text: main aaj kal soch rahi thi ki agar sab log apne gharon ke liye energy-efficient appliances istemal karein,toh kitni energy bachegi, kya tumhe bhi yeh idea acha laga?haan, aur yeh toh long-term investment bhi hai, par mujhe samajh nahi aata ki kaunse appliances sabse zyada efficient hain, kya tumne kabhi research kiya hai?