The Smart Home security system for house door locks with the face of the homeowner uses ESP32Cam as a face detection camera in case of problems that occur with a lack of home security so that criminals can break into the door of the house. So the need for a tool that can increase the security of the door so that it is not easily opened. The face protection process is in accordance with what is input to the system camera ESP32Cam; the relay automatically gives the command to open the door to the magnetic solenoid so that the door is opened. Testing tools through the method experimental (trial and error) the tool works well and helps homeowners in increasing home security by 97% suitable for use and functioning with a distance of 5-10 cm.

Inovasi pengembangan Pembangkit Listrik Tenaga Mikro Hidro (PLTMH) terus dikembangkan mengingat kebutuhan akan energi listrik terus meningkat. Hal ini perlu didukung adanya media pembelajaran untuk mencari solusi alternatif permasalahan dalam mengatasi kebutuhan energi tersebut. Penelitian ini mendesain dan mengembangkan pembuatan PLTMH dengan back flow water system. Implementasi sistem berupa prototipe yang dapat digunakan sebagai media pembelajaran mahasiswa dan alat uji energi alternatif hidro. Metode perancangan dan manufaktur menggunakan metode Pahl & Beitz dan pengujian menggunakan metode eksperimen dengan cara pengamatan dan pencatatan data-data yang ditunjukkan pada alat ukur.  Pengujian dilakukan dua tahap, pengujian pertama pada putaran kincir dan transmisi, pengujian kedua pada putaran dinamo dan voltase. Hasil pengujian menunjukkan bahwa sistem yang dirancang memiliki unjuk kerja yang baik.

The illegal gold mine in kuantan singingi district was a very difficult problem. Raids on illegal gold miners have also been made, but have not been able to cause deterrent effects for the perpetrators. This was due to the lack of public knowledge of the effect caused by illegal gold mining, one of the dangers feared is mercury contamination. This study aims to analyze the mercury contents found in the water in the area of gold mining in the kuantan river, Kuantan singingi district, Riau. Determination of mercury content in the sample was conducted using Atomic Absorption Spectrophotometer (AAS). The results of the analysis found that the mercury content in the sample sites 1 and 4 was 0.0407 mg / L and 0.0117 mg / L, which means that exceeds the limit value of the provisions of 0.002 mg / L (PP No. 82 of 2001).

Hybrid power is a combination of two or more alternative energy sources to produce high-efficiency electrical energy under different load conditions. Hybrid energy research has been carried out through previous research, including combining solar and wind, solar and biomass, hydro, thermal, wind, solar and solar with thermoelectric generators. This study designs a hybrid power plant model based on solar and hydroelectricity with a water circulation system. Water falling from the upper reservoir into the lower reservoir is returned to the upper reservoir using an electric pump, and this study is a development of previous research related to alternative hydropower. The method used in this study is the Pahl and Beitz method, including design sketches, material selection, fabrication, and testing phases. The solar cell frame design produced by the Pahl and Beitz process is 100 cm high and 65 cm wide, and the module type used is a 3-piece polycrystalline module. The average power output produced by the 3 solar panels to the cells was 19.76 watts. The test produced 850 watts of total hybrid power, 600 watts DC from solar, and 250 watts DC from hydro.