[1];
   }
+
   if (rangeY !== undefined) {
     min[1] = rangeY[0];
     max[1] = rangeY[1];
   }
-  const normalized = map((point) => {
-    return zipWith((value, min, max, scale) => {
+
+  const normalized = map((point: Point) => {
+    return zipWith((value: number, min: number, max: number, scale: number) => {
       return ((value - min) / (max - min)) * scale;
     })(point, min, max, scale);
   })(data);
+
   return normalized;
 };
 
@@ -39,21 +68,18 @@ const dataToPolylinePoints = (data) => {
   return points;
 };
 
-class LineChart extends Component {
-  constructor(props) {
+class LineChart extends Component<Props> {
+  ref: RefObject<HTMLDivElement>;
+  state: State;
+
+  constructor(props: Props) {
     super(props);
     this.ref = createRef();
     this.state = {
       // Initial guess
       viewBox: [600, 200],
     };
-    this.handleResize = () => {
-      const element = this.ref.current;
-      if (!element) return;
-      this.setState({
-        viewBox: [element.offsetWidth, element.offsetHeight],
-      });
-    };
+    this.handleResize = this.handleResize.bind(this);
   }
 
   componentDidMount() {
@@ -65,6 +91,16 @@ class LineChart extends Component {
     window.removeEventListener('resize', this.handleResize);
   }
 
+  handleResize = () => {
+    const element = this.ref.current;
+    if (!element) {
+      return;
+    }
+    this.setState({
+      viewBox: [element.offsetWidth, element.offsetHeight],
+    });
+  };
+
   render() {
     const {
       data = [],
@@ -87,32 +123,32 @@ class LineChart extends Component {
       normalized.push([-strokeWidth, first[1]]);
     }
     const points = dataToPolylinePoints(normalized);
+    const divProps = { ...rest, className: '', ref: this.ref };
+
     return (
       <Box position="relative" {...rest}>
-        {(props) => (
-          <div ref={this.ref} {...props}>
-            <svg
-              viewBox={`0 0 ${viewBox[0]} ${viewBox[1]}`}
-              preserveAspectRatio="none"
-              style={{
-                position: 'absolute',
-                top: 0,
-                left: 0,
-                right: 0,
-                bottom: 0,
-                overflow: 'hidden',
-              }}
-            >
-              <polyline
-                transform={`scale(1, -1) translate(0, -${viewBox[1]})`}
-                fill={fillColor}
-                stroke={strokeColor}
-                strokeWidth={strokeWidth}
-                points={points}
-              />
-            </svg>
-          </div>
-        )}
+        <Box {...divProps}>
+          <svg
+            viewBox={`0 0 ${viewBox[0]} ${viewBox[1]}`}
+            preserveAspectRatio="none"
+            style={{
+              position: 'absolute',
+              top: 0,
+              left: 0,
+              right: 0,
+              bottom: 0,
+              overflow: 'hidden',
+            }}
+          >
+            <polyline
+              transform={`scale(1, -1) translate(0, -${viewBox[1]})`}
+              fill={fillColor}
+              stroke={strokeColor}
+              strokeWidth={strokeWidth}
+              points={points}
+            />
+          </svg>
+        </Box>
       </Box>
     );
   }
diff --git a/tgui/packages/tgui/interfaces/PowerMonitor.jsx b/tgui/packages/tgui/interfaces/PowerMonitor.jsx
index 0e317e72d201..ece815d649c2 100644
--- a/tgui/packages/tgui/interfaces/PowerMonitor.jsx
+++ b/tgui/packages/tgui/interfaces/PowerMonitor.jsx
@@ -35,7 +35,7 @@ export const PowerMonitor = () => {
 
 export const PowerMonitorContent = (props) => {
   const { data } = useBackend();
-  const { history } = data;
+  const { history = { supply: [], demand: [] } } = data;
   const [sortByField, setSortByField] = useLocalState('sortByField', null);
   const supply = history.supply[history.supply.length - 1] || 0;
   const demand = history.demand[history.demand.length - 1] || 0;
@@ -87,7 +87,7 @@ export const PowerMonitorContent = (props) => {
           </Section>
         </Flex.Item>
         <Flex.Item mx={0.5} grow={1}>
-          <Section position="relative" height="100%">
+          <Section position="relative" fill>
             <Chart.Line
               fillPositionedParent
               data={supplyData}