First and foremost, securing the electoral process is fundamental to public trust in democratic governance. Traditional voting systems, from paper ballots to electronic machines, have long survived despite vulnerabilities to tampering, limited auditability, and an absence of strong end-to-end verifiability. To address these, this paper proposes the Secure and Transparent Blockchain Voting Algorithm (STBVA), a blockchain-based voting system powered by Proof of Authority (PoA) consensus, elliptic curve cryptography (ECC), and homomorphic encryption. Accordingly, PoA can support deterministic fast block production with low computational overhead, which makes it suitable for regulated election environments. In particular, ECC offers efficient authentication for users, while Paillier homomorphic encryption keeps votes private during tallying processes without revealing individual ballots. The proposed system is implemented and evaluated on a permissioned blockchain network consisting of seven validators and 20 full nodes, accommodating up to 500,000 simulated voters. Experimental results show that confirmation latency is 1.2 s at median, the sustained throughput is 1200 tps, and the accuracy of end-to-end vote recording is 99.8\%. Thereafter, a formal attacker model, security claims, and proof sketches corroborate the resilience against forgery, double voting, and ledger manipulations. The results underpin that STBVA is able to achieve scalable, privacy-preserving, and tamper-resistant election infrastructure to cater for national-level online voting.