One of the key aspects of sustainability in web development is minimising resource consumption. In React apps, developers can implement various techniques to reduce the application’s overall footprint:

• Virtual DOM and Efficient Rendering: React’s virtual DOM efficiently updates and renders only the necessary components, reducing unnecessary re-renders and enhancing performance.

• Lazy Loading: Implementing lazy loading techniques allows components, images, and other assets to be loaded only when they are required. This approach minimizes initial loading times and conserves bandwidth.

 import React, { Suspense, lazy } from 'react';
 const LazyComponent = lazy(() => import('./LazyComponent'));

• Code Minification and Compression: By minifying and compressing JavaScript and CSS files, developers can significantly reduce their size, resulting in faster loading times and reduced bandwidth consumption.

       React.memo, useMemo, useCallback

Sustainable web development also includes creating applications that are accessible and user-friendly. By ensuring proper accessibility features and intuitive design principles, React apps can provide an inclusive experience for all users. Some examples include:

• Semantic HTML: Using semantic HTML elements in React components improves accessibility and helps assistive technologies interpret and navigate the application more effectively.
• Keyboard Navigation: Enabling keyboard navigation and focus management in React apps allows users to navigate through the application without relying solely on a mouse or touch input, ensuring inclusivity.
• Responsive Design: Designing React apps with responsive layouts that adapt to different screen sizes and devices enhances user experience and reduces the need for excessive energy-consuming scrolling or zooming.

Energy consumption is a critical factor in sustainability, and web development can contribute to reducing energy usage. In React apps, developers can take steps to optimize energy efficiency:

• Client-Side Caching: Implementing client-side caching techniques, such as leveraging browser caching and utilising local storage, reduces the number of server requests, resulting in lower energy consumption.

 (useSWR or React Query)

• Efficient Network Requests: Minimising the number of network requests and optimising data transfer can significantly reduce the energy required to load a React app. Batching requests through axios.

 import axios from 'axios';
 
 async function fetchData() {
const [response1, response2] = await Promise.all([
  axios.get('/api/data1'),
  axios.get('/api/data2')
]);

• Background Processes and Timers: Avoiding unnecessary background processes and minimising the usage of timers can reduce energy consumption on both client and server sides. By optimising the timing and frequency of such operations, React apps can be more sustainable.

Apart from technical optimisations, sustainable web development also emphasises the importance of thoughtful design and user experience choices. React apps can incorporate sustainability principles into their design:

• Dark Mode: Introducing a dark mode option in React apps can provide users with an energy-saving alternative. Dark mode reduces the energy consumption of devices with OLED or AMOLED displays, as fewer pixels need to be lit up.

 const [theme, setTheme] = React.useState('light');

 const toggleTheme = () => {
   setTheme(theme === 'light' ? 'dark' : 'light');
 };

Reference: link